Merge pull request #1665 from matrix-org/luke/fix-matrix-chat-logged-…

…in-view-ref

Avoid NPEs by using ref method for collecting loggedInView in MatrixChat

src/components/structures/MatrixChat.js

@@ -1065,10 +1065,10 @@ export default React.createClass({
             // this if we are not scrolled up in the view. To find out, delegate to
             // the timeline panel. If the timeline panel doesn't exist, then we assume
             // it is safe to reset the timeline.
-            if (!self.refs.loggedInView) {
+            if (!self._loggedInView) {
                 return true;
             }
-            return self.refs.loggedInView.canResetTimelineInRoom(roomId);
+            return self._loggedInView.canResetTimelineInRoom(roomId);
         });
 
         cli.on('sync', function(state, prevState) {
@@ -1487,6 +1487,10 @@ export default React.createClass({
         return this.props.makeRegistrationUrl(params);
     },
 
+    _collectLoggedInView: function(ref) {
+        this._loggedInView = ref;
+    },
+
     render: function() {
         // console.log(`Rendering MatrixChat with view ${this.state.view}`);
 
@@ -1519,7 +1523,7 @@ export default React.createClass({
                  */
                 const LoggedInView = sdk.getComponent('structures.LoggedInView');
                 return (
-                   <LoggedInView ref="loggedInView" matrixClient={MatrixClientPeg.get()}
+                   <LoggedInView ref={this._collectLoggedInView} matrixClient={MatrixClientPeg.get()}
                         onRoomCreated={this.onRoomCreated}
                         onUserSettingsClose={this.onUserSettingsClose}
                         onRegistered={this.onRegistered}