source: trunk/kitgen/8.x/blt/generic/bltTreeViewEdit.c@ 182

/*
  Remember row,column where string was acquired.
  postcombobox x y 
        icon?, text, row, column position, fg, bg button?
        based upon style.
  grab set
  SetIcon
  SetText
  SetBg
  SetFg
  SetFont
  SetButton  
 */

/*
 * bltTreeViewEdit.c --
 *
 *      This module implements an hierarchy widget for the BLT toolkit.
 *
 * Copyright 1998-1999 Lucent Technologies, Inc.
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that the above copyright notice appear in all
 * copies and that both that the copyright notice and warranty
 * disclaimer appear in supporting documentation, and that the names
 * of Lucent Technologies or any of their entities not be used in
 * advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.
 *
 * Lucent Technologies disclaims all warranties with regard to this
 * software, including all implied warranties of merchantability and
 * fitness.  In no event shall Lucent Technologies be liable for any
 * special, indirect or consequential damages or any damages
 * whatsoever resulting from loss of use, data or profits, whether in
 * an action of contract, negligence or other tortuous action, arising
 * out of or in connection with the use or performance of this
 * software.
 *
 *      The "treeview" widget was created by George A. Howlett.
 */

#include "bltInt.h"

#ifndef NO_TREEVIEW

#include "bltTreeView.h"
#include <X11/Xutil.h>
#include <X11/Xatom.h>

#define TEXTBOX_FOCUS   (1<<0)
#define TEXTBOX_REDRAW  (1<<1)

static Tcl_IdleProc DisplayTextbox;
static Tcl_FreeProc DestroyTextbox;
static Tcl_TimerProc BlinkCursorProc;
static Tcl_ObjCmdProc TextboxCmd;

/*
 * Textbox --
 *
 *      This structure is shared by entries when their labels are
 *      edited via the keyboard.  It maintains the location of the
 *      insertion cursor and the text selection for the editted entry.
 *      The structure is shared since we need only one.  The "focus"
 *      entry should be the only entry receiving KeyPress/KeyRelease
 *      events at any time.  Information from the previously editted
 *      entry is overwritten.
 *
 *      Note that all the indices internally are in terms of bytes,
 *      not characters.  This is because UTF-8 strings may encode a
 *      single character into a multi-byte sequence.  To find the
 *      respective character position
 *
 *              n = Tcl_NumUtfChars(string, index);
 *
 *      where n is the resulting character number.
 */
typedef struct {

    /*
     * This is a SNAFU in the Tk API.  It assumes that only an official
     * Tk "toplevel" widget will ever become a toplevel window (i.e. a
     * window whose parent is the root window).  Because under Win32,
     * Tk tries to use the widget record associated with the TopLevel
     * as a Tk frame widget, to read its menu name.  What this means
     * is that any widget that's going to be a toplevel, must also look
     * like a frame. Therefore we've copied the frame widget structure
     * fields into the token.
     */

    Tk_Window tkwin;            /* Window that embodies the frame.  NULL
                                 * means that the window has been destroyed
                                 * but the data structures haven't yet been
                                 * cleaned up. */
    Display *display;           /* Display containing widget.  Used, among
                                 * other things, so that resources can be
                                 * freed even after tkwin has gone away. */
    Tcl_Interp *interp;         /* Interpreter associated with widget.  Used
                                 * to delete widget command. */
    Tcl_Command widgetCmd;      /* Token for frame's widget command. */
    char *className;            /* Class name for widget (from configuration
                                 * option).  Malloc-ed. */
    int mask;                   /* Either FRAME or TOPLEVEL;  used to select
                                 * which configuration options are valid for
                                 * widget. */
    char *screenName;           /* Screen on which widget is created.  Non-null
                                 * only for top-levels.  Malloc-ed, may be
                                 * NULL. */
    char *visualName;           /* Textual description of visual for window,
                                 * from -visual option.  Malloc-ed, may be
                                 * NULL. */
    char *colormapName;         /* Textual description of colormap for window,
                                 * from -colormap option.  Malloc-ed, may be
                                 * NULL. */
    char *menuName;             /* Textual description of menu to use for
                                 * menubar. Malloc-ed, may be NULL. */
    Colormap colormap;          /* If not None, identifies a colormap
                                 * allocated for this window, which must be
                                 * freed when the window is deleted. */
    Tk_3DBorder border;         /* Structure used to draw 3-D border and
                                 * background.  NULL means no background
                                 * or border. */
    int borderWidth;            /* Width of 3-D border (if any). */
    int relief;                 /* 3-d effect: TK_RELIEF_RAISED etc. */
    int highlightWidth;         /* Width in pixels of highlight to draw
                                 * around widget when it has the focus.
                                 * 0 means don't draw a highlight. */
    XColor *highlightBgColorPtr;
                                /* Color for drawing traversal highlight
                                 * area when highlight is off. */
    XColor *highlightColorPtr;  /* Color for drawing traversal highlight. */
    int width;                  /* Width to request for window.  <= 0 means
                                 * don't request any size. */
    int height;                 /* Height to request for window.  <= 0 means
                                 * don't request any size. */
    Tk_Cursor cursor;           /* Current cursor for window, or None. */
    char *takeFocus;            /* Value of -takefocus option;  not used in
                                 * the C code, but used by keyboard traversal
                                 * scripts.  Malloc'ed, but may be NULL. */
    int isContainer;            /* 1 means this window is a container, 0 means
                                 * that it isn't. */
    char *useThis;              /* If the window is embedded, this points to
                                 * the name of the window in which it is
                                 * embedded (malloc'ed).  For non-embedded
                                 * windows this is NULL. */
    int flags;                  /* Various flags;  see below for
                                 * definitions. */

    /* Textbox-specific fields */
    TreeView *tvPtr;
    int x, y;                   /* Position of window. */

    int active;                 /* Indicates that the frame is active. */
    int exportSelection;

    int insertPos;              /* Position of the cursor within the
                                 * array of bytes of the entry's label. */

    int cursorX, cursorY;       /* Position of the insertion cursor in the
                                 * textbox window. */
    short int cursorWidth;      /* Size of the insertion cursor symbol. */
    short int cursorHeight;

    int selAnchor;              /* Fixed end of selection. Used to extend
                                 * the selection while maintaining the
                                 * other end of the selection. */
    int selFirst;               /* Position of the first character in the
                                 * selection. */
    int selLast;                /* Position of the last character in the
                                 * selection. */

    int cursorOn;               /* Indicates if the cursor is displayed. */
    int onTime, offTime;        /* Time in milliseconds to wait before
                                 * changing the cursor from off-to-on
                                 * and on-to-off. Setting offTime to 0 makes
                                 * the cursor steady. */
    Tcl_TimerToken timerToken;  /* Handle for a timer event called periodically
                                 * to blink the cursor. */
    /* Data-specific fields. */
    TreeViewEntry *entryPtr;    /* Selected entry */
    TreeViewColumn *columnPtr;  /* Column of entry to be edited */
    TreeViewStyle *stylePtr;
    TreeViewIcon icon;
    int gap;
    char *string;
    TextLayout *textPtr;
    Tk_Font font;
    GC gc;

    Tk_3DBorder selBorder;
    int selRelief;
    int selBorderWidth;
    XColor *selFgColor;         /* Text color of a selected entry. */
    int buttonBorderWidth;
    Tk_3DBorder buttonBorder;
    int buttonRelief;
} Textbox;

