Bug 1356285 - micro-optimization in richlistbox selectedIndex setter. r=Enn
MozReview-Commit-ID: 6fnhubnDUZ1
--- a/toolkit/content/widgets/listbox.xml
+++ b/toolkit/content/widgets/listbox.xml
@@ -98,17 +98,25 @@
if (this.selectedItems.length > 0)
return this.getIndexOfItem(this.selectedItems[0]);
return -1;
]]>
</getter>
<setter>
<![CDATA[
if (val >= 0) {
- this.selectItem(this.getItemAtIndex(val));
+ // This is a micro-optimization so that a call to getIndexOfItem or
+ // getItemAtIndex caused by _fireOnSelect (especially for derived
+ // widgets) won't loop the children.
+ this._selecting = {
+ item: this.getItemAtIndex(val),
+ index: val
+ };
+ this.selectItem(this._selecting.item);
+ delete this._selecting;
} else {
this.clearSelection();
this.currentItem = null;
}
]]>
</setter>
</property>
@@ -741,23 +749,31 @@
<property name="itemCount" readonly="true"
onget="return this.listBoxObject.getRowCount()"/>
<!-- ///////////////// nsIListBoxObject ///////////////// -->
<method name="getIndexOfItem">
<parameter name="item"/>
<body>
- return this.listBoxObject.getIndexOfItem(item);
+ <![CDATA[
+ if (this._selecting && this._selecting.item == item)
+ return this._selecting.index;
+ return this.listBoxObject.getIndexOfItem(item);
+ ]]>
</body>
</method>
<method name="getItemAtIndex">
<parameter name="index"/>
<body>
- return this.listBoxObject.getItemAtIndex(index);
+ <![CDATA[
+ if (this._selecting && this._selecting.index == index)
+ return this._selecting.item;
+ return this.listBoxObject.getItemAtIndex(index);
+ ]]>
</body>
</method>
<method name="ensureIndexIsVisible">
<parameter name="index"/>
<body>
return this.listBoxObject.ensureIndexIsVisible(index);
</body>
</method>
--- a/toolkit/content/widgets/richlistbox.xml
+++ b/toolkit/content/widgets/richlistbox.xml
@@ -170,26 +170,31 @@
<method name="getIndexOfItem">
<parameter name="aItem"/>
<body>
<![CDATA[
// don't search the children, if we're looking for none of them
if (aItem == null)
return -1;
-
+ if (this._selecting && this._selecting.item == aItem)
+ return this._selecting.index;
return this.children.indexOf(aItem);
]]>
</body>
</method>
<method name="getItemAtIndex">
<parameter name="aIndex"/>
<body>
- return this.children[aIndex] || null;
+ <![CDATA[
+ if (this._selecting && this._selecting.index == aIndex)
+ return this._selecting.item;
+ return this.children[aIndex] || null;
+ ]]>
</body>
</method>
<method name="ensureIndexIsVisible">
<parameter name="aIndex"/>
<body>
<![CDATA[
// work around missing implementation in scrollBoxObject
@@ -310,26 +315,23 @@
]]>
</body>
</method>
<!-- richlistbox specific -->
<property name="children" readonly="true">
<getter>
<![CDATA[
- var childNodes = [];
- var isReverse = this.dir == "reverse" && this._mayReverse;
- var child = isReverse ? this.lastChild : this.firstChild;
- var prop = isReverse ? "previousSibling" : "nextSibling";
- while (child) {
- if (child instanceof Components.interfaces.nsIDOMXULSelectControlItemElement)
- childNodes.push(child);
- child = child[prop];
+ let iface = Components.interfaces.nsIDOMXULSelectControlItemElement;
+ let children = Array.from(this.childNodes)
+ .filter(node => node instanceof iface);
+ if (this.dir == "reverse" && this._mayReverse) {
+ children.reverse();
}
- return childNodes;
+ return children;
]]>
</getter>
</property>
<field name="_builderListener" readonly="true">
<