GtkScrolledWindow: Bug 766569 - Make propagation of natural child sizes optional

Making propagation of child natural sizes mandatory (or default, even) was
evidently a mistake as this causes dynamic content in a scrolled window
to resize it's parent when the scrolled window is competing for space
with an adjacent widget.

This patch instead adds API to control whether natural width and
height of the child should be propagated through the scrolled windows
size requests.

diff --git a/docs/reference/gtk/gtk3-sections.txt b/docs/reference/gtk/gtk3-sections.txt
index 98641e25512ef24e739fc0cfd638bfed1567e858..e6a4147d07e702a89dcc63505028d5a762ce1c79 100644 (file)
--- a/docs/reference/gtk/gtk3-sections.txt
+++ b/docs/reference/gtk/gtk3-sections.txt
@@ -3239,6 +3239,10 @@ gtk_scrolled_window_set_capture_button_press
 gtk_scrolled_window_get_capture_button_press
 gtk_scrolled_window_set_overlay_scrolling
 gtk_scrolled_window_get_overlay_scrolling
+gtk_scrolled_window_set_propagate_natural_width
+gtk_scrolled_window_get_propagate_natural_width
+gtk_scrolled_window_set_propagate_natural_height
+gtk_scrolled_window_get_propagate_natural_height
 
 <SUBSECTION Standard>
 GTK_SCROLLED_WINDOW

diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index 082a0dcf205681b7691f2484041c67642f0e7153..b974987d27688be22fc8281c091ab776e25c27f2 100644 (file)
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -233,14 +233,16 @@ struct _GtkScrolledWindowPrivate
   GtkCornerType  window_placement;
   guint16  shadow_type;
 
-  guint    hscrollbar_policy      : 2;
-  guint    vscrollbar_policy      : 2;
-  guint    hscrollbar_visible     : 1;
-  guint    vscrollbar_visible     : 1;
-  guint    focus_out              : 1; /* used by ::move-focus-out implementation */
-  guint    overlay_scrolling      : 1;
-  guint    use_indicators         : 1;
-  guint    auto_added_viewport    : 1;
+  guint    hscrollbar_policy        : 2;
+  guint    vscrollbar_policy        : 2;
+  guint    hscrollbar_visible       : 1;
+  guint    vscrollbar_visible       : 1;
+  guint    focus_out                : 1; /* used by ::move-focus-out implementation */
+  guint    overlay_scrolling        : 1;
+  guint    use_indicators           : 1;
+  guint    auto_added_viewport      : 1;
+  guint    propagate_natural_width  : 1;
+  guint    propagate_natural_height : 1;
 
   gint     min_content_width;
   gint     min_content_height;
@@ -303,6 +305,8 @@ enum {
   PROP_OVERLAY_SCROLLING,
   PROP_MAX_CONTENT_WIDTH,
   PROP_MAX_CONTENT_HEIGHT,
+  PROP_PROPAGATE_NATURAL_WIDTH,
+  PROP_PROPAGATE_NATURAL_HEIGHT,
   NUM_PROPERTIES
 };
 
@@ -739,6 +743,42 @@ gtk_scrolled_window_class_init (GtkScrolledWindowClass *class)
                         -1, G_MAXINT, -1,
                         GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
 
+  /**
+   * GtkScrolledWindow:propagate-natural-width:
+   *
+   * Whether the natural width of the child should be calculated and propagated
+   * through the scrolled windows requested natural width.
+   *
+   * This is useful in cases where an attempt should be made to allocate exactly
+   * enough space for the natural size of the child.
+   *
+   * Since: 3.22
+   */
+  properties[PROP_PROPAGATE_NATURAL_WIDTH] =
+      g_param_spec_boolean ("propagate-natural-width",
+                            P_("Propagate Natural Width"),
+                            P_("Propagate Natural Width"),
+                            FALSE,
+                            GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+
+  /**
+   * GtkScrolledWindow:propagate-natural-height:
+   *
+   * Whether the natural height of the child should be calculated and propagated
+   * through the scrolled windows requested natural height.
+   *
+   * This is useful in cases where an attempt should be made to allocate exactly
+   * enough space for the natural size of the child.
+   *
+   * Since: 3.22
+   */
+  properties[PROP_PROPAGATE_NATURAL_HEIGHT] =
+      g_param_spec_boolean ("propagate-natural-height",
+                            P_("Propagate Natural Height"),
+                            P_("Propagate Natural Height"),
+                            FALSE,
+                            GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+
   g_object_class_install_properties (gobject_class, NUM_PROPERTIES, properties);
 
