dash: Rework _adjustIconSize()

The current code uses the dash's height and current icon size to
calculate the new icon size. However, the height does not correctly
relate to the icon size while the icons are animating, in which
case the resulting icon size may be wrong.
Rework the function to be independent from the actual icon sizes,
so that a correct size is calculated even when called during an
animation.

https://bugzilla.gnome.org/show_bug.cgi?id=649248

diff --git a/js/ui/dash.js b/js/ui/dash.js
index 1a87b809ccabcd966ee9d93c87f3877b00fb087d..aa5f972703c40fc84512c9a0ead0d48d63786452 100644 (file)
--- a/js/ui/dash.js
+++ b/js/ui/dash.js
@@ -394,8 +394,18 @@ Dash.prototype = {
     },
 
     _adjustIconSize: function() {
-        let children = this._box.get_children();
-        if (children.length == 0) {
+        // For the icon size, we only consider children which are "proper"
+        // icons (i.e. ignoring drag placeholders) and which are not
+        // animating out (which means they will be destroyed at the end of
+        // the animation)
+        let iconChildren = this._box.get_children().filter(function(actor) {
+            return actor._delegate.child &&
+                   actor._delegate.child._delegate &&
+                   actor._delegate.child._delegate.icon &&
+                   !actor._delegate.animatingOut;
+        });
+
+        if (iconChildren.length == 0) {
             this._box.add_style_pseudo_class('empty');
             return;
         }
@@ -405,36 +415,39 @@ Dash.prototype = {
         if (this._maxHeight == -1)
             return;
 
-        // Hide actors which are about to be removed to not take
-        // them into account when adjusting the icon size ...
-        let hidingChildren = children.filter(function(actor) {
-            return actor._delegate.animatingOut;
-        });
 
-        for (let i = 0; i < hidingChildren.length; i++)
-            hidingChildren[i].hide();
+        let themeNode = this.actor.get_theme_node();
+        let maxAllocation = new Clutter.ActorBox({ x1: 0, y1: 0,
+                                                   x2: 42 /* whatever */,
+                                                   y2: this._maxHeight });
+        let maxContent = themeNode.get_content_box(maxAllocation);
+        let availHeight = maxContent.y2 - maxContent.y1;
+        let spacing = themeNode.get_length('spacing');
 
-        let iconChildren = children.filter(function(actor) {
-            return actor.visible &&
-                   actor._delegate.child &&
-                   actor._delegate.child._delegate &&
-                   actor._delegate.child._delegate.icon;
-        });
+
+        let firstIcon = iconChildren[0]._delegate.child._delegate.icon;
+
+        // Icons may be animating, so enforce the current icon size
+        // during the size request
+        let [currentWidth, currentHeight] = firstIcon.icon.get_size();
+
+        firstIcon.icon.set_size(this.iconSize, this.iconSize);
+        let [minHeight, natHeight] = iconChildren[0].get_preferred_height(-1);
+
+        firstIcon.icon.set_size(currentWidth, currentHeight);
 
 
-        // Compute the amount of extra space (or missing space) we have
-        // per icon with the current icon size
-        let [minHeight, natHeight] = this.actor.get_preferred_height(-1);
-        let diff = (this._maxHeight - natHeight) / iconChildren.length;
+        // Subtract icon padding and box spacing from the available height
+        availHeight -= iconChildren.length * (natHeight - this.iconSize) +
+                       (iconChildren.length - 1) * spacing;
 
-        for (let i = 0; i < hidingChildren.length; i++)
-            hidingChildren[i].show();
+        let availSize = availHeight / iconChildren.length;
 
         let iconSizes = [ 16, 22, 24, 32, 48, 64 ];
 
         let newIconSize = 16;
         for (let i = 0; i < iconSizes.length; i++) {
-            if (iconSizes[i] < this.iconSize + diff)
+            if (iconSizes[i] < availSize)
                 newIconSize = iconSizes[i];
         }