#define DEF_TEXTBOX_BACKGROUND          RGB_WHITE
#define DEF_TEXTBOX_BORDERWIDTH STD_BORDERWIDTH
#ifdef WIN32
#define DEF_TEXTBOX_BUTTON_BACKGROUND  RGB_GREY85
#else
#define DEF_TEXTBOX_BUTTON_BACKGROUND  RGB_GREY90
#endif
#define DEF_TEXTBOX_BUTTON_BORDERWIDTH  "2"
#define DEF_TEXTBOX_BUTTON_RELIEF       "raised"
#define DEF_TEXTBOX_CURSOR              (char *)NULL
#define DEF_TEXTBOX_EXPORT_SELECTION    "no"
#define DEF_TEXTBOX_NORMAL_BACKGROUND   STD_NORMAL_BACKGROUND
#define DEF_TEXTBOX_NORMAL_FG_MONO      STD_ACTIVE_FG_MONO
#define DEF_TEXTBOX_RELIEF              "sunken"
#define DEF_TEXTBOX_SELECT_BACKGROUND   RGB_LIGHTBLUE0
#define DEF_TEXTBOX_SELECT_BG_MONO      STD_SELECT_BG_MONO
#define DEF_TEXTBOX_SELECT_BORDERWIDTH "1"
#define DEF_TEXTBOX_SELECT_FOREGROUND   STD_SELECT_FOREGROUND
#define DEF_TEXTBOX_SELECT_FG_MONO      STD_SELECT_FG_MONO
#define DEF_TEXTBOX_SELECT_RELIEF       "flat"

/* Textbox Procedures */
static Blt_ConfigSpec textboxConfigSpecs[] =
{
    {BLT_CONFIG_BORDER, "-background", "background", "Background",
        DEF_TEXTBOX_BACKGROUND, Blt_Offset(Textbox, border), 0},
    {BLT_CONFIG_SYNONYM, "-bd", "borderWidth", (char *)NULL, (char *)NULL, 0,0},
    {BLT_CONFIG_SYNONYM, "-bg", "background", (char *)NULL, (char *)NULL, 0,0},
    {BLT_CONFIG_ACTIVE_CURSOR, "-cursor", "cursor", "Cursor",
        DEF_TEXTBOX_CURSOR, Blt_Offset(Textbox, cursor), 
        BLT_CONFIG_NULL_OK},
    {BLT_CONFIG_DISTANCE, "-borderwidth", "borderWidth", "BorderWidth",
        DEF_TEXTBOX_BORDERWIDTH, Blt_Offset(Textbox, borderWidth),
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_BORDER, "-buttonbackground", "buttonBackground", 
        "ButtonBackground", DEF_TEXTBOX_BUTTON_BACKGROUND,
        Blt_Offset(Textbox, buttonBorder), 0},
    {BLT_CONFIG_RELIEF, "-buttonrelief", "buttonRelief", "ButtonRelief",
        DEF_TEXTBOX_BUTTON_RELIEF, Blt_Offset(Textbox, buttonRelief),
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_DISTANCE, "-buttonborderwidth", "buttonBorderWidth", 
        "ButtonBorderWidth", DEF_TEXTBOX_BUTTON_BORDERWIDTH, 
        Blt_Offset(Textbox, buttonBorderWidth),
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_BOOLEAN, "-exportselection", "exportSelection",
        "ExportSelection", DEF_TEXTBOX_EXPORT_SELECTION, 
        Blt_Offset(Textbox, exportSelection), 
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_RELIEF, "-relief", "relief", "Relief",
        DEF_TEXTBOX_RELIEF, Blt_Offset(Textbox, relief), 0},
    {BLT_CONFIG_BORDER, "-selectbackground", "selectBackground", "Background",
        DEF_TEXTBOX_SELECT_BG_MONO, Blt_Offset(Textbox, selBorder),
        BLT_CONFIG_MONO_ONLY},
    {BLT_CONFIG_BORDER, "-selectbackground", "selectBackground", "Background",
        DEF_TEXTBOX_SELECT_BACKGROUND, Blt_Offset(Textbox, selBorder),
        BLT_CONFIG_COLOR_ONLY},
    {BLT_CONFIG_DISTANCE, "-selectborderwidth", "selectBorderWidth", 
        "BorderWidth", DEF_TEXTBOX_SELECT_BORDERWIDTH, 
        Blt_Offset(Textbox, selBorderWidth), 
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_COLOR, "-selectforeground", "selectForeground", "Foreground",

        DEF_TEXTBOX_SELECT_FG_MONO, Blt_Offset(Textbox, selFgColor),
        BLT_CONFIG_MONO_ONLY},
    {BLT_CONFIG_COLOR, "-selectforeground", "selectForeground", "Foreground",
        DEF_TEXTBOX_SELECT_FOREGROUND, Blt_Offset(Textbox, selFgColor),
        BLT_CONFIG_COLOR_ONLY},
    {BLT_CONFIG_RELIEF, "-selectrelief", "selectRelief", "Relief",
        DEF_TEXTBOX_SELECT_RELIEF, Blt_Offset(Textbox, selRelief),
        BLT_CONFIG_DONT_SET_DEFAULT},
    {BLT_CONFIG_END, (char *)NULL, (char *)NULL, (char *)NULL, (char *)NULL, 
        0, 0}
};

static Tk_LostSelProc TextboxLostSelectionProc;
static Tk_SelectionProc TextboxSelectionProc;
static Tk_EventProc TextboxEventProc;

/*
 *----------------------------------------------------------------------
 *
 * EventuallyRedraw --
 *
 *      Queues a request to redraw the widget at the next idle point.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Information gets redisplayed.  Right now we don't do selective
 *      redisplays:  the whole window will be redrawn.
 *
 *----------------------------------------------------------------------
 */
static void
EventuallyRedraw(tbPtr)
    Textbox *tbPtr;
{
    if ((tbPtr->tkwin != NULL) && 
        ((tbPtr->flags & TEXTBOX_REDRAW) == 0)) {
        tbPtr->flags |= TEXTBOX_REDRAW;
        Tcl_DoWhenIdle(DisplayTextbox, tbPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * BlinkCursorProc --
 *
 *      This procedure is called as a timer handler to blink the
 *      insertion cursor off and on.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The cursor gets turned on or off, redisplay gets invoked,
 *      and this procedure reschedules itself.
 *
 *----------------------------------------------------------------------
 */
static void
BlinkCursorProc(clientData)
    ClientData clientData;      /* Pointer to record describing entry. */
{
    Textbox *tbPtr = clientData;
    int interval;

    if (!(tbPtr->flags & TEXTBOX_FOCUS) || (tbPtr->offTime == 0)) {
        return;
    }
    if (tbPtr->active) {
        tbPtr->cursorOn ^= 1;
        interval = (tbPtr->cursorOn) ? tbPtr->onTime : tbPtr->offTime;
        tbPtr->timerToken = 
            Tcl_CreateTimerHandler(interval, BlinkCursorProc, tbPtr);
        EventuallyRedraw(tbPtr);
    }
}

