gtkentry.c

gtk是linux一款强大的夸平台的图形化开发工具

	 {
	    gtk_paint_flat_box (widget->style, drawable, 
				selected_state, GTK_SHADOW_NONE,
				NULL, widget, "text",
				INNER_BORDER + selection_start_xoffset,
				INNER_BORDER,
				selection_end_xoffset - selection_start_xoffset,
				height - 2*INNER_BORDER);
	    gdk_draw_text_wc (drawable, widget->style->font,
			      widget->style->fg_gc[selected_state],
			      INNER_BORDER + selection_start_xoffset, y,
			      toprint + selection_start_pos - start_pos,
			      selection_end_pos - selection_start_pos);
	 }	    
       
       if (selection_end_pos < end_pos)
	 gdk_draw_text_wc (drawable, widget->style->font,
			   widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
			   INNER_BORDER + selection_end_xoffset, y,
			   toprint + selection_end_pos - start_pos,
			   end_pos - selection_end_pos);
       /* free the space allocated for the stars if it's neccessary. */
      if (!editable->visible)
	g_free (toprint);

      if (editable->editable)
	gtk_entry_draw_cursor_on_drawable (entry, drawable);

      if (use_backing_pixmap)
	gdk_draw_pixmap(entry->text_area,
			widget->style->fg_gc[GTK_STATE_NORMAL],
			entry->backing_pixmap,
			0, 0, 0, 0, width, height);	  
    }
}

static void
gtk_entry_draw_cursor (GtkEntry *entry)
{
  g_return_if_fail (entry != NULL);
  g_return_if_fail (GTK_IS_ENTRY (entry));

  gtk_entry_draw_cursor_on_drawable (entry, entry->text_area);
}

static void
gtk_entry_draw_cursor_on_drawable (GtkEntry *entry, GdkDrawable *drawable)
{
  GtkWidget *widget;
  GtkEditable *editable;
  gint xoffset;
  gint text_area_height;

  g_return_if_fail (entry != NULL);
  g_return_if_fail (GTK_IS_ENTRY (entry));

  if (GTK_WIDGET_DRAWABLE (entry))
    {
      widget = GTK_WIDGET (entry);
      editable = GTK_EDITABLE (entry);

      xoffset = INNER_BORDER + entry->char_offset[editable->current_pos];
      xoffset -= entry->scroll_offset;

      gdk_window_get_size (entry->text_area, NULL, &text_area_height);

      if (GTK_WIDGET_HAS_FOCUS (widget) &&
	  (editable->selection_start_pos == editable->selection_end_pos))
	{
	  gdk_draw_line (drawable, widget->style->fg_gc[GTK_STATE_NORMAL], 
			 xoffset, INNER_BORDER,
			 xoffset, text_area_height - INNER_BORDER);
	}
      else
	{
	  gint yoffset = 
	    (text_area_height - 
	     (widget->style->font->ascent + widget->style->font->descent)) / 2
	    + widget->style->font->ascent;

	  gtk_paint_flat_box (widget->style, drawable,
			      GTK_WIDGET_STATE(widget), GTK_SHADOW_NONE,
			      NULL, widget, "entry_bg", 
			      xoffset, INNER_BORDER, 
			      1, text_area_height - INNER_BORDER);
	  
	  /* Draw the character under the cursor again
	   */
	  if ((editable->current_pos < entry->text_length) &&
	      (editable->selection_start_pos == editable->selection_end_pos))
	    {
	      GdkWChar c = editable->visible ?
		                 *(entry->text + editable->current_pos) :
		                 '*';
	      
	      gdk_draw_text_wc (drawable, widget->style->font,
				widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
				xoffset, yoffset, &c, 1);
	    }
	}


#ifdef USE_XIM
      if (GTK_WIDGET_HAS_FOCUS(widget) && gdk_im_ready() && editable->ic && 
	  (gdk_ic_get_style (editable->ic) & GDK_IM_PREEDIT_POSITION))
	{
	  editable->ic_attr->spot_location.x = xoffset;
	  editable->ic_attr->spot_location.y =
	    (text_area_height + (widget->style->font->ascent
	        - widget->style->font->descent) + 1) / 2;

	  gdk_ic_set_attr (editable->ic,
	      		   editable->ic_attr, GDK_IC_SPOT_LOCATION);
	}
#endif 
    }
}

static void
gtk_entry_queue_draw (GtkEntry *entry)
{
  g_return_if_fail (entry != NULL);
  g_return_if_fail (GTK_IS_ENTRY (entry));

  if (!entry->timer)
    entry->timer = gtk_timeout_add (DRAW_TIMEOUT, gtk_entry_timer, entry);
}

static gint
gtk_entry_timer (gpointer data)
{
  GtkEntry *entry;

