Refactor

app/index.html

@@ -22,10 +22,10 @@
           background-color: none;
         }
         25% {
-          background-color: #3f51b5;
+          background-color: #4f5781;
         }
         50% {
-          background-color: #3f51b5;
+          background-color: #4f5781;
         }
         100% {
           background-color: none;
@@ -38,11 +38,11 @@
           color: inherit;
         }
         25% {
-          background-color: #bfc9c8;
+          background-color: #c0c8c0;
           color: #000;
         }
         50% {
-          background-color: #bfc9c8;
+          background-color: #c0c8c0;
           color: #000;
         }
         100% {

app/src/actions/Sidebar.ts

@@ -2,7 +2,9 @@ import * as q from '../../../backend/src/Model'
 import { ActionTypes } from '../reducers/Sidebar'
 import { AppState } from '../reducers'
 import { Dispatch } from 'redux'
-import { makePublishEvent, rendererEvents } from '../../../events'
+import { clearTopic } from './clearTopic'
+
+export { clearTopic } from './clearTopic'
 
 export const clearRetainedTopic = () => (dispatch: Dispatch<any>, getState: () => AppState) => {
   const selectedTopic = getState().tree.get('selectedTopic')
@@ -19,38 +21,3 @@ export const setCompareMessage = (message?: q.Message) => (dispatch: Dispatch<an
     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) {
-    return
-  }
-
-  const publishEvent = makePublishEvent(connectionId)
-  const mqttMessage = {
-    topic: topic.path(),
-    payload: null,
-    retain: true,
-    qos: 0 as 0,
-  }
-  rendererEvents.emit(publishEvent, mqttMessage)
-
-  if (recursive) {
-    topic
-      .childTopics()
-      .filter(topic => Boolean(topic.message && topic.message.value))
-      .slice(0, subtopicClearLimit)
-      .forEach(topic => {
-        const mqttMessage = {
-          topic: topic.path(),
-          payload: null,
-          retain: true,
-          qos: 0 as 0,
-        }
-        rendererEvents.emit(publishEvent, mqttMessage)
-      })
-  }
-}

app/src/actions/Tree.ts

@@ -8,8 +8,10 @@ import { globalActions } from './'
 import { setTopic } from './Publish'
 import { TopicViewModel } from '../model/TopicViewModel'
 const debounce = require('lodash.debounce')
+export { clearTopic } from './clearTopic'
 
 export { moveSelectionUpOrDownwards, moveInward, moveOutward } from './visibleTreeTraversal'
+import { moveSelectionUpOrDownwards } from './visibleTreeTraversal'
 
 export const selectTopic = (topic: q.TreeNode<TopicViewModel>) => (
   dispatch: Dispatch<any>,

app/src/actions/clearTopic.ts

@@ -0,0 +1,41 @@
+import * as q from '../../../backend/src/Model'
+import { AppState } from '../reducers'
+import { Dispatch } from 'redux'
+import { makePublishEvent, rendererEvents } from '../../../events'
+import { moveSelectionUpOrDownwards } from './visibleTreeTraversal'
+
+export const clearTopic = (topic: q.TreeNode<any>, recursive: boolean, subtopicClearLimit = 50) => (
+  dispatch: Dispatch<any>,
+  getState: () => AppState
+) => {
+  dispatch(moveSelectionUpOrDownwards('next'))
+
+  const { connectionId } = getState().connection
+  if (!connectionId) {
+    return
+  }
+  const publishEvent = makePublishEvent(connectionId)
+  const mqttMessage = {
+    topic: topic.path(),
+    payload: null,
+    retain: true,
+    qos: 0 as 0,
+  }
+  rendererEvents.emit(publishEvent, mqttMessage)
+  if (recursive) {
+    topic
+      .childTopics()
+      .filter(topic => Boolean(topic.message && topic.message.value))
+      .slice(0, subtopicClearLimit)
+      .forEach((topic, idx) => {
+        const mqttMessage = {
+          topic: topic.path(),
+          payload: null,
+          retain: true,
+          qos: 0 as 0,
+        }
+        // Rate limit deletion
+        setTimeout(() => rendererEvents.emit(publishEvent, mqttMessage), 20 * idx)
+      })
+  }
+}

app/src/actions/visibleTreeTraversal.ts

@@ -13,6 +13,7 @@ export const moveSelectionUpOrDownwards = (direction: 'next' | 'previous') => (
   const state = getState()
   const selected = state.tree.get('selectedTopic')
   const tree = state.tree.get('tree')
+
   if (!selected || !tree) {
     if (tree) {
       dispatch(selectTopic(tree))

app/src/components/Layout/ContentView.tsx

@@ -1,7 +1,7 @@
 import * as React from 'react'
 import ChartPanel from '../ChartPanel'
 import ReactSplitPane from 'react-split-pane'
-import Tree from '../Tree/Tree'
+import Tree from '../Tree'
 import { AppState } from '../../reducers'
 import { ChartParameters } from '../../reducers/Charts'
 import { connect } from 'react-redux'

app/src/components/Layout/SearchBar.tsx

@@ -41,7 +41,13 @@ function SearchBar(props: {
     const tagElementIsNotBlacklisted =
       document.activeElement && tagNameBlacklist.indexOf(document.activeElement.tagName) === -1
 