/*
 * --------------------------------------------------------------
 *
 * TextboxEventProc --
 *
 *      This procedure is invoked by the Tk dispatcher for various
 *      events on treeview widgets.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      When the window gets deleted, internal structures get
 *      cleaned up.  When it gets exposed, it is redisplayed.
 *
 * --------------------------------------------------------------
 */
static void
TextboxEventProc(clientData, eventPtr)
    ClientData clientData;      /* Information about window. */
    XEvent *eventPtr;           /* Information about event. */
{
    Textbox *tbPtr = clientData;

    if (eventPtr->type == Expose) {
        if (eventPtr->xexpose.count == 0) {
            EventuallyRedraw(tbPtr);
        }
    } else if (eventPtr->type == ConfigureNotify) {
        EventuallyRedraw(tbPtr);
    } else if ((eventPtr->type == FocusIn) || (eventPtr->type == FocusOut)) {
        if (eventPtr->xfocus.detail == NotifyInferior) {
            return;
        }
        if (eventPtr->type == FocusIn) {
            tbPtr->flags |= TEXTBOX_FOCUS;
        } else {
            tbPtr->flags &= ~TEXTBOX_FOCUS;
        }
        Tcl_DeleteTimerHandler(tbPtr->timerToken);
        if ((tbPtr->active) && (tbPtr->flags & TEXTBOX_FOCUS)) {
            tbPtr->cursorOn = TRUE;
            if (tbPtr->offTime != 0) {
                tbPtr->timerToken = Tcl_CreateTimerHandler(tbPtr->onTime, 
                   BlinkCursorProc, tbPtr);
            }
        } else {
            tbPtr->cursorOn = FALSE;
            tbPtr->timerToken = (Tcl_TimerToken) NULL;
        }
        EventuallyRedraw(tbPtr);
    } else if (eventPtr->type == DestroyNotify) {
        if (tbPtr->tkwin != NULL) {
            tbPtr->tkwin = NULL;
        }
        if (tbPtr->flags & TEXTBOX_REDRAW) {
            Tcl_CancelIdleCall(DisplayTextbox, tbPtr);
        }
        if (tbPtr->timerToken != NULL) {
            Tcl_DeleteTimerHandler(tbPtr->timerToken);
        }
        tbPtr->tvPtr->comboWin = NULL;
        Tcl_EventuallyFree(tbPtr, DestroyTextbox);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TextboxLostSelectionProc --
 *
 *      This procedure is called back by Tk when the selection is
 *      grabbed away from a Text widget.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The existing selection is unhighlighted, and the window is
 *      marked as not containing a selection.
 *
 *----------------------------------------------------------------------
 */
static void
TextboxLostSelectionProc(clientData)
    ClientData clientData;      /* Information about Text widget. */
{
    Textbox *tbPtr = clientData;

    if ((tbPtr->selFirst >= 0) && (tbPtr->exportSelection)) {
        tbPtr->selFirst = tbPtr->selLast = -1;
        EventuallyRedraw(tbPtr);
    }
}

static int
PointerToIndex(tbPtr, x, y)
    Textbox *tbPtr;
    int x, y;
{
    TextLayout *textPtr;
    Tk_FontMetrics fontMetrics;
    TextFragment *fragPtr;
    int nBytes;
    register int i;
    int total;

    if ((tbPtr->string == NULL) || (tbPtr->string[0] == '\0')) {
        return 0;
    }
    x -= tbPtr->selBorderWidth;
    y -= tbPtr->selBorderWidth;

    textPtr = tbPtr->textPtr;

    /* Bound the y-coordinate within the window. */
    if (y < 0) {
        y = 0;
    } else if (y >= textPtr->height) {
        y = textPtr->height - 1;
    }
    /* 
     * Compute the line that contains the y-coordinate. 
     *
     * FIXME: This assumes that segments are distributed 
     *       line-by-line.  This may change in the future.
     */
    Tk_GetFontMetrics(tbPtr->font, &fontMetrics);
    fragPtr = textPtr->fragArr;
    total = 0;
    for (i = (y / fontMetrics.linespace); i > 0; i--) {
        total += fragPtr->count;
        fragPtr++;
    }
    if (x < 0) {
        nBytes = 0;
    } else if (x >= textPtr->width) {
        nBytes = fragPtr->count;
    } else {
        int newX;

        /* Find the character underneath the pointer. */
        nBytes = Tk_MeasureChars(tbPtr->font, fragPtr->text, fragPtr->count, 
                 x, 0, &newX);
        if ((newX < x) && (nBytes < fragPtr->count)) {
            double fract;
            int length, charSize;
            char *next;

            next = fragPtr->text + nBytes;
#if HAVE_UTF
            {
                Tcl_UniChar dummy;

                length = Tcl_UtfToUniChar(next, &dummy);
            }
#else
            length = 1;
#endif
            charSize = Tk_TextWidth(tbPtr->font, next, length);
            fract = ((double)(x - newX) / (double)charSize);
            if (ROUND(fract)) {
                nBytes += length;
            }
        }
    }
    return nBytes + total;
}

static int
IndexToPointer(tbPtr)
    Textbox *tbPtr;
{
    int x, y;
    int maxLines;
    TextLayout *textPtr;
    Tk_FontMetrics fontMetrics;
    int nBytes;
    int sum;
    TextFragment *fragPtr;
    register int i;

    textPtr = tbPtr->textPtr;
    Tk_GetFontMetrics(tbPtr->font, &fontMetrics);
    maxLines = (textPtr->height / fontMetrics.linespace) - 1;

    sum = 0;
    x = y = tbPtr->borderWidth;
    if (tbPtr->icon != NULL) {
        x += TreeViewIconWidth(tbPtr->icon) + 2 * tbPtr->gap;
    }
    fragPtr = textPtr->fragArr;
    for (i = 0; i <= maxLines; i++) {
        /* Total the number of bytes on each line.  Include newlines. */
        nBytes = fragPtr->count + 1;
        if ((sum + nBytes) > tbPtr->insertPos) {
            x += Tk_TextWidth(tbPtr->font, fragPtr->text, 
                tbPtr->insertPos - sum);
            break;
        }
        y += fontMetrics.linespace;
        sum += nBytes;
        fragPtr++;
    }
    tbPtr->cursorX = x;
    tbPtr->cursorY = y;
    tbPtr->cursorHeight = fontMetrics.linespace;
    tbPtr->cursorWidth = 3;
    return TCL_OK;
}

static void
UpdateLayout(tbPtr)
    Textbox *tbPtr;
{
    TextStyle ts;
    int width, height;
    TextLayout *textPtr;
    int gap;
    int iconWidth, iconHeight;

    gap = iconWidth = iconHeight = 0;
    if (tbPtr->icon != NULL) {
        iconWidth = TreeViewIconWidth(tbPtr->icon) + 4;
        iconHeight = TreeViewIconHeight(tbPtr->icon);
        gap = tbPtr->gap;
    }

    /* The layout is based upon the current font. */
    Blt_InitTextStyle(&ts);
    ts.anchor = TK_ANCHOR_NW;
    ts.justify = TK_JUSTIFY_LEFT;
    ts.font = tbPtr->font;
    textPtr = Blt_GetTextLayout(tbPtr->string, &ts);
    if (tbPtr->textPtr != NULL) {
        Blt_Free(tbPtr->textPtr);
    }
    tbPtr->textPtr = textPtr;

    width = iconWidth + textPtr->width + gap * 2;
    height = MAX(iconHeight, textPtr->height);

    if (width <= tbPtr->columnPtr->width) {
        width = tbPtr->columnPtr->width;
    }
    if (height < tbPtr->entryPtr->height) {
        height = tbPtr->entryPtr->height;
    }
    tbPtr->width = width + (2 * tbPtr->borderWidth);
    tbPtr->height = height + (2 * tbPtr->borderWidth);
    IndexToPointer(tbPtr);
    Tk_MoveResizeWindow(tbPtr->tkwin, tbPtr->x, tbPtr->y, 
              tbPtr->width, tbPtr->height);
    Tk_MapWindow(tbPtr->tkwin);
    XRaiseWindow(tbPtr->display, Tk_WindowId(tbPtr->tkwin));
}

static void
InsertText(tbPtr, insertText, insertPos, nBytes)
    Textbox *tbPtr;
    char *insertText;
    int insertPos;
    int nBytes;
{
    int oldSize, newSize;
    char *oldText, *newText;

    oldText = tbPtr->string;
    oldSize = strlen(oldText);
    newSize = oldSize + nBytes;
    newText = Blt_Malloc(sizeof(char) * (newSize + 1));
    if (insertPos == oldSize) { /* Append */
        strcpy(newText, oldText);
        strcat(newText, insertText);
    } else if (insertPos == 0) {/* Prepend */
        strcpy(newText, insertText);
        strcat(newText, oldText);
    } else {                    /* Insert into existing. */
        char *p;
        
        p = newText;
        strncpy(p, oldText, insertPos);
        p += insertPos;
        strcpy(p, insertText);
        p += nBytes;
        strcpy(p, oldText + insertPos);
    }

