gtktooltips.c

gtk是linux一款强大的夸平台的图形化开发工具

/* GTK - The GIMP Toolkit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

#include <stdlib.h>
#include <string.h>
#include <stdio.h>

#include "gtkmain.h"
#include "gtkwidget.h"
#include "gtkwindow.h"
#include "gtksignal.h"
#include "gtkstyle.h"
#include "gtktooltips.h"


#define DEFAULT_DELAY 500           /* Default delay in ms */

static void gtk_tooltips_class_init        (GtkTooltipsClass *klass);
static void gtk_tooltips_init              (GtkTooltips      *tooltips);
static void gtk_tooltips_destroy           (GtkObject        *object);

static gint gtk_tooltips_event_handler     (GtkWidget   *widget,
                                            GdkEvent    *event);
static void gtk_tooltips_widget_unmap      (GtkWidget   *widget,
                                            gpointer     data);
static void gtk_tooltips_widget_remove     (GtkWidget   *widget,
                                            gpointer     data);
static void gtk_tooltips_set_active_widget (GtkTooltips *tooltips,
                                            GtkWidget   *widget);
static gint gtk_tooltips_timeout           (gpointer     data);
static gint gtk_tooltips_paint_window      (GtkTooltips *tooltips);

static void gtk_tooltips_draw_tips         (GtkTooltips *tooltips);

static GtkDataClass *parent_class;
static const gchar  *tooltips_data_key = "_GtkTooltipsData";

GtkType
gtk_tooltips_get_type (void)
{
  static GtkType tooltips_type = 0;

  if (!tooltips_type)
    {
      static const GtkTypeInfo tooltips_info =
      {
	"GtkTooltips",
	sizeof (GtkTooltips),
	sizeof (GtkTooltipsClass),
	(GtkClassInitFunc) gtk_tooltips_class_init,
	(GtkObjectInitFunc) gtk_tooltips_init,
	/* reserved_1 */ NULL,
	/* reserved_2 */ NULL,
        (GtkClassInitFunc) NULL,
      };

      tooltips_type = gtk_type_unique (GTK_TYPE_DATA, &tooltips_info);
    }

  return tooltips_type;
}

static void
gtk_tooltips_class_init (GtkTooltipsClass *class)
{
  GtkObjectClass *object_class;

  object_class = (GtkObjectClass*) class;
  parent_class = gtk_type_class (GTK_TYPE_DATA);

  object_class->destroy = gtk_tooltips_destroy;
}

static void
gtk_tooltips_init (GtkTooltips *tooltips)
{
  tooltips->tip_window = NULL;
  tooltips->active_tips_data = NULL;
  tooltips->tips_data_list = NULL;
  tooltips->gc = NULL;
  tooltips->foreground = NULL;
  tooltips->background = NULL;
  
  tooltips->delay = DEFAULT_DELAY;
  tooltips->enabled = TRUE;
  tooltips->timer_tag = 0;
}

GtkTooltips *
gtk_tooltips_new (void)
{
  return gtk_type_new (GTK_TYPE_TOOLTIPS);
}

static void
gtk_tooltips_free_string (gpointer data, gpointer user_data)
{
  if (data)
    g_free (data);
}

static void
gtk_tooltips_destroy_data (GtkTooltipsData *tooltipsdata)
{
  g_free (tooltipsdata->tip_text);
  g_free (tooltipsdata->tip_private);
  if (tooltipsdata->row)
    {
      g_list_foreach (tooltipsdata->row, gtk_tooltips_free_string, 0);
      g_list_free (tooltipsdata->row);
    }
  gtk_signal_disconnect_by_data (GTK_OBJECT (tooltipsdata->widget),
 				 (gpointer) tooltipsdata);
  gtk_object_remove_data (GTK_OBJECT (tooltipsdata->widget), tooltips_data_key);
  gtk_widget_unref (tooltipsdata->widget);
  g_free (tooltipsdata);
}

static void
gtk_tooltips_destroy (GtkObject *object)
{
  GtkTooltips *tooltips = GTK_TOOLTIPS (object);
  GList *current;
  GtkTooltipsData *tooltipsdata;

  g_return_if_fail (tooltips != NULL);

  if (tooltips->timer_tag)
    {
      gtk_timeout_remove (tooltips->timer_tag);
      tooltips->timer_tag = 0;
    }

