gtk-changes-2-0.html

最新gtk中文资料集

    }
    static void gtk_label_class_init (GtkLabelClass *class)
    {
      GObjectClass *gobject_class = G_OBJECT_CLASS (class);
      
      gobject_class->finalize = gtk_label_finalize;
    }
</pre></div>
<p>
</p>
</li>
</ul></div>
<p>
</p>
</li>
<li>
<p>
The GtkObject::destroy signal can now be emitted multiple times on an object.
    ::destroy implementations should check that make sure that they take this
    into account, by checking to make sure that resources are there before
    freeing them. For example:
</p>
<div class="informalexample"><pre class="programlisting">
    if (object-&gt;foo_data)
      { 
        g_free (object-&gt;foo_data);
        object-&gt;foo_data = NULL;
      }
</pre></div>
<p>

    Also, ::destroy implementations have to release object references that
    the object holds. Code in finalize implementations such as:
</p>
<div class="informalexample"><pre class="programlisting">
    if (object-&gt;adjustment)
      {
        gtk_object_unref (object-&gt;adjustment);
        object-&gt;adjustment = NULL;
      }
</pre></div>
<p>
    have to be moved into the ::destroy implementations. The reason for doing
    this is that all object reference cycles should be broken at destruction 
    time.

    Because the ::destroy signal can be emitted multiple times, it no longer
    makes sense to check if a widget has been destroyed using the 
    <code class="function">GTK_OBJECT_DESTROYED()</code> macro, and this macro has been 
    removed. If catching destruction is still needed, it can be done with a 
    signal connection to ::destroy.
</p>
</li>
<li>
<p>
Signal system changes:
  The GTK+ 2.0 signal system merely proxies the <span class="structname">GSignal</span> 
  system now. For future usage, direct use of the 
  <span class="structname">GSignal</span> API is recommended,
  this avoids significant performance hits where <span class="structname">GtkArg</span>
  structures have to be converted into <span class="structname">GValue</span>s. For 
  language bindings, <span class="structname">GSignal</span>+<span class="structname">GClosure</span>
  provide a much more flexible and convenient mechanism to hook into signal 
  emissions or install class default handlers, so the old 
  <span class="structname">GtkSignal</span> API for language bindings is not
  supported anymore.
</p>
<p>
  Functions that got removed in the GTK+ signal API:
  <code class="function">gtk_signal_n_emissions()</code>, 
  <code class="function">gtk_signal_n_emissions_by_name()</code>,
  <code class="function">gtk_signal_set_funcs()</code>, 
  <code class="function">gtk_signal_handler_pending_by_id()</code>,
  <code class="function">gtk_signal_add_emission_hook()</code>, 
  <code class="function">gtk_signal_add_emission_hook_full()</code>,
  <code class="function">gtk_signal_remove_emission_hook()</code>, 
  <code class="function">gtk_signal_query()</code>.
  Also, the <span class="structname">GtkCallbackMarshal</span> argument to 
  <code class="function">gtk_signal_connect_full()</code> is
  not supported anymore.
  For many of the removed functions, similar variants are available
  in the <code class="function">g_signal_*</code> namespace.
  The <span class="structname">GSignal</span> system performs emissions in a 
  slightly different manner than the old <span class="structname">GtkSignal</span> 
  code. Signal handlers that are connected to signal "foo"
  on object "bar" while "foo" is being emitted, will not be called anymore
  during the emission they were connected within.
</p>
</li>
<li><p>
Inserting and deleting text in <span class="structname">GtkEntry</span> though 
  functions such as <code class="function">gtk_entry_insert_text()</code> now leave 
  the cursor at its original position in the text instead of moving it to 
  the location of the insertion/deletion.
</p></li>
<li><p>
The <em class="structfield"><code>label</code></em> field of <span class="structname">GtkFrame</span> 
  widgets has been removed (as part of a change to allow arbitrary widgets 
  in the title position). The text can now be retrieved with the new function 
  <code class="function">gtk_frame_get_text()</code>.
</p></li>
<li><p>
The 'font' and 'font_set' declarations in RC files are now ignored. There
  is a new 'font_name' field that holds the string form of a Pango font.
</p></li>
<li><p>
A number of types in GDK have become subclasses of 
  <span class="structname">GObject</span>. For the most part, this should not break 
  anyone's code. However, it's now possible/encouraged to use 
  <code class="function">g_object_ref()</code>/<code class="function">g_object_unref()</code> and
  other <span class="structname">GObject</span> features with these GDK types. The 
  converted types are:
  <span class="structname">GdkWindow</span>, <span class="structname">GdkDrawable</span>, 
  <span class="structname">GdkPixmap</span>, <span class="structname">GdkImage</span>, 
  <span class="structname">GdkGC</span>, <span class="structname">GdkDragContext</span>,
  <span class="structname">GdkColormap</span>.
</p></li>
<li><p>
All drawables including pixmaps used to have a type tag, the
  <span class="structname">GdkWindowType</span> enumeration, which included 
  <code class="literal">GDK_WINDOW_PIXMAP</code>.
  <span class="structname">GdkWindowType</span> is now a property of 
  <span class="structname">GdkWindow</span> <span class="emphasis"><em>only</em></span>, and there is 
  no <code class="literal">GDK_WINDOW_PIXMAP</code>. You can use the 
  <code class="function">GDK_IS_PIXMAP()</code> macro to see if you have a pixmap, if
  you need to know that.
</p></li>
<li><p>
<span class="structname">GtkStyle</span> and <span class="structname">GtkRcStyle</span> are 
  now subclasses of <span class="structname">GObject</span> as well.  This
  requires fairly extensive changes to theme engines, but
  shouldn't affect most other code.
</p></li>
<li><p>
<em class="structfield"><code>xthickness</code></em> and <em class="structfield"><code>ythickness</code></em> have moved from 
  <span class="structname">GtkStyleClass</span> to <span class="structname">GtkStyle</span>
  (from class to instance). This gives themes a bit more flexibility
  and is generally more of the Right Thing. You can trivially fix
  your code with <code class="literal">s/style-&gt;klass-&gt;xthickness/style-&gt;xthickness/g</code> and 
  same for <code class="literal">ythickness</code>.
</p></li>
<li><p>
Some <span class="structname">GtkStyle</span> <code class="function">draw_*</code> methods 
  have been removed (cross, oval, ramp) 
  and others have been added (expander, layout). This will require
  changes to theme engines.
</p></li>
<li><p>
If you were using private GDK types, they have been rearranged
  significantly. You shouldn't use private types. ;-) 
</p></li>
<li><p>
The visual for a widget, and also the default visual is now derived
  from the colormap for the widget and the default colormap.
  <code class="function">gtk_widget_set_visual()</code>, 
  <code class="function">gtk_widget_set_default_visual()</code>,
  <code class="function">gtk_widget_push_visual()</code> and 
  <code class="function">gtk_widget_pop_visual()</code> now do
  nothing. Since the visual always had to match that of the colormap,
  it is safe to simply delete all references to these functions.
</p></li>
<li>
<p>
A number of functions in GDK have been renamed for consistency and
  clarity. #defines to provide backwards compatibility have been
  included, but can be disabled by defining <code class="literal">GDK_DISABLE_DEPRECATED</code>.