    /* 
     * All indices from the start of the insertion to the end of the
     * string need to be updated.  Simply move the indices down by the
     * number of characters added.  
     */
    if (tbPtr->selFirst >= insertPos) {
        tbPtr->selFirst += nBytes;
    }
    if (tbPtr->selLast > insertPos) {
        tbPtr->selLast += nBytes;
    }
    if ((tbPtr->selAnchor > insertPos) || (tbPtr->selFirst >= insertPos)) {
        tbPtr->selAnchor += nBytes;
    }
    if (tbPtr->string != NULL) {
        Blt_Free(tbPtr->string);
    }
    tbPtr->string = newText;
    tbPtr->insertPos = insertPos + nBytes;
    UpdateLayout(tbPtr);
}

static int
DeleteText(tbPtr, firstPos, lastPos)
    Textbox *tbPtr;
    int firstPos, lastPos;
{
    char *oldText, *newText;
    int oldSize, newSize;
    int nBytes;
    char *p;

    oldText = tbPtr->string;
    if (firstPos > lastPos) {
        return TCL_OK;
    }
    lastPos++;                  /* Now is the position after the last
                                 * character. */

    nBytes = lastPos - firstPos;

    oldSize = strlen(oldText) + 1;
    newSize = oldSize - nBytes + 1;
    newText = Blt_Malloc(sizeof(char) * newSize);
    p = newText;
    if (firstPos > 0) {
        strncpy(p, oldText, firstPos);
        p += firstPos;
    }
    *p = '\0';
    if (lastPos < oldSize) {
        strcpy(p, oldText + lastPos);
    }
    Blt_Free(oldText);

    /*
     * Since deleting characters compacts the character array, we need to
     * update the various character indices according.  It depends where
     * the index occurs in relation to range of deleted characters:
     *
     *   before         Ignore.
     *   within         Move the index back to the start of the deletion.
     *   after          Subtract off the deleted number of characters,
     *                  since the array has been compressed by that
     *                  many characters.
     *
     */
    if (tbPtr->selFirst >= firstPos) {
        if (tbPtr->selFirst >= lastPos) {
            tbPtr->selFirst -= nBytes;
        } else {
            tbPtr->selFirst = firstPos;
        }
    }
    if (tbPtr->selLast >= firstPos) {
        if (tbPtr->selLast >= lastPos) {
            tbPtr->selLast -= nBytes;
        } else {
            tbPtr->selLast = firstPos;
        }
    }
    if (tbPtr->selLast <= tbPtr->selFirst) {
        tbPtr->selFirst = tbPtr->selLast = -1; /* Cut away the entire
                                                    * selection. */ 
    }
    if (tbPtr->selAnchor >= firstPos) {
        if (tbPtr->selAnchor >= lastPos) {
            tbPtr->selAnchor -= nBytes;
        } else {
            tbPtr->selAnchor = firstPos;
        }
    }
    if (tbPtr->insertPos >= firstPos) {
        if (tbPtr->insertPos >= lastPos) {
            tbPtr->insertPos -= nBytes;
        } else {
            tbPtr->insertPos = firstPos;
        }
    }
    tbPtr->string = newText;
    UpdateLayout(tbPtr);
    EventuallyRedraw(tbPtr);
    return TCL_OK;
}

static int
AcquireText(tvPtr, tbPtr, entryPtr, columnPtr)
    TreeView *tvPtr;
    Textbox *tbPtr;
    TreeViewEntry *entryPtr;
    TreeViewColumn *columnPtr;
{
    TreeViewStyle *stylePtr;
    int x, y;
    char *string;
    TreeViewIcon icon;

    if (columnPtr == &tvPtr->treeColumn) {
        int level;

        level = DEPTH(tvPtr, entryPtr->node);
        x = SCREENX(tvPtr, entryPtr->worldX);
        y = SCREENY(tvPtr, entryPtr->worldY);
        x += ICONWIDTH(level) + ICONWIDTH(level + 1) + 4;
        string = GETLABEL(entryPtr);
        stylePtr = columnPtr->stylePtr;
        icon = Blt_TreeViewGetEntryIcon(tvPtr, entryPtr);
    } else {
        TreeViewValue *valuePtr;

        x = SCREENX(tvPtr, columnPtr->worldX);
        y = SCREENY(tvPtr, entryPtr->worldY);
        stylePtr = columnPtr->stylePtr;
        valuePtr = Blt_TreeViewFindValue(entryPtr, columnPtr);
        string = valuePtr->string;
        if (valuePtr->stylePtr != NULL) {
            stylePtr = valuePtr->stylePtr;
        }
        icon = stylePtr->icon;
    }
    if (tbPtr->textPtr != NULL) {
        Blt_Free(tbPtr->textPtr);
        tbPtr->textPtr = NULL;
    }
    if (tbPtr->string != NULL) {
        Blt_Free(tbPtr->string);
    }
    if (string == NULL) {
        string = "";
    }
    tbPtr->icon = icon;
    tbPtr->entryPtr = entryPtr;
    tbPtr->columnPtr = columnPtr;
    tbPtr->x = x - tbPtr->borderWidth;
    tbPtr->y = y - tbPtr->borderWidth;
    
    tbPtr->gap = stylePtr->gap;
    tbPtr->string = Blt_Strdup(string);
    tbPtr->gc = Blt_TreeViewGetStyleGC(stylePtr);
    tbPtr->font = Blt_TreeViewGetStyleFont(tvPtr, stylePtr);
    tbPtr->selFirst = tbPtr->selLast = -1;
    UpdateLayout(tbPtr);
    Tk_MapWindow(tbPtr->tkwin);
    EventuallyRedraw(tbPtr);
    return TCL_OK;
}