-    if ((isCharacter || isAllowedControlCharacter) && !hasFocus && tagElementIsNotBlacklisted && hasConnection) {
+    if (
+      (isCharacter || isAllowedControlCharacter) &&
+      !event.defaultPrevented &&
+      !hasFocus &&
+      tagElementIsNotBlacklisted &&
+      hasConnection
+    ) {
       // Focus input field, no preventDefault the event will reach the input element after it has been focussed
       inputRef.current && inputRef.current.focus()
     }

app/src/components/Tree/TreeNode/TreeNodeSubnodes.tsx

@@ -1,10 +1,11 @@
-import * as q from '../../../../backend/src/Model'
+import * as q from '../../../../../backend/src/Model'
-import * as React from 'react'
+import React from 'react'
-import TreeNode from './TreeNode'
+import TreeNode from '.'
-import { SettingsState } from '../../reducers/Settings'
+import { SettingsState } from '../../../reducers/Settings'
-import { sortedNodes } from '../../sortedNodes'
+import { sortedNodes } from '../../../sortedNodes'
 import { Theme, withStyles } from '@material-ui/core'
-import { TopicViewModel } from '../../model/TopicViewModel'
+import { TopicViewModel } from '../../../model/TopicViewModel'
+import { treeActions } from '../../../actions'
 
 export interface Props {
   treeNode: q.TreeNode<TopicViewModel>
@@ -14,6 +15,7 @@ export interface Props {
   selectedTopic?: q.TreeNode<TopicViewModel>
   selectTopicAction: (treeNode: q.TreeNode<any>) => void
   settings: SettingsState
+  actions: typeof treeActions
 }
 
 interface State {
@@ -60,6 +62,7 @@ class TreeNodeSubnodes extends React.Component<Props, State> {
           lastUpdate={node.lastUpdate}
           selectTopicAction={this.props.selectTopicAction}
           settings={this.props.settings}
+          actions={this.props.actions}
         />
       )
     })

app/src/components/Tree/TreeNode/TreeNodeTitle.tsx

@@ -1,8 +1,8 @@
 import * as React from 'react'
-import * as q from '../../../../backend/src/Model'
+import * as q from '../../../../../backend/src/Model'
 import { withStyles, Theme } from '@material-ui/core'
-import { TopicViewModel } from '../../model/TopicViewModel'
+import { TopicViewModel } from '../../../model/TopicViewModel'
-import { Base64Message } from '../../../../backend/src/Model/Base64Message'
+import { Base64Message } from '../../../../../backend/src/Model/Base64Message'
 
 export interface TreeNodeProps extends React.HTMLAttributes<HTMLElement> {
   treeNode: q.TreeNode<TopicViewModel>

app/src/components/Tree/TreeNode/effects/useAnimationToIndicateTopicUpdate.tsx

@@ -0,0 +1,22 @@
+import React, { useEffect } from 'react'
+
+export function useAnimationToIndicateTopicUpdate(
+  lastUpdate: number,
+  selected: boolean,
+  setShowUpdateAnimation: React.Dispatch<React.SetStateAction<boolean>>,
+  showUpdateAnimation: boolean
+) {
+  useEffect(() => {
+    if (Date.now() - lastUpdate < 3000 && !selected) {
+      setShowUpdateAnimation(true)
+    }
+  }, [lastUpdate, selected])
+  useEffect(() => {
+    if (showUpdateAnimation) {
+      const timeout = setTimeout(() => setShowUpdateAnimation(false), 500)
+      return function cleanup() {
+        clearTimeout(timeout)
+      }
+    }
+  }, [showUpdateAnimation])
+}

