[gtk+] scrolledwindow: Ensure indicator windows are created at the right place

[Carlos Garnacho <carlosg src gnome org>]

commit 5a907cc094d518e5a69848ea573832bc0a7f11f1
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Feb 17 16:21:42 2015 +0100

    scrolledwindow: Ensure indicator windows are created at the right place
    
    At the time of creating the indicator window, the scrollbar allocation is
    poked and reused as the initial window dimensions. This usually happens
    on two circumstances, either initially (so a ::size-allocate is emitted,
    relocating the windows in the right places), or post-initialization when
    calling set_overlay_scrolling() (so the scrollbars already have a valid
    size allocation)
    
    However, if the scrolledwindow is unrealized, and later re-realized again,
    the scrollbars will already have a valid allocation, although 0,0 based
    due to being contained in the previous indicator window. This comes out
    wrong then, and the indicator window is given 0,0 based coordinates too.
    
    Fix this by refactoring the scrollbar allocation code out of size_allocate,
    and also use that given size at the time of creating the indicator windows,
    this will provide the right widget-relative allocation anytime.

 gtk/gtkscrolledwindow.c |  220 +++++++++++++++++++++++++++--------------------
 1 files changed, 125 insertions(+), 95 deletions(-)
---
diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index 9c6f1cc..ad40c08 100644
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -2482,19 +2482,133 @@ gtk_scrolled_window_allocate_child (GtkScrolledWindow *swindow,
 }
 