/*
 *---------------------------------------------------------------------------
 *
 * GetIndexFromObj --
 *
 *      Parse an index into an entry and return either its value
 *      or an error.
 *
 * Results:
 *      A standard Tcl result.  If all went well, then *indexPtr is
 *      filled in with the character index (into entryPtr) corresponding to
 *      string.  The index value is guaranteed to lie between 0 and
 *      the number of characters in the string, inclusive.  If an
 *      error occurs then an error message is left in the interp's result.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
static int
GetIndexFromObj(interp, tbPtr, objPtr, indexPtr)
    Tcl_Interp *interp;
    Textbox *tbPtr;
    Tcl_Obj *objPtr;
    int *indexPtr;
{
    int textPos;
    char c;
    char *string;

    string = Tcl_GetString(objPtr);
    if ((tbPtr->string == NULL) || (tbPtr->string[0] == '\0')) {
        *indexPtr = 0;
        return TCL_OK;
    }
    c = string[0];
    if ((c == 'a') && (strcmp(string, "anchor") == 0)) {
        textPos = tbPtr->selAnchor;
    } else if ((c == 'e') && (strcmp(string, "end") == 0)) {
        textPos = strlen(tbPtr->string);
    } else if ((c == 'i') && (strcmp(string, "insert") == 0)) {
        textPos = tbPtr->insertPos;
    } else if ((c == 'n') && (strcmp(string, "next") == 0)) {
        textPos = tbPtr->insertPos;
        if (textPos < (int)strlen(tbPtr->string)) {
            textPos++;
        }
    } else if ((c == 'l') && (strcmp(string, "last") == 0)) {
        textPos = tbPtr->insertPos;
        if (textPos > 0) {
            textPos--;
        }
    } else if ((c == 's') && (strcmp(string, "sel.first") == 0)) {
        if (tbPtr->selFirst < 0) {
            textPos = -1;
        } else {
            textPos = tbPtr->selFirst;
        }
    } else if ((c == 's') && (strcmp(string, "sel.last") == 0)) {
        if (tbPtr->selLast < 0) {
            textPos = -1;
        } else {
            textPos = tbPtr->selLast;
        }
    } else if (c == '@') {
        int x, y;

        if (Blt_GetXY(interp, tbPtr->tkwin, string, &x, &y) != TCL_OK) {
            return TCL_ERROR;
        }
        textPos = PointerToIndex(tbPtr, x, y);
    } else if (isdigit((int)c)) {
        int number;
        int maxChars;

        if (Tcl_GetIntFromObj(interp, objPtr, &number) != TCL_OK) {
            return TCL_ERROR;
        }
        /* Don't allow the index to point outside the label. */
        maxChars = Tcl_NumUtfChars(tbPtr->string, -1);
        if (number < 0) {
            textPos = 0;
        } else if (number > maxChars) {
            textPos = strlen(tbPtr->string);
        } else {
            textPos = Tcl_UtfAtIndex(tbPtr->string, number) - 
                tbPtr->string;
        }
    } else {
        if (interp != NULL) {
            Tcl_AppendResult(interp, "bad label index \"", string, "\"",
                             (char *)NULL);
        }
        return TCL_ERROR;
    }
    *indexPtr = textPos;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * SelectText --
 *
 *      Modify the selection by moving its un-anchored end.  This
 *      could make the selection either larger or smaller.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The selection changes.
 *
 *----------------------------------------------------------------------
 */
static int
SelectText(tbPtr, textPos)
    Textbox *tbPtr;     /* Information about textbox. */
    int textPos;                /* Index of element that is to
                                 * become the "other" end of the
                                 * selection. */
{
    int selFirst, selLast;

    /*
     * Grab the selection if we don't own it already.
     */
    if ((tbPtr->exportSelection) && (tbPtr->selFirst == -1)) {
        Tk_OwnSelection(tbPtr->tkwin, XA_PRIMARY, 
                        TextboxLostSelectionProc, tbPtr);
    }
    /*  If the anchor hasn't been set yet, assume the beginning of the text*/
    if (tbPtr->selAnchor < 0) {
        tbPtr->selAnchor = 0;
    }
    if (tbPtr->selAnchor <= textPos) {
        selFirst = tbPtr->selAnchor;
        selLast = textPos;
    } else {
        selFirst = textPos;
        selLast = tbPtr->selAnchor;
    }
    if ((tbPtr->selFirst != selFirst) || (tbPtr->selLast != selLast)) {
        tbPtr->selFirst = selFirst;
        tbPtr->selLast = selLast;
        EventuallyRedraw(tbPtr);
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * TextboxSelectionProc --
 *
 *      This procedure is called back by Tk when the selection is
 *      requested by someone.  It returns part or all of the selection
 *      in a buffer provided by the caller.
 *
 * Results:
 *      The return value is the number of non-NULL bytes stored at
 *      buffer.  Buffer is filled (or partially filled) with a
 *      NUL-terminated string containing part or all of the
 *      selection, as given by offset and maxBytes.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
static int
TextboxSelectionProc(clientData, offset, buffer, maxBytes)
    ClientData clientData;      /* Information about the widget. */
    int offset;                 /* Offset within selection of first
                                 * character to be returned. */
    char *buffer;               /* Location in which to place
                                 * selection. */
    int maxBytes;               /* Maximum number of bytes to place
                                 * at buffer, not including terminating
                                 * NULL character. */
{
    Textbox *tbPtr = clientData;
    int size;

    size = strlen(tbPtr->string + offset);
    /*
     * Return the string currently in the textbox.
     */
    strncpy(buffer, tbPtr->string + offset, maxBytes);
    buffer[maxBytes] = '\0';
    return (size > maxBytes) ? maxBytes : size;
}


static void
DestroyTextbox(data)
    DestroyData data;
{
    Textbox *tbPtr = (Textbox *)data;

    Blt_FreeObjOptions(textboxConfigSpecs, (char *)tbPtr, 
        tbPtr->display, 0);

    if (tbPtr->string != NULL) {
        Blt_Free(tbPtr->string);
    }
    if (tbPtr->textPtr != NULL) {
        Blt_Free(tbPtr->textPtr);
    }
    if (tbPtr->timerToken != NULL) {
        Tcl_DeleteTimerHandler(tbPtr->timerToken);
    }
    if (tbPtr->tkwin != NULL) {
        Tk_DeleteSelHandler(tbPtr->tkwin, XA_PRIMARY, XA_STRING);
    }
    Blt_Free(tbPtr);
}

static void
ConfigureTextbox(tbPtr)
    Textbox *tbPtr;
{
#ifdef notdef
    GC newGC;
    Textbox *tbPtr = tvPtr->tbPtr;
    XGCValues gcValues;
    unsigned long gcMask;

    /*
     * GC for edit window.
     */
    gcMask = 0;
    newGC = Tk_GetGC(tbPtr->tkwin, gcMask, &gcValues);
    if (tbPtr->gc != NULL) {
        Tk_FreeGC(tbPtr->display, tbPtr->gc);
    }
    tbPtr->gc = newGC;
    tbPtr->width = tbPtr->textPtr->width + 
        2 * (tbPtr->borderWidth + tbPtr->highlightWidth);
    tbPtr->height = tbPtr->textPtr->height + 
        2 * (tbPtr->borderWidth + tbPtr->highlightWidth);
    
    if (Tk_IsMapped(tbPtr->tkwin)) {
        if ((tbPtr->height != Tk_Height(tbPtr->tkwin)) ||
            (tbPtr->width != Tk_Width(tbPtr->tkwin))) {
            Tk_ResizeWindow(tbPtr->tkwin, tbPtr->width, tbPtr->height);
        }
    }
#endif
}

int
Blt_TreeViewTextbox(tvPtr, entryPtr, columnPtr)
    TreeView *tvPtr;
    TreeViewEntry *entryPtr;
    TreeViewColumn *columnPtr;
{
    Tk_Window tkwin;
    Textbox *tbPtr;
    char editClass[20];

    if (tvPtr->comboWin != NULL) {
        Tk_DestroyWindow(tvPtr->comboWin);
    }
    tkwin = Tk_CreateWindow(tvPtr->interp, tvPtr->tkwin, "edit", (char *)NULL);
    if (tkwin == NULL) {
        return TCL_ERROR;
    }