  GDK_THREADS_ENTER ();

  entry = GTK_ENTRY (data);
  entry->timer = 0;
  gtk_entry_draw_text (entry);

  GDK_THREADS_LEAVE ();

  return FALSE;
}

static gint
gtk_entry_find_position (GtkEntry *entry,
			 gint      x)
{
  gint start = 0;
  gint end = entry->text_length;
  gint half;

  if (x <= 0)
    return 0;
  if (x >= entry->char_offset[end])
    return end;
  
  /* invariant - char_offset[start] <= x < char_offset[end] */

  while (start != end)
    {
      half = (start+end)/2;
      if (half == start)
	return half;
      else if (entry->char_offset[half] <= x)
	start = half;
      else
	end = half;
    }

  return start;
}

static gint
gtk_entry_position (GtkEntry *entry,
		    gint      x)
{
  return gtk_entry_find_position(entry, x);
}

static void
entry_adjust_scroll (GtkEntry *entry)
{
  gint xoffset, max_offset;
  gint text_area_width;

  g_return_if_fail (entry != NULL);
  g_return_if_fail (GTK_IS_ENTRY (entry));

  if (!entry->text_area)
    return;

  gdk_window_get_size (entry->text_area, &text_area_width, NULL);

  /* Display as much text as we can */
  max_offset = MAX(0, entry->char_offset[entry->text_length] - text_area_width);

  if (entry->scroll_offset > max_offset)
    entry->scroll_offset = max_offset;

  /* And make sure cursor is on screen */
  xoffset = entry->char_offset[GTK_EDITABLE(entry)->current_pos];
  xoffset -= entry->scroll_offset;

  if (xoffset < 0)
    entry->scroll_offset += xoffset;
  else if (xoffset > text_area_width)
    entry->scroll_offset += xoffset - text_area_width + 1;

  gtk_widget_queue_draw (GTK_WIDGET (entry));
}

static void
gtk_entry_grow_text (GtkEntry *entry)
{
  gint previous_size;
  gint i;

  g_return_if_fail (entry != NULL);
  g_return_if_fail (GTK_IS_ENTRY (entry));

  previous_size = entry->text_size;
  if (!entry->text_size)
    entry->text_size = 128;
  else
    entry->text_size *= 2;
  entry->text = g_realloc (entry->text, entry->text_size * sizeof(GdkWChar));
  entry->char_offset = g_realloc (entry->char_offset, 
				  entry->text_size * sizeof(guint));

  if (entry->text_length == 0)	/* initial allocation */
    {
      entry->char_offset[0] = 0;
    }

  for (i = previous_size; i < entry->text_size; i++)
    entry->text[i] = '\0';
}

static void
gtk_entry_insert_text (GtkEditable *editable,
		       const gchar *new_text,
		       gint         new_text_length,
		       gint        *position)
{
  GdkWChar *text;
  gint start_pos;
  gint end_pos;
  gint last_pos;
  gint max_length;
  gint i;

  guchar *new_text_nt;
  gint insertion_length;
  GdkWChar *insertion_text;
  
  GtkEntry *entry;
  GtkWidget *widget;
  
  g_return_if_fail (editable != NULL);
  g_return_if_fail (GTK_IS_ENTRY (editable));

  entry = GTK_ENTRY (editable);
  widget = GTK_WIDGET (editable);

  if ((entry->text_length == 0) && (entry->use_wchar == FALSE))
    {
      if (!GTK_WIDGET_REALIZED (widget))
	gtk_widget_ensure_style (widget);
      if ((widget->style) && (widget->style->font->type == GDK_FONT_FONTSET))
	entry->use_wchar = TRUE;
    }

  if (new_text_length < 0)
    {
      new_text_nt = (gchar *)new_text;
      new_text_length = strlen (new_text);
      if (new_text_length <= 0) return;
    }
  else if (new_text_length == 0)
    {
      return;
    }
  else
    {
      /* make a null-terminated copy of new_text */
      new_text_nt = g_new (gchar, new_text_length + 1);
      memcpy (new_text_nt, new_text, new_text_length);
      new_text_nt[new_text_length] = 0;
    }
    
  /* The algorithms here will work as long as, the text size (a
   * multiple of 2), fits into a guint16 but we specify a shorter
   * maximum length so that if the user pastes a very long text, there
   * is not a long hang from the slow X_LOCALE functions.  */
 
  if (entry->text_max_length == 0)
    max_length = 2047;
  else
    max_length = MIN (2047, entry->text_max_length);

  /* Convert to wide characters */
  insertion_text = g_new (GdkWChar, new_text_length);
  if (entry->use_wchar)
    insertion_length = gdk_mbstowcs (insertion_text, new_text_nt,
				     new_text_length);
  else
    for (insertion_length=0; new_text_nt[insertion_length]; insertion_length++)
      insertion_text[insertion_length] = new_text_nt[insertion_length];
  if (new_text_nt != (guchar *)new_text)
    g_free (new_text_nt);