app/src/components/Tree/TreeNode/effects/useDeleteKeyCallback.tsx

@@ -0,0 +1,17 @@
+import * as q from '../../../../../../backend/src/Model'
+import React, { useCallback } from 'react'
+import { KeyCodes } from '../../../../utils/KeyCodes'
+import { treeActions } from '../../../../actions'
+
+export function useDeleteKeyCallback(topic: q.TreeNode<any>, actions: typeof treeActions) {
+  return useCallback(
+    (event: React.KeyboardEvent) => {
+      if (event.keyCode === KeyCodes.delete || event.keyCode === KeyCodes.backspace) {
+        event.stopPropagation()
+        event.preventDefault()
+        actions.clearTopic(topic, true, 50)
+      }
+    },
+    [topic]
+  )
+}

app/src/components/Tree/TreeNode/effects/useIsAllowedToAutoExpandState.tsx

@@ -0,0 +1,14 @@
+import { Props } from '..'
+import { useEffect, useState } from 'react'
+
+export function useIsAllowedToAutoExpandState(props: Props): boolean {
+  const { settings, treeNode, isRoot } = props
+  const [isAllowedToAutoExpand, setAllowAutoExpand] = useState(false)
+  useEffect(() => {
+    const newIsAllowedToAutoExpand = isRoot || treeNode.edgeCount() <= settings.get('autoExpandLimit')
+    if (newIsAllowedToAutoExpand !== isAllowedToAutoExpand) {
+      setAllowAutoExpand(newIsAllowedToAutoExpand)
+    }
+  }, [treeNode.edgeCount(), settings.get('autoExpandLimit')])
+  return isAllowedToAutoExpand
+}

app/src/components/Tree/TreeNode/effects/useViewModelSubscriptions.tsx

@@ -1,6 +1,6 @@
-import * as q from '../../../../backend/src/Model'
+import * as q from '../../../../../../backend/src/Model'
 import React, { useEffect } from 'react'
-import { TopicViewModel } from '../../model/TopicViewModel'
+import { TopicViewModel } from '../../../../model/TopicViewModel'
 
 export function useViewModelSubscriptions(
   treeNode: q.TreeNode<TopicViewModel>,
@@ -11,6 +11,7 @@ export function useViewModelSubscriptions(
   const selectionDidChange = () => {
     const selected = treeNode.viewModel && treeNode.viewModel.isSelected()
     treeNode.viewModel && setSelected(Boolean(selected))
+
     if (selected && nodeRef && nodeRef.current) {
       nodeRef.current.focus({ preventScroll: false })
     }

app/src/components/Tree/TreeNode/index.tsx

@@ -1,14 +1,16 @@
-import * as q from '../../../../backend/src/Model'
+import * as q from '../../../../../backend/src/Model'
 import React, { useState, useRef, useEffect, useMemo, useCallback } from 'react'
 import TreeNodeSubnodes from './TreeNodeSubnodes'
 import TreeNodeTitle from './TreeNodeTitle'
-import { SettingsState } from '../../reducers/Settings'
+import { SettingsState } from '../../../reducers/Settings'
 import { Theme, withStyles } from '@material-ui/core/styles'
-import { TopicViewModel } from '../../model/TopicViewModel'
+import { TopicViewModel } from '../../../model/TopicViewModel'
-import { useViewModelSubscriptions } from './useViewModelSubscriptions'
+import { useViewModelSubscriptions } from './effects/useViewModelSubscriptions'
-const debounce = require('lodash.debounce')
+import { treeActions } from '../../../actions'
-
+import { lightBlue, teal, amber, green, deepPurple, blueGrey } from '@material-ui/core/colors'
-declare var performance: any
+import { useAnimationToIndicateTopicUpdate } from './effects/useAnimationToIndicateTopicUpdate'
+import { useDeleteKeyCallback } from './effects/useDeleteKeyCallback'
+import { useIsAllowedToAutoExpandState } from './effects/useIsAllowedToAutoExpandState'
 
 const styles = (theme: Theme) => {
   return {
@@ -21,6 +23,9 @@ const styles = (theme: Theme) => {
     node: {
       display: 'block',
       marginLeft: '10px',
+      '&:hover': {
+        backgroundColor: theme.palette.type === 'light' ? blueGrey[100] : theme.palette.primary.light,
+      },
     },
     topicSelect: {
       float: 'right' as 'right',
@@ -32,11 +37,9 @@ const styles = (theme: Theme) => {
       marginLeft: theme.spacing(1.5),
     },
     selected: {
-      backgroundColor: theme.palette.type === 'dark' ? 'rgba(170, 170, 170, 0.55)' : 'rgba(170, 170, 170, 0.55)',
+      backgroundColor: (theme.palette.type === 'light' ? blueGrey[300] : theme.palette.primary.main) + ' !important',
-    },
-    hover: {
-      backgroundColor: theme.palette.type === 'dark' ? 'rgba(100, 100, 100, 0.55)' : 'rgba(200, 200, 200, 0.55)',
     },
+    hover: {},
     title: {
       borderRadius: '4px',
       lineHeight: '1em',
@@ -49,7 +52,7 @@ const styles = (theme: Theme) => {
   }
 }
 