    Tk_MakeWindowExist(tkwin);

    sprintf(editClass, "%sEditor", Tk_Class(tvPtr->tkwin));
    Tk_SetClass(tkwin, editClass); 

    tbPtr = Blt_Calloc(1, sizeof(Textbox));
    assert(tbPtr);

    tbPtr->interp = tvPtr->interp;
    tbPtr->display = Tk_Display(tkwin);
    tbPtr->tkwin = tkwin;
    tbPtr->borderWidth = 1;
    tbPtr->relief = TK_RELIEF_SOLID;
    tbPtr->selRelief = TK_RELIEF_FLAT;
    tbPtr->selBorderWidth = 1;
    tbPtr->selAnchor = -1;
    tbPtr->selFirst = tbPtr->selLast = -1;
    tbPtr->onTime = 600;
    tbPtr->active = TRUE;
    tbPtr->offTime = 300;
    tbPtr->tvPtr = tvPtr;
    tbPtr->buttonRelief = TK_RELIEF_SUNKEN;
    tbPtr->buttonBorderWidth = 1;
    tvPtr->comboWin = tkwin;
#if (TK_MAJOR_VERSION > 4)
    Blt_SetWindowInstanceData(tkwin, tbPtr);
#endif
    Tk_CreateSelHandler(tkwin, XA_PRIMARY, XA_STRING, 
        TextboxSelectionProc, tbPtr, XA_STRING);
    Tk_CreateEventHandler(tkwin, ExposureMask | StructureNotifyMask |
        FocusChangeMask, TextboxEventProc, tbPtr);
    Tcl_CreateObjCommand(tvPtr->interp, Tk_PathName(tkwin), 
        TextboxCmd, tbPtr, NULL);
    if (Blt_ConfigureWidgetFromObj(tvPtr->interp, tkwin, textboxConfigSpecs, 0, 
        (Tcl_Obj **)NULL, (char *)tbPtr, 0) != TCL_OK) {
        Tk_DestroyWindow(tkwin);
        return TCL_ERROR;
    }
    AcquireText(tvPtr, tbPtr, entryPtr, columnPtr);
    tbPtr->insertPos = strlen(tbPtr->string);
    
    Tk_MoveResizeWindow(tkwin, tbPtr->x, tbPtr->y, tbPtr->width, 
        tbPtr->height);
    Tk_MapWindow(tkwin);
    Tk_MakeWindowExist(tkwin);
    XRaiseWindow(tbPtr->display, Tk_WindowId(tkwin));
    EventuallyRedraw(tbPtr);
    return TCL_OK;
}

static void
DisplayTextbox(clientData)
    ClientData clientData;
{
    Textbox *tbPtr = clientData;
    Pixmap drawable;
    register int i;
    int x1, x2;
    int count, nChars;
    int leftPos, rightPos;
    int selStart, selEnd, selLength;
    int x, y;
    TextFragment *fragPtr;
    Tk_FontMetrics fontMetrics;
#ifdef notdef
    int buttonX, buttonY, buttonWidth, buttonHeight;
#endif
    tbPtr->flags &= ~TEXTBOX_REDRAW;
    if (!Tk_IsMapped(tbPtr->tkwin)) {
        return;
    }
    if (tbPtr->columnPtr == NULL) {
        return;
    }
    drawable = Tk_GetPixmap(tbPtr->display, Tk_WindowId(tbPtr->tkwin), 
        Tk_Width(tbPtr->tkwin), Tk_Height(tbPtr->tkwin), 
        Tk_Depth(tbPtr->tkwin));

    Blt_Fill3DRectangle(tbPtr->tkwin, drawable, tbPtr->border, 0, 0,
        Tk_Width(tbPtr->tkwin), Tk_Height(tbPtr->tkwin), 
        tbPtr->borderWidth, tbPtr->relief);

    x = tbPtr->borderWidth + tbPtr->gap;
    y = tbPtr->borderWidth;

#ifdef notdef
    buttonX = Tk_Width(tbPtr->tkwin) - 
        (tbPtr->borderWidth + tbPtr->gap + 1);
    buttonY = tbPtr->borderWidth + 1;
#endif

    if (tbPtr->icon != NULL) {
        y += (tbPtr->height - TreeViewIconHeight(tbPtr->icon)) / 2;
        Tk_RedrawImage(TreeViewIconBits(tbPtr->icon), 0, 0, 
                       TreeViewIconWidth(tbPtr->icon), 
                       TreeViewIconHeight(tbPtr->icon), 
                       drawable, x, y);
        x += TreeViewIconWidth(tbPtr->icon) + tbPtr->gap;
    }
    
    Tk_GetFontMetrics(tbPtr->font, &fontMetrics);
    fragPtr = tbPtr->textPtr->fragArr;
    count = 0;
    y = tbPtr->borderWidth;
    if (tbPtr->height > fontMetrics.linespace) {
        y += (tbPtr->height - fontMetrics.linespace) / 2;
    }
    for (i = 0; i < tbPtr->textPtr->nFrags; i++, fragPtr++) {
        leftPos = count;
        count += fragPtr->count;
        rightPos = count;
        if ((rightPos < tbPtr->selFirst) || (leftPos > tbPtr->selLast)) {
            /* No part of the text fragment is selected. */
            Tk_DrawChars(tbPtr->display, drawable, tbPtr->gc, 
                         tbPtr->font, fragPtr->text, fragPtr->count, 
                         x + fragPtr->x, y + fragPtr->y);
            continue;
        }

        /*
         *  A text fragment can have up to 3 regions:
         *
         *      1. Text before the start the selection
         *      2. Selected text itself (drawn in a raised border)
         *      3. Text following the selection.
         */

        selStart = leftPos;
        selEnd = rightPos;
        /* First adjust selected region for current line. */
        if (tbPtr->selFirst > leftPos) {
            selStart = tbPtr->selFirst;
        }
        if (tbPtr->selLast < rightPos) {
            selEnd = tbPtr->selLast;
        }
        selLength = (selEnd - selStart);
        x1 = x;

        if (selStart > leftPos) { /* Normal text preceding the selection */
            nChars = (selStart - leftPos);
            Tk_MeasureChars(tbPtr->font, tbPtr->string + leftPos,
                    nChars, 10000, DEF_TEXT_FLAGS, &x1);
            x1 += x;
        }
        if (selLength > 0) {    /* The selection itself */
            int width;

            Tk_MeasureChars(tbPtr->font, fragPtr->text + selStart, selLength,
                10000, DEF_TEXT_FLAGS, &x2);
            x2 += x;
            width = (x2 - x1) + 1;
            Blt_Fill3DRectangle(tbPtr->tkwin, drawable, tbPtr->selBorder,
                x1, y + fragPtr->y - fontMetrics.ascent, 
                width, fontMetrics.linespace,
                tbPtr->selBorderWidth, tbPtr->selRelief);
        }
        Tk_DrawChars(Tk_Display(tbPtr->tkwin), drawable, tbPtr->gc, 
             tbPtr->font, fragPtr->text, fragPtr->count, 
             fragPtr->x + x, fragPtr->y + y);
    }
    if ((tbPtr->flags & TEXTBOX_FOCUS) && (tbPtr->cursorOn)) {
        int left, top, right, bottom;