   /**
@@ -1798,7 +1838,8 @@ gtk_scrolled_window_measure (GtkCssGadget   *gadget,
                                           &min_child_size,
                                           &nat_child_size);
 
-         natural_req.width += nat_child_size;
+         if (priv->propagate_natural_width)
+           natural_req.width += nat_child_size;
 
          if (priv->hscrollbar_policy == GTK_POLICY_NEVER)
            {
@@ -1819,7 +1860,8 @@ gtk_scrolled_window_measure (GtkCssGadget   *gadget,
                                            &min_child_size,
                                            &nat_child_size);
 
-         natural_req.height += nat_child_size;
+         if (priv->propagate_natural_height)
+           natural_req.height += nat_child_size;
 
          if (priv->vscrollbar_policy == GTK_POLICY_NEVER)
            {
@@ -1836,6 +1878,10 @@ gtk_scrolled_window_measure (GtkCssGadget   *gadget,
        }
     }
 
+  /* Ensure we make requests with natural size >= minimum size */
+  natural_req.height = MAX (minimum_req.height, natural_req.height);
+  natural_req.width  = MAX (minimum_req.width,  natural_req.width);
+
   /*
    * Now add to the requisition any additional space for surrounding scrollbars
    * and the special scrollable border.
@@ -2847,6 +2893,14 @@ gtk_scrolled_window_set_property (GObject      *object,
       gtk_scrolled_window_set_max_content_height (scrolled_window,
                                                   g_value_get_int (value));
       break;
+    case PROP_PROPAGATE_NATURAL_WIDTH:
+      gtk_scrolled_window_set_propagate_natural_width (scrolled_window,
+                                                      g_value_get_boolean (value));
+      break;
+    case PROP_PROPAGATE_NATURAL_HEIGHT:
+      gtk_scrolled_window_set_propagate_natural_height (scrolled_window,
+                                                      g_value_get_boolean (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -2905,6 +2959,12 @@ gtk_scrolled_window_get_property (GObject    *object,
     case PROP_MAX_CONTENT_HEIGHT:
       g_value_set_int (value, priv->max_content_height);
       break;
+    case PROP_PROPAGATE_NATURAL_WIDTH:
+      g_value_set_boolean (value, priv->propagate_natural_width);
+      break;
+    case PROP_PROPAGATE_NATURAL_HEIGHT:
+      g_value_set_boolean (value, priv->propagate_natural_height);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -4731,3 +4791,101 @@ gtk_scrolled_window_get_max_content_height (GtkScrolledWindow *scrolled_window)
 