 static void
+gtk_scrolled_window_allocate_scrollbar (GtkScrolledWindow *scrolled_window,
+                                        GtkWidget         *scrollbar,
+                                        GtkAllocation     *allocation)
+{
+  GtkAllocation child_allocation, content_allocation;
+  GtkWidget *widget = GTK_WIDGET (scrolled_window);
+  gint sb_spacing, sb_height, sb_width;
+  gboolean scrollbars_within_bevel;
+  GtkScrolledWindowPrivate *priv;
+  GtkBorder padding, border;
+  GtkStyleContext *context;
+  GtkStateFlags state;
+
+  priv = scrolled_window->priv;
+
+  gtk_scrolled_window_allocate_child (scrolled_window, &content_allocation);
+  sb_spacing = _gtk_scrolled_window_get_scrollbar_spacing (scrolled_window);
+  gtk_widget_get_preferred_height (priv->hscrollbar, &sb_height, NULL);
+  gtk_widget_get_preferred_width (priv->vscrollbar, &sb_width, NULL);
+
+  context = gtk_widget_get_style_context (widget);
+  state = gtk_widget_get_state_flags (widget);
+
+  gtk_style_context_save (context);
+  gtk_style_context_add_class (context, GTK_STYLE_CLASS_FRAME);
+  gtk_widget_style_get (widget, "scrollbars-within-bevel", &scrollbars_within_bevel, NULL);
+  gtk_style_context_get_padding (context, state, &padding);
+  gtk_style_context_get_border (context, state, &border);
+  gtk_style_context_restore (context);
+
+  if (scrollbar == priv->hscrollbar)
+    {
+      child_allocation.x = content_allocation.x;
+
+      if (priv->window_placement == GTK_CORNER_TOP_LEFT ||
+         priv->window_placement == GTK_CORNER_TOP_RIGHT)
+        {
+          if (priv->use_indicators)
+           child_allocation.y = content_allocation.y + content_allocation.height - sb_height;
+          else
+           child_allocation.y = content_allocation.y + content_allocation.height + sb_spacing;
+        }
+      else
+        {
+          if (priv->use_indicators)
+           child_allocation.y = content_allocation.y;
+          else
+           child_allocation.y = content_allocation.y - sb_spacing - sb_height;
+        }
+
+      child_allocation.width = content_allocation.width;
+      child_allocation.height = sb_height;
+
+      if (priv->shadow_type != GTK_SHADOW_NONE)
+       {
+          if (!scrollbars_within_bevel)
+            {
+              child_allocation.x -= padding.left + border.left;
+              child_allocation.width += padding.left + padding.right + border.left + border.right;
+
+              if (priv->window_placement == GTK_CORNER_TOP_LEFT ||
+                  priv->window_placement == GTK_CORNER_TOP_RIGHT)
+                child_allocation.y += padding.bottom + border.bottom;
+              else
+                child_allocation.y -= padding.top + border.top;
+            }
+       }
+    }
+  else if (scrollbar == priv->vscrollbar)
+    {
+      if ((gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL &&
+          (priv->window_placement == GTK_CORNER_TOP_RIGHT ||
+           priv->window_placement == GTK_CORNER_BOTTOM_RIGHT)) ||
+         (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_LTR &&
+          (priv->window_placement == GTK_CORNER_TOP_LEFT ||
+           priv->window_placement == GTK_CORNER_BOTTOM_LEFT)))
+        {
+          if (priv->use_indicators)
+           child_allocation.x = content_allocation.x + content_allocation.width - sb_width;
+          else
+           child_allocation.x = content_allocation.x + content_allocation.width + sb_spacing;
+        }
+      else
+        {
+          if (priv->use_indicators)
+           child_allocation.x = content_allocation.x;
+          else
+           child_allocation.x = content_allocation.x - sb_spacing - sb_width;
+        }
+
+      child_allocation.y = content_allocation.y;
+      child_allocation.width = sb_width;
+      child_allocation.height = content_allocation.height;
+
+      if (priv->shadow_type != GTK_SHADOW_NONE)
+       {
+          if (!scrollbars_within_bevel)
+            {
+              child_allocation.y -= padding.top + border.top;
+             child_allocation.height += padding.top + padding.bottom + border.top + border.bottom;
+
+              if ((gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL &&
+                   (priv->window_placement == GTK_CORNER_TOP_RIGHT ||
+                    priv->window_placement == GTK_CORNER_BOTTOM_RIGHT)) ||
+                  (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_LTR &&
+                   (priv->window_placement == GTK_CORNER_TOP_LEFT ||
+                    priv->window_placement == GTK_CORNER_BOTTOM_LEFT)))
+                child_allocation.x += padding.right + border.right;
+              else
+                child_allocation.x -= padding.left + border.left;
+            }
+        }
+    }
+
+  *allocation = child_allocation;
+}
+
+static void
 gtk_scrolled_window_size_allocate (GtkWidget     *widget,
                                   GtkAllocation *allocation)
 {
   GtkScrolledWindow *scrolled_window;
   GtkScrolledWindowPrivate *priv;
-  GtkStyleContext *context;
-  GtkStateFlags state;
-  GtkBorder padding, border;
   GtkBin *bin;
   GtkAllocation relative_allocation;
   GtkAllocation child_allocation;
   GtkWidget *child;
-  gboolean scrollbars_within_bevel;
   gint sb_spacing;
   gint sb_width;
   gint sb_height;
@@ -2515,19 +2629,7 @@ gtk_scrolled_window_size_allocate (GtkWidget     *widget,
   gtk_widget_get_preferred_height (priv->hscrollbar, &sb_height, NULL);
   gtk_widget_get_preferred_width (priv->vscrollbar, &sb_width, NULL);
 
-  context = gtk_widget_get_style_context (widget);
-  state = gtk_widget_get_state_flags (widget);
-
-  gtk_style_context_save (context);
-  gtk_style_context_add_class (context, GTK_STYLE_CLASS_FRAME);
-
-  gtk_style_context_get_padding (context, state, &padding);
-  gtk_style_context_get_border (context, state, &border);
-
-  gtk_widget_style_get (widget, "scrollbars-within-bevel", &scrollbars_within_bevel, NULL);
-
   gtk_widget_set_allocation (widget, allocation);
-  gtk_style_context_restore (context);
 