  /* Make sure we do not exceed the maximum size of the entry. */
  if (insertion_length + entry->text_length > max_length)
    insertion_length = max_length - entry->text_length;

  /* Don't insert anything, if there was nothing to insert. */
  if (insertion_length <= 0)
    {
      g_free(insertion_text);
      return;
    }

  /* Make sure we are inserting at integral character position */
  start_pos = *position;
  if (start_pos < 0)
    start_pos = 0;
  else if (start_pos > entry->text_length)
    start_pos = entry->text_length;

  end_pos = start_pos + insertion_length;
  last_pos = insertion_length + entry->text_length;

  if (editable->selection_start_pos >= *position)
    editable->selection_start_pos += insertion_length;
  if (editable->selection_end_pos >= *position)
    editable->selection_end_pos += insertion_length;

  while (last_pos >= entry->text_size)
    gtk_entry_grow_text (entry);

  text = entry->text;
  for (i = last_pos - 1; i >= end_pos; i--)
    text[i] = text[i- (end_pos - start_pos)];
  for (i = start_pos; i < end_pos; i++)
    text[i] = insertion_text[i - start_pos];
  g_free (insertion_text);

  /* Fix up the the character offsets */
  
  if (GTK_WIDGET_REALIZED (entry))
    {
      gint offset = 0;
      
      for (i = last_pos; i >= end_pos; i--)
	entry->char_offset[i] 
	  = entry->char_offset[i - insertion_length];
      
      for (i=start_pos; i<end_pos; i++)
	{
	  entry->char_offset[i] = entry->char_offset[start_pos] + offset;
	  if (editable->visible)
	    {
	      offset += gdk_char_width_wc (GTK_WIDGET (entry)->style->font,
					   entry->text[i]);
	    }
	  else
	    {
	      offset += gdk_char_width (GTK_WIDGET (entry)->style->font, '*');
	    }
	}
      for (i = end_pos; i <= last_pos; i++)
	entry->char_offset[i] += offset;
    }

  entry->text_length += insertion_length;
  *position = end_pos;

  entry->text_mb_dirty = 1;
  gtk_entry_queue_draw (entry);
}

/* Recompute the x offsets of all characters in the buffer */
static void
gtk_entry_recompute_offsets (GtkEntry *entry)
{
  gint i;
  gint offset = 0;

  for (i=0; i<entry->text_length; i++)
    {
      entry->char_offset[i] = offset;
      if (GTK_EDITABLE (entry)->visible)
	{
	  offset += gdk_char_width_wc (GTK_WIDGET (entry)->style->font,
				       entry->text[i]);
	}
      else
	{
	  offset += gdk_char_width (GTK_WIDGET (entry)->style->font, '*');
	}
    }

  entry->char_offset[i] = offset;
}

static void
gtk_entry_delete_text (GtkEditable *editable,
		       gint         start_pos,
		       gint         end_pos)
{
  GdkWChar *text;
  gint deletion_length;
  gint i;

  GtkEntry *entry;
  
  g_return_if_fail (editable != NULL);
  g_return_if_fail (GTK_IS_ENTRY (editable));

  entry = GTK_ENTRY (editable);

  if (end_pos < 0)
    end_pos = entry->text_length;

  if (editable->selection_start_pos > start_pos)
    editable->selection_start_pos -= MIN(end_pos, editable->selection_start_pos) - start_pos;
  if (editable->selection_end_pos > start_pos)
    editable->selection_end_pos -= MIN(end_pos, editable->selection_end_pos) - start_pos;
  
  if ((start_pos < end_pos) &&
      (start_pos >= 0) &&
      (end_pos <= entry->text_length))
    {
      text = entry->text;
      deletion_length = end_pos - start_pos;

      /* Fix up the character offsets */
      if (GTK_WIDGET_REALIZED (entry))
	{
	  gint deletion_width = 
	    entry->char_offset[end_pos] - entry->char_offset[start_pos];

	  for (i = 0 ; i <= entry->text_length - end_pos; i++)
	    entry->char_offset[start_pos+i] = entry->char_offset[end_pos+i] - deletion_width;
	}

      for (i = end_pos; i < entry->text_length; i++)
        text[i - deletion_length] = text[i];

      for (i = entry->text_length - deletion_length; i < entry->text_length; i++)
        text[i] = '\0';

      entry->text_length -= deletion_length;
      editable->current_pos = start_pos;
    }

  entry->text_mb_dirty = 1;
  gtk_entry_queue_draw (entry);
}

static void
gtk_entry_update_text (GtkEditable *editable,