   return scrolled_window->priv->max_content_height;
 }
+
+/**
+ * gtk_scrolled_window_set_propagate_natural_width:
+ * @scrolled_window: a #GtkScrolledWindow
+ * @propagate: whether to propagate natural width
+ *
+ * Sets whether the natural width of the child should be calculated and propagated
+ * through the scrolled windows requested natural width.
+ *
+ * Since: 3.22
+ */
+void
+gtk_scrolled_window_set_propagate_natural_width (GtkScrolledWindow *scrolled_window,
+                                                gboolean           propagate)
+{
+  GtkScrolledWindowPrivate *priv;
+
+  g_return_if_fail (GTK_IS_SCROLLED_WINDOW (scrolled_window));
+
+  priv = scrolled_window->priv;
+
+  propagate = !!propagate;
+
+  if (priv->propagate_natural_width != propagate)
+    {
+      priv->propagate_natural_width = propagate;
+      g_object_notify_by_pspec (G_OBJECT (scrolled_window), properties [PROP_PROPAGATE_NATURAL_WIDTH]);
+      gtk_widget_queue_resize (GTK_WIDGET (scrolled_window));
+    }
+}
+
+/**
+ * gtk_scrolled_window_get_propagate_natural_width:
+ * @scrolled_window: a #GtkScrolledWindow
+ *
+ * Reports whether the natural width of the child will be calculated and propagated
+ * through the scrolled windows requested natural width.
+ *
+ * Returns: whether natural width propagation is enabled.
+ *
+ * Since: 3.22
+ */
+gint
+gtk_scrolled_window_get_propagate_natural_width (GtkScrolledWindow *scrolled_window)
+{
+  g_return_val_if_fail (GTK_IS_SCROLLED_WINDOW (scrolled_window), -1);
+
+  return scrolled_window->priv->propagate_natural_width;
+}
+
+/**
+ * gtk_scrolled_window_set_propagate_natural_height:
+ * @scrolled_window: a #GtkScrolledWindow
+ * @propagate: whether to propagate natural height
+ *
+ * Sets whether the natural height of the child should be calculated and propagated
+ * through the scrolled windows requested natural height.
+ *
+ * Since: 3.22
+ */
+void
+gtk_scrolled_window_set_propagate_natural_height (GtkScrolledWindow *scrolled_window,
+                                                gboolean           propagate)
+{
+  GtkScrolledWindowPrivate *priv;
+
+  g_return_if_fail (GTK_IS_SCROLLED_WINDOW (scrolled_window));
+
+  priv = scrolled_window->priv;
+
+  propagate = !!propagate;
+
+  if (priv->propagate_natural_height != propagate)
+    {
+      priv->propagate_natural_height = propagate;
+      g_object_notify_by_pspec (G_OBJECT (scrolled_window), properties [PROP_PROPAGATE_NATURAL_HEIGHT]);
+      gtk_widget_queue_resize (GTK_WIDGET (scrolled_window));
+    }
+}
+
+/**
+ * gtk_scrolled_window_get_propagate_natural_height:
+ * @scrolled_window: a #GtkScrolledWindow
+ *
+ * Reports whether the natural height of the child will be calculated and propagated
+ * through the scrolled windows requested natural height.
+ *
+ * Returns: whether natural height propagation is enabled.
+ *
+ * Since: 3.22
+ */
+gint
+gtk_scrolled_window_get_propagate_natural_height (GtkScrolledWindow *scrolled_window)
+{
+  g_return_val_if_fail (GTK_IS_SCROLLED_WINDOW (scrolled_window), -1);
+
+  return scrolled_window->priv->propagate_natural_height;
+}

diff --git a/gtk/gtkscrolledwindow.h b/gtk/gtkscrolledwindow.h
index 0aca3ad370b963d65de51ff74429bcd9068d276a..1b8d5cdb3ff30579d77ac27fe087c0efa208884a 100644 (file)
--- a/gtk/gtkscrolledwindow.h
+++ b/gtk/gtkscrolledwindow.h
@@ -226,6 +226,18 @@ void           gtk_scrolled_window_set_max_content_height (GtkScrolledWindow *sc
 GDK_AVAILABLE_IN_3_22
 gint           gtk_scrolled_window_get_max_content_height (GtkScrolledWindow *scrolled_window);
 
+GDK_AVAILABLE_IN_3_22
+void           gtk_scrolled_window_set_propagate_natural_width  (GtkScrolledWindow *scrolled_window,
+                                                                gboolean           propagate);
+GDK_AVAILABLE_IN_3_22
+gboolean       gtk_scrolled_window_get_propagate_natural_width  (GtkScrolledWindow *scrolled_window);
+
+GDK_AVAILABLE_IN_3_22
+void           gtk_scrolled_window_set_propagate_natural_height (GtkScrolledWindow *scrolled_window,
+                                                                gboolean           propagate);
+GDK_AVAILABLE_IN_3_22
+gboolean       gtk_scrolled_window_get_propagate_natural_height (GtkScrolledWindow *scrolled_window);
+
 G_END_DECLS