</p>
<div class="informaltable"><table border="1">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>Old function</th>
<th>Defined As</th>
</tr></thead>
<tbody>
<tr>
<td><code class="function">gdk_draw_pixmap</code></td>
<td><code class="function">gdk_draw_drawable</code></td>
</tr>
<tr>
<td><code class="function">gdk_draw_bitmap</code></td>
<td><code class="function">gdk_draw_drawable</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_get_size</code></td>
<td><code class="function">gdk_drawable_get_size</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_get_type</code></td>
<td><code class="function">gdk_window_get_window_type</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_get_colormap</code></td>
<td><code class="function">gdk_drawable_get_colormap</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_set_colormap</code></td>
<td><code class="function">gdk_drawable_set_colormap</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_get_visual</code></td>
<td><code class="function">gdk_drawable_get_visual</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_ref</code></td>
<td><code class="function">gdk_drawable_ref</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_unref</code></td>
<td><code class="function">gdk_drawable_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_bitmap_ref</code></td>
<td><code class="function">gdk_drawable_ref</code></td>
</tr>
<tr>
<td><code class="function">gdk_bitmap_unref</code></td>
<td><code class="function">gdk_drawable_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_pixmap_ref</code></td>
<td><code class="function">gdk_drawable_ref</code></td>
</tr>
<tr>
<td><code class="function">gdk_pixmap_unref</code></td>
<td><code class="function">gdk_drawable_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_gc_destroy</code></td>
<td><code class="function">gdk_gc_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_image_destroy</code></td>
<td><code class="function">gdk_image_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_cursor_destroy</code></td>
<td><code class="function">gdk_cursor_unref</code></td>
</tr>
<tr>
<td><code class="function">gdk_window_copy_area(drawable,gc,x,y,source_drawable,source_x,source_y,width,height)</code></td>
<td><code class="function">gdk_draw_pixmap(drawable,gc,source_drawable,source_x,source_y,x,y,width,height)</code></td>
</tr>
<tr>
<td><code class="function">gdk_rgb_get_cmap</code></td>
<td><code class="function">gdk_rgb_get_colormap</code></td>
</tr>
</tbody>
</table></div>
<p>
  (Note that <code class="function">g_object_ref()</code> and 
  <code class="function">g_object_unref()</code> may be used for all of the above ref 
  and unref functions.)

  <code class="function">gtk_widget_popup()</code> was removed, it was only usable 
  for <span class="structname">GtkWindow</span>s, and there the same effect can be 
  achieved by <code class="function">gtk_window_move()</code> and
  <code class="function">gtk_widget_show()</code>.
</p>
</li>
<li><p>
<code class="function">gdk_pixmap_foreign_new()</code> no longer calls 
  <code class="function">XFreePixmap()</code> on the pixmap when the 
  <span class="structname">GdkPixmap</span> is finalized. This change corresponds
  to the behavior of <code class="function">gdk_window_foreign_new()</code>, and fixes 
  a lot of problems with code where the pixmap wasn't supposed to be freed. 
  If <code class="function">XFreePixmap()</code> is needed, it can be done using the
  destroy-notification facilities of <code class="function">g_object_set_data()</code>.
</p></li>
<li>
<p>
<span class="structname">GtkProgress</span>/<span class="structname">GtkProgressBar</span> 
  had serious problems in GTK+ 1.2.
</p>
<div class="itemizedlist"><ul type="circle">
<li><p>
Only 3 or 4 functions are really needed for 95% of progress interfaces; 
  <span class="structname">GtkProgress</span>/<span class="structname">GtkProgressBar</span> 
  had about 25 functions, and didn't even include these 3 or 4.
</p></li>
<li><p>
In activity mode, the API involves setting the adjustment 
    to any random value, just to have the side effect of 
    calling the progress bar update function - the adjustment
    is totally ignored in activity mode.
</p></li>
<li><p>
You set the activity step as a pixel value, which means to 
    set the activity step you basically need to connect to 
    size_allocate.
</p></li>
<li><p>