Deselect message history message when topic selection changes

Fixes #93

app/src/actions/Sidebar.ts

@@ -1,6 +1,7 @@
 import * as q from '../../../backend/src/Model'
-import { Dispatch } from 'redux'
+import { ActionTypes } from '../reducers/Sidebar'
 import { AppState } from '../reducers'
+import { Dispatch } from 'redux'
 import { makePublishEvent, rendererEvents } from '../../../events'
 
 export const clearRetainedTopic = () => (dispatch: Dispatch<any>, getState: () => AppState) => {
@@ -12,6 +13,13 @@ export const clearRetainedTopic = () => (dispatch: Dispatch<any>, getState: () =
   dispatch(clearTopic(selectedTopic, false))
 }
 
+export const setCompareMessage = (message?: q.Message) => (dispatch: Dispatch<any>) => {
+  dispatch({
+    message,
+    type: ActionTypes.SIDEBAR_SET_COMPARE_MESSAGE,
+  })
+}
+
 export const clearTopic = (topic: q.TreeNode<any>, recursive: boolean, subtopicClearLimit = 50) => (dispatch: Dispatch<any>, getState: () => AppState)  => {
   const { connectionId } = getState().connection
   if (!connectionId) {
@@ -25,7 +33,6 @@ export const clearTopic = (topic: q.TreeNode<any>, recursive: boolean, subtopicC
     retain: true,
     qos: 0 as 0,
   }
-  console.log('deleting', topic.path())
   rendererEvents.emit(publishEvent, mqttMessage)
 
   if (recursive) {

app/src/actions/Tree.ts

@@ -1,5 +1,6 @@
 import * as q from '../../../backend/src/Model'
 import { ActionTypes } from '../reducers/Tree'
+import { ActionTypes as SidebarActionTypes } from '../reducers/Sidebar'
 import { AnyAction, Dispatch } from 'redux'
 import { AppState } from '../reducers'
 import { batchActions } from 'redux-batched-actions'
@@ -40,6 +41,11 @@ const debouncedSelectTopic = debounce((topic: q.TreeNode<TopicViewModel>, dispat
     type: ActionTypes.TREE_SELECT_TOPIC,
   }
 
+  dispatch({
+    type: SidebarActionTypes.SIDEBAR_SET_COMPARE_MESSAGE,
+    message: undefined,
+  })
+
   if (setTopicDispatch) {
     dispatch(batchActions([selectTreeTopicDispatch, setTopicDispatch]))
   } else {