        IndexToPointer(tbPtr);
        left = tbPtr->cursorX + 1;
        right = left + 1;
        top = tbPtr->cursorY;
        if (tbPtr->height > fontMetrics.linespace) {
            top += (tbPtr->height - fontMetrics.linespace) / 2;
        }
        bottom = top + tbPtr->cursorHeight - 1;
        XDrawLine(tbPtr->display, drawable, tbPtr->gc, left, top, left,
                bottom);
        XDrawLine(tbPtr->display, drawable, tbPtr->gc, left - 1, top, right,
                top);
        XDrawLine(tbPtr->display, drawable, tbPtr->gc, left - 1, bottom, 
                right, bottom);
    }
#ifdef notdef
    buttonWidth = STD_ARROW_WIDTH + 6 + 2 * tbPtr->buttonBorderWidth;
    buttonX -= buttonWidth;
    buttonHeight = Tk_Height(tbPtr->tkwin) - 4;
    Blt_Fill3DRectangle(tbPtr->tkwin, drawable, tbPtr->buttonBorder, 
               buttonX, buttonY, buttonWidth, buttonHeight,
               tbPtr->buttonBorderWidth, tbPtr->buttonRelief); 
    
    buttonX += buttonWidth / 2;
    buttonY = tbPtr->height / 2;
    Blt_DrawArrow(tbPtr->display, drawable, tbPtr->gc, buttonX,
                  buttonY, STD_ARROW_HEIGHT, ARROW_DOWN);
#endif
    Blt_Draw3DRectangle(tbPtr->tkwin, drawable, tbPtr->border, 0, 0,
        Tk_Width(tbPtr->tkwin), Tk_Height(tbPtr->tkwin), 
        tbPtr->borderWidth, tbPtr->relief);
    XCopyArea(tbPtr->display, drawable, Tk_WindowId(tbPtr->tkwin),
        tbPtr->gc, 0, 0, Tk_Width(tbPtr->tkwin), 
        Tk_Height(tbPtr->tkwin), 0, 0);
    Tk_FreePixmap(tbPtr->display, drawable);
}

/*ARGSUSED*/
static int
ApplyOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;       /* Not used. */
{
    TreeViewEntry *entryPtr;
    TreeView *tvPtr = tbPtr->tvPtr;

    entryPtr = tbPtr->entryPtr;
    if (tbPtr->columnPtr == &tvPtr->treeColumn) {
        if (entryPtr->labelUid != NULL) {
            Blt_TreeViewFreeUid(tvPtr, entryPtr->labelUid);
        }
        if (tbPtr->string == NULL) {
            entryPtr->labelUid = Blt_TreeViewGetUid(tvPtr, "");
        } else {
            entryPtr->labelUid = Blt_TreeViewGetUid(tvPtr, tbPtr->string);
        }
    } else {
        TreeViewColumn *columnPtr;
        Tcl_Obj *objPtr;

        columnPtr = tbPtr->columnPtr;
        objPtr = Tcl_NewStringObj(tbPtr->string, -1);
        if (Blt_TreeSetValueByKey(interp, tvPtr->tree, entryPtr->node, 
                columnPtr->key, objPtr) != TCL_OK) {
            Tcl_DecrRefCount(objPtr);
            return TCL_ERROR;
        }
        entryPtr->flags |= ENTRY_DIRTY;
    }   
    if (tvPtr != NULL) {
        Blt_TreeViewConfigureEntry(tvPtr, entryPtr, 0, NULL, 
                BLT_CONFIG_OBJV_ONLY);
        tvPtr->flags |= (TV_LAYOUT | TV_DIRTY | TV_RESORT);
        Blt_TreeViewEventuallyRedraw(tvPtr);
    }
    Tk_DestroyWindow(tbPtr->tkwin);
    return TCL_OK;
}

/*ARGSUSED*/
static int
CancelOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;       /* Not used. */
{
    Tk_DestroyWindow(tbPtr->tkwin);
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * CgetOp --
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
static int
CgetOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;
{
    return Blt_ConfigureValueFromObj(interp, tbPtr->tkwin, 
        textboxConfigSpecs, (char *)tbPtr, objv[2], 0);
}

/*
 *----------------------------------------------------------------------
 *
 * ConfigureOp --
 *
 *      This procedure is called to process a list of configuration
 *      options database, in order to reconfigure the one of more
 *      entries in the widget.
 *
 *        .c configure option value
 *
 * Results:
 *      A standard Tcl result.  If TCL_ERROR is returned, then
 *      interp->result contains an error message.
 *
 * Side effects:
 *      Configuration information, such as text string, colors, font,
 *      etc. get set for tvPtr; old resources get freed, if there
 *      were any.  The hypertext is redisplayed.
 *
 *----------------------------------------------------------------------
 */
static int
ConfigureOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;
    int objc;
    Tcl_Obj *CONST *objv;
{
    if (objc == 2) {
        return Blt_ConfigureInfoFromObj(interp, tbPtr->tkwin, 
                textboxConfigSpecs, (char *)tbPtr, (Tcl_Obj *)NULL, 0);
    } else if (objc == 3) {
        return Blt_ConfigureInfoFromObj(interp, tbPtr->tkwin, 
                textboxConfigSpecs, (char *)tbPtr, objv[3], 0);
    }
    if (Blt_ConfigureWidgetFromObj(interp, tbPtr->tkwin, 
        textboxConfigSpecs, objc - 2, objv + 2, (char *)tbPtr, 
        BLT_CONFIG_OBJV_ONLY) != TCL_OK) {
        return TCL_ERROR;
    }
    ConfigureTextbox(tbPtr);
    EventuallyRedraw(tbPtr);
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * DeleteOp --
 *
 *      Remove one or more characters from the label of an entry.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Memory gets freed, the entry gets modified and (eventually)
 *      redisplayed.
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
static int
DeleteOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int firstPos, lastPos;

    if (tbPtr->entryPtr == NULL) {
        return TCL_OK;
    }
    if (GetIndexFromObj(interp, tbPtr, objv[2], &firstPos) != TCL_OK) {
        return TCL_ERROR;
    }
    lastPos = firstPos;
    if ((objc == 4) && 
        (GetIndexFromObj(interp, tbPtr, objv[3], &lastPos) != TCL_OK)) {
        return TCL_ERROR;
    }
    if (firstPos > lastPos) {
        return TCL_OK;
    }
    return DeleteText(tbPtr, firstPos, lastPos);
}


/*
 *----------------------------------------------------------------------
 *
 * IcursorOp --
 *
 *      Returns the numeric index of the given string. Indices can be
 *      one of the following:
 *
 *      "anchor"        Selection anchor.
 *      "end"           End of the label.
 *      "insert"        Insertion cursor.
 *      "sel.first"     First character selected.
 *      "sel.last"      Last character selected.
 *      @x,y            Index at X-Y screen coordinate.
 *      number          Returns the same number.
 *
 * Results:
 *      A standard Tcl result.  If the argument does not represent a
 *      valid label index, then TCL_ERROR is returned and the interpreter
 *      result will contain an error message.
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
static int
IcursorOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;
{
    int textPos;

    if (GetIndexFromObj(interp, tbPtr, objv[2], &textPos) != TCL_OK) {
        return TCL_ERROR;
    }
    if (tbPtr->columnPtr != NULL) {
        tbPtr->insertPos = textPos;
        IndexToPointer(tbPtr);
        EventuallyRedraw(tbPtr);
    }
    return TCL_OK;
}