-interface Props {
+export interface Props {
   isRoot?: boolean
   treeNode: q.TreeNode<TopicViewModel>
   name?: string | undefined
@@ -57,44 +60,26 @@ interface Props {
   classes: any
   className?: string
   lastUpdate: number
+  actions: typeof treeActions
   selectTopicAction: (treeNode: q.TreeNode<any>) => void
   theme: Theme
   settings: SettingsState
 }
 
-function useIsAllowedToAutoExpandState(props: Props): boolean {
-  const { settings, treeNode, isRoot } = props
-  const [isAllowedToAutoExpand, setAllowAutoExpand] = useState(false)
-
-  useEffect(() => {
-    const newIsAllowedToAutoExpand = isRoot || treeNode.edgeCount() <= settings.get('autoExpandLimit')
-    if (newIsAllowedToAutoExpand !== isAllowedToAutoExpand) {
-      setAllowAutoExpand(newIsAllowedToAutoExpand)
-    }
-  }, [treeNode.edgeCount(), settings.get('autoExpandLimit')])
-
-  return isAllowedToAutoExpand
-}
-
 function TreeNodeComponent(props: Props) {
-  const { classes, className, settings, theme, treeNode, lastUpdate, name } = props
+  const { actions, classes, className, settings, theme, treeNode, lastUpdate, name } = props
-
+  const deleteTopicCallback = useDeleteKeyCallback(treeNode, actions)
   const [showUpdateAnimation, setShowUpdateAnimation] = useState(false)
   const [collapsedOverride, setCollapsedOverride] = useState<boolean | undefined>(undefined)
-  const [isHovering, setIsHovering] = useState(false)
   const [selected, setSelected] = useState(false)
   const nodeRef = useRef<HTMLDivElement>()
   const isAllowedToAutoExpand = useIsAllowedToAutoExpandState(props)
   useViewModelSubscriptions(treeNode, nodeRef, setSelected, setCollapsedOverride)
-  useAnimationToIndicateTopicUpdate(lastUpdate, setShowUpdateAnimation, showUpdateAnimation)
+  useAnimationToIndicateTopicUpdate(lastUpdate, selected, setShowUpdateAnimation, showUpdateAnimation)
 
   const isCollapsed =
     Boolean(collapsedOverride) === collapsedOverride ? Boolean(collapsedOverride) : !isAllowedToAutoExpand
 
-  const setHover = debounce((hover: boolean) => {
-    setIsHovering(hover)
-  }, 45)
-
   const toggle = useCallback(() => {
     setCollapsedOverride(!isCollapsed)
   }, [isCollapsed])
@@ -130,17 +115,11 @@ function TreeNodeComponent(props: Props) {
 
   const mouseOver = (event: React.MouseEvent) => {
     event.stopPropagation()
-    setHover(true)
     if (settings.get('selectTopicWithMouseOver') && treeNode && treeNode.message && treeNode.message.value) {
       didSelectTopic()
     }
   }
 
-  const mouseOut = (event: React.MouseEvent) => {
-    event.stopPropagation()
-    setHover(false)
-  }
-
   useEffect(() => {
     treeNode.viewModel && treeNode.viewModel.setExpanded(!isCollapsed, false)
   }, [isCollapsed])
@@ -157,6 +136,7 @@ function TreeNodeComponent(props: Props) {
           lastUpdate={treeNode.lastUpdate}
           selectTopicAction={props.selectTopicAction}
           settings={settings}
+          actions={props.actions}
         />
       )
     }
@@ -167,19 +147,19 @@ function TreeNodeComponent(props: Props) {
       ? { willChange: 'auto', translateZ: 0, animation: `${animationName} 0.5s` }
       : {}
 
-    const highlightClass = selected ? classes.selected : isHovering ? classes.hover : ''
+    const highlightClass = selected ? classes.selected : ''
     return (
       <div>
         <div
           key={treeNode.hash()}
           className={`${classes.node} ${className} ${highlightClass} ${classes.title}`}
           style={animation}
-          onMouseOver={mouseOver}
+          onMouseEnter={mouseOver}
-          onMouseOut={mouseOut}
           onFocus={didObtainFocus}
           onClick={didClickTitle}
           ref={nodeRef as any}
           tabIndex={-1}
+          onKeyDown={deleteTopicCallback}
         >
           <TreeNodeTitle
             toggleCollapsed={toggleCollapsed}
@@ -192,26 +172,7 @@ function TreeNodeComponent