  if (tooltips->tips_data_list != NULL)
    {
      current = g_list_first (tooltips->tips_data_list);
      while (current != NULL)
	{
	  tooltipsdata = (GtkTooltipsData*) current->data;
	  current = current->next;
	  gtk_tooltips_widget_remove (tooltipsdata->widget, tooltipsdata);
	}
    }

  if (tooltips->tip_window)
    gtk_widget_destroy (tooltips->tip_window);

  if (tooltips->gc != NULL)
    {
      gdk_gc_destroy (tooltips->gc);
      tooltips->gc = NULL;
    }
}

void
gtk_tooltips_force_window (GtkTooltips *tooltips)
{
  g_return_if_fail (tooltips != NULL);
  g_return_if_fail (GTK_IS_TOOLTIPS (tooltips));

  if (!tooltips->tip_window)
    {
      tooltips->tip_window = gtk_window_new (GTK_WINDOW_POPUP);
      gtk_widget_set_app_paintable (tooltips->tip_window, TRUE);
      gtk_window_set_policy (GTK_WINDOW (tooltips->tip_window), FALSE, FALSE, TRUE);
      gtk_widget_set_name (tooltips->tip_window, "gtk-tooltips");
      gtk_signal_connect_object (GTK_OBJECT (tooltips->tip_window), 
				 "expose_event",
				 GTK_SIGNAL_FUNC (gtk_tooltips_paint_window), 
				 GTK_OBJECT (tooltips));
      gtk_signal_connect_object (GTK_OBJECT (tooltips->tip_window), 
				 "draw",
				 GTK_SIGNAL_FUNC (gtk_tooltips_paint_window), 
				 GTK_OBJECT (tooltips));

      gtk_signal_connect (GTK_OBJECT (tooltips->tip_window),
			  "destroy",
			  gtk_widget_destroyed,
			  &tooltips->tip_window);
    }
}

static void
gtk_tooltips_layout_text (GtkTooltips *tooltips, GtkTooltipsData *data)
{
  gchar *row_end, *text, *row_text, *break_pos;
  gint i, row_width, window_width = 0;
  size_t len;

  if (!tooltips->tip_window)
    gtk_tooltips_force_window (tooltips);

  if (data->row)
    {
      g_list_foreach (data->row, gtk_tooltips_free_string, 0);
      g_list_free (data->row);
    }
  data->row = 0;
  data->font = tooltips->tip_window->style->font;
  data->width = 0;

  text = data->tip_text;
  if (!text)
    return;

  while (*text)
    {
      row_end = strchr (text, '\n');
      if (!row_end)
       row_end = strchr (text, '\0');

      len = row_end - text + 1;
      row_text = g_new(gchar, len);
      memcpy (row_text, text, len - 1);
      row_text[len - 1] = '\0';

      /* now either adjust the window's width or shorten the row until
        it fits in the window */

      while (1)
       {
         row_width = gdk_string_width (data->font, row_text);
         if (!window_width)
           {
             /* make an initial guess at window's width: */

             if (row_width > gdk_screen_width () / 4)
               window_width = gdk_screen_width () / 4;
             else
               window_width = row_width;
           }
         if (row_width <= window_width)
           break;

         if (strchr (row_text, ' '))
           {
             /* the row is currently too wide, but we have blanks in
                the row so we can break it into smaller pieces */

             gint avg_width = row_width / strlen (row_text);

             i = window_width;
             if (avg_width)
               i /= avg_width;
             if ((size_t) i >= len)
               i = len - 1;

             break_pos = strchr (row_text + i, ' ');
             if (!break_pos)
               {
                 break_pos = row_text + i;
                 while (*--break_pos != ' ');
               }
             *break_pos = '\0';
           }
         else
           {
             /* we can't break this row into any smaller pieces, so
                we have no choice but to widen the window: */

             window_width = row_width;
             break;
           }
       }
      if (row_width > data->width)
       data->width = row_width;
      data->row = g_list_append (data->row, row_text);
      text += strlen (row_text);
      if (!*text)
       break;

      if (text[0] == '\n' && text[1])
       /* end of paragraph and there is more text to come */
       data->row = g_list_append (data->row, 0);
      ++text;  /* skip blank or newline */
    }
  data->width += 8;    /* leave some border */
}

void
gtk_tooltips_enable (GtkTooltips *tooltips)
{
  g_return_if_fail (tooltips != NULL);

  tooltips->enabled = TRUE;
}

void
gtk_tooltips_disable (GtkTooltips *tooltips)
{
  g_return_if_fail (tooltips != NULL);

  gtk_tooltips_set_active_widget (tooltips, NULL);