/*
 *----------------------------------------------------------------------
 *
 * IndexOp --
 *
 *      Returns the numeric index of the given string. Indices can be
 *      one of the following:
 *
 *      "anchor"        Selection anchor.
 *      "end"           End of the label.
 *      "insert"        Insertion cursor.
 *      "sel.first"     First character selected.
 *      "sel.last"      Last character selected.
 *      @x,y            Index at X-Y screen coordinate.
 *      number          Returns the same number.
 *
 * Results:
 *      A standard Tcl result.  If the argument does not represent a
 *      valid label index, then TCL_ERROR is returned and the interpreter
 *      result will contain an error message.
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
static int
IndexOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;
{
    int textPos;

    if (GetIndexFromObj(interp, tbPtr, objv[2], &textPos) != TCL_OK) {
        return TCL_ERROR;
    }
    if ((tbPtr->columnPtr != NULL) && (tbPtr->string != NULL)) {
        int nChars;

        nChars = Tcl_NumUtfChars(tbPtr->string, textPos);
        Tcl_SetObjResult(interp, Tcl_NewIntObj(nChars));
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * InsertOp --
 *
 *      Add new characters to the label of an entry.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      New information gets added to tbPtr;  it will be redisplayed
 *      soon, but not necessarily immediately.
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
static int
InsertOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int extra;
    int insertPos;
    char *string;

    if (tbPtr->entryPtr == NULL) {
        return TCL_ERROR;
    }
    if (GetIndexFromObj(interp, tbPtr, objv[2], &insertPos) != TCL_OK) {
        return TCL_ERROR;
    }
    string = Tcl_GetStringFromObj(objv[3], &extra);
    if (extra == 0) {   /* Nothing to insert. Move the cursor anyways. */
        tbPtr->insertPos = insertPos;
    } else {
        InsertText(tbPtr, string, insertPos, extra);
    }
    return TCL_OK;
}

/*ARGSUSED*/
static int
SelectionAdjustOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int textPos;
    int half1, half2;

    if (GetIndexFromObj(interp, tbPtr, objv[3], &textPos) != TCL_OK) {
        return TCL_ERROR;
    }
    half1 = (tbPtr->selFirst + tbPtr->selLast) / 2;
    half2 = (tbPtr->selFirst + tbPtr->selLast + 1) / 2;
    if (textPos < half1) {
        tbPtr->selAnchor = tbPtr->selLast;
    } else if (textPos > half2) {
        tbPtr->selAnchor = tbPtr->selFirst;
    }
    return SelectText(tbPtr, textPos);
}

/*ARGSUSED*/
static int
SelectionClearOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;       /* Not used. */
{
    if (tbPtr->selFirst != -1) {
        tbPtr->selFirst = tbPtr->selLast = -1;
        EventuallyRedraw(tbPtr);
    }
    return TCL_OK;
}

/*ARGSUSED*/
static int
SelectionFromOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int textPos;

    if (GetIndexFromObj(interp, tbPtr, objv[3], &textPos) != TCL_OK) {
        return TCL_ERROR;
    }
    tbPtr->selAnchor = textPos;
    return TCL_OK;
}

/*ARGSUSED*/
static int
SelectionPresentOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         
    int objc;                   /* Not used. */
    Tcl_Obj *CONST *objv;       /* Not used. */
{
    int bool;

    bool = (tbPtr->selFirst != -1);
    Tcl_SetObjResult(interp, Tcl_NewBooleanObj(bool));
    return TCL_OK;
}

/*ARGSUSED*/
static int
SelectionRangeOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int selFirst, selLast;

    if (GetIndexFromObj(interp, tbPtr, objv[3], &selFirst) != TCL_OK) {
        return TCL_ERROR;
    }
    if (GetIndexFromObj(interp, tbPtr, objv[4], &selLast) != TCL_OK) {
        return TCL_ERROR;
    }
    tbPtr->selAnchor = selFirst;
    return SelectText(tbPtr, selLast);
}

/*ARGSUSED*/
static int
SelectionToOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;         /* Not used. */
    int objc;
    Tcl_Obj *CONST *objv;
{
    int textPos;

    if (GetIndexFromObj(interp, tbPtr, objv[3], &textPos) != TCL_OK) {
        return TCL_ERROR;
    }
    return SelectText(tbPtr, textPos);
}


static Blt_OpSpec selectionOps[] =
{
    {"adjust", 1, (Blt_Op)SelectionAdjustOp, 4, 4, "index",},
    {"clear", 1, (Blt_Op)SelectionClearOp, 3, 3, "",},
    {"from", 1, (Blt_Op)SelectionFromOp, 4, 4, "index"},
    {"present", 1, (Blt_Op)SelectionPresentOp, 3, 3, ""},
    {"range", 1, (Blt_Op)SelectionRangeOp, 5, 5, "start end",},
    {"to", 1, (Blt_Op)SelectionToOp, 4, 4, "index"},
};

static int nSelectionOps = sizeof(selectionOps) / sizeof(Blt_OpSpec);

/*
 *      This procedure handles the individual options for text
 *      selections.  The selected text is designated by start and end
 *      indices into the text pool.  The selected segment has both a
 *      anchored and unanchored ends.  The following selection
 *      operations are implemented:
 *
 *        "adjust"      - resets either the first or last index
 *                        of the selection.
 *        "clear"       - clears the selection. Sets first/last
 *                        indices to -1.
 *        "from"        - sets the index of the selection anchor.
 *        "present"     - return "1" if a selection is available,
 *                        "0" otherwise.
 *        "range"       - sets the first and last indices.
 *        "to"          - sets the index of the un-anchored end.
 */
static int
SelectionOp(tbPtr, interp, objc, objv)
    Textbox *tbPtr;
    Tcl_Interp *interp;
    int objc;
    Tcl_Obj *CONST *objv;
{
    Blt_Op proc;
    int result;

    proc = Blt_GetOpFromObj(interp, nSelectionOps, selectionOps, BLT_OP_ARG2, 
        objc, objv, 0);
    if (proc == NULL) {
        return TCL_ERROR;
    }
    result = (*proc) (tbPtr, interp, objc, objv);
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TextboxCmd --
 *
 *      This procedure handles entry operations.
 *
 * Results:
 *      A standard Tcl result.
 *
 *----------------------------------------------------------------------
 */
static Blt_OpSpec comboOps[] =
{
    {"apply", 1, (Blt_Op)ApplyOp, 2, 2, "",},
    {"cancel", 2, (Blt_Op)CancelOp, 2, 2, "",},
    {"cget", 2, (Blt_Op)CgetOp, 3, 3, "value",},
    {"configure", 2, (Blt_Op)ConfigureOp, 2, 0, "?option value...?",},
    {"delete", 1, (Blt_Op)DeleteOp, 3, 4, "first ?last?"},
    {"icursor", 2, (Blt_Op)IcursorOp, 3, 3, "index"},
    {"index", 3, (Blt_Op)IndexOp, 3, 3, "index"},
    {"insert", 3, (Blt_Op)InsertOp, 4, 4, "index string"},
    {"selection", 1, (Blt_Op)SelectionOp, 2, 0, "args"},
};
static int nComboOps = sizeof(comboOps) / sizeof(Blt_OpSpec);

static int
TextboxCmd(clientData, interp, objc, objv)
    ClientData clientData;
    Tcl_Interp *interp;
    int objc;
    Tcl_Obj *CONST *objv;
{
    Textbox *tbPtr = clientData;
    Blt_Op proc;
    int result;

    proc = Blt_GetOpFromObj(interp, nComboOps, comboOps, BLT_OP_ARG1, objc, 
        objv, 0);
    if (proc == NULL) {
        return TCL_ERROR;
    }
    result = (*proc) (tbPtr, interp, objc, objv);
    return result;
}

#endif