diff --git a/src/components/structures/LoggedInView.js b/src/components/structures/LoggedInView.js
index cc15df4edc..d6b374aac8 100644
--- a/src/components/structures/LoggedInView.js
+++ b/src/components/structures/LoggedInView.js
@@ -98,12 +98,17 @@ const LoggedInView = React.createClass({
             vertical: "mx_ResizeHandle_vertical",
             reverse: "mx_ResizeHandle_reverse"
         };
-        const collapseToggleSize = 260 - 50;
+        const config = {
+            toggleSize: 260 - 50,
+            onCollapsed: (collapsed) => {
+                this.setState({collapseLhs: collapsed});
+            }
+        };
         makeResizeable(
             this.resizeContainer,
             classNames,
             CollapseDistributor,
-            collapseToggleSize);
+            config);
     },
 
     componentWillMount: function() {
@@ -524,7 +529,7 @@ const LoggedInView = React.createClass({
                 <DragDropContext onDragEnd={this._onDragEnd}>
                     <div ref={(div) => this.resizeContainer = div} className={bodyClasses}>
                         <LeftPanel
-                            collapsed={this.props.collapseLhs || false}
+                            collapsed={this.props.collapseLhs || this.state.collapseLhs || false}
                             disabled={this.props.leftDisabled}
                         />
                         <ResizeHandle/>
diff --git a/src/resizer/distributors.js b/src/resizer/distributors.js
index 5a6e0f924a..0d13360ef4 100644
--- a/src/resizer/distributors.js
+++ b/src/resizer/distributors.js
@@ -17,18 +17,25 @@ class FixedDistributor {
 
 
 class CollapseDistributor extends FixedDistributor {
-    constructor(container, items, handleIndex, direction, sizer, toggleSize) {
+    constructor(container, items, handleIndex, direction, sizer, config) {
         super(container, items, handleIndex, direction, sizer);
-        this.toggleSize = toggleSize;
+        this.toggleSize = config && config.toggleSize;
+        this.onCollapsed = config && config.onCollapsed;
     }
 
     resize(offset) {
         let newSize = offset - this.sizer.getItemOffset(this.item);
         if (newSize < this.toggleSize) {
             this.item.classList.add("collapsed");
+            if (this.onCollapsed) {
+                this.onCollapsed(true, this.item);
+            }
         }
         else {
             this.item.classList.remove("collapsed");
+            if (this.onCollapsed) {
+                this.onCollapsed(false, this.item);
+            }
         }
         super.resize(newSize);
     }