   if (priv->hscrollbar_policy == GTK_POLICY_ALWAYS)
     priv->hscrollbar_visible = TRUE;
@@ -2742,41 +2844,9 @@ gtk_scrolled_window_size_allocate (GtkWidget     *widget,
   gtk_widget_set_child_visible (priv->hscrollbar, priv->hscrollbar_visible);
   if (priv->hscrollbar_visible)
     {
-      child_allocation.x = relative_allocation.x;
-      if (priv->window_placement == GTK_CORNER_TOP_LEFT ||
-         priv->window_placement == GTK_CORNER_TOP_RIGHT)
-        {
-          if (priv->use_indicators)
-           child_allocation.y = relative_allocation.y + relative_allocation.height - sb_height;
-          else
-           child_allocation.y = relative_allocation.y + relative_allocation.height + sb_spacing;
-        }
-      else
-        {
-          if (priv->use_indicators)
-           child_allocation.y = relative_allocation.y;
-          else
-           child_allocation.y = relative_allocation.y - sb_spacing - sb_height;
-        }
-
-      child_allocation.width = relative_allocation.width;
-      child_allocation.height = sb_height;
-
-      if (priv->shadow_type != GTK_SHADOW_NONE)
-       {
-          if (!scrollbars_within_bevel)
-            {
-              child_allocation.x -= padding.left + border.left;
-              child_allocation.width += padding.left + padding.right + border.left + border.right;
-
-              if (priv->window_placement == GTK_CORNER_TOP_LEFT ||
-                  priv->window_placement == GTK_CORNER_TOP_RIGHT)
-                child_allocation.y += padding.bottom + border.bottom;
-              else
-                child_allocation.y -= padding.top + border.top;
-            }
-       }
-
+      gtk_scrolled_window_allocate_scrollbar (scrolled_window,
+                                              priv->hscrollbar,
+                                              &child_allocation);
       if (priv->use_indicators)
         {
           gdk_window_move_resize (priv->hindicator.window,
@@ -2793,49 +2863,9 @@ gtk_scrolled_window_size_allocate (GtkWidget     *widget,
   gtk_widget_set_child_visible (priv->vscrollbar, priv->vscrollbar_visible);
   if (priv->vscrollbar_visible)
     {
-      if ((gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL &&
-          (priv->window_placement == GTK_CORNER_TOP_RIGHT ||
-           priv->window_placement == GTK_CORNER_BOTTOM_RIGHT)) ||
-         (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_LTR &&
-          (priv->window_placement == GTK_CORNER_TOP_LEFT ||
-           priv->window_placement == GTK_CORNER_BOTTOM_LEFT)))
-        {
-          if (priv->use_indicators)
-           child_allocation.x = relative_allocation.x + relative_allocation.width - sb_width;
-          else
-           child_allocation.x = relative_allocation.x + relative_allocation.width + sb_spacing;
-        }
-      else
-        {
-          if (priv->use_indicators)
-           child_allocation.x = relative_allocation.x;
-          else
-           child_allocation.x = relative_allocation.x - sb_spacing - sb_width;
-        }
-
-      child_allocation.y = relative_allocation.y;
-      child_allocation.width = sb_width;
-      child_allocation.height = relative_allocation.height;
-
-      if (priv->shadow_type != GTK_SHADOW_NONE)
-       {
-          if (!scrollbars_within_bevel)
-            {
-              child_allocation.y -= padding.top + border.top;
-             child_allocation.height += padding.top + padding.bottom + border.top + border.bottom;
-
-              if ((gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL &&
-                   (priv->window_placement == GTK_CORNER_TOP_RIGHT ||
-                    priv->window_placement == GTK_CORNER_BOTTOM_RIGHT)) ||
-                  (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_LTR &&
-                   (priv->window_placement == GTK_CORNER_TOP_LEFT ||
-                    priv->window_placement == GTK_CORNER_BOTTOM_LEFT)))
-                child_allocation.x += padding.right + border.right;
-              else
-                child_allocation.x -= padding.left + border.left;
-            }
-        }
-
+      gtk_scrolled_window_allocate_scrollbar (scrolled_window,
+                                              priv->vscrollbar,
+                                              &child_allocation);
       if (priv->use_indicators)
         {
           gdk_window_move_resize (priv->vindicator.window,
@@ -3707,7 +3737,7 @@ create_indicator_window (GtkScrolledWindow *scrolled_window,
   GdkWindowAttr attributes;
   gint attributes_mask;
 
-  gtk_widget_get_allocation (child, &allocation);
+  gtk_scrolled_window_allocate_scrollbar (scrolled_window, child, &allocation);
 
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.wclass = GDK_INPUT_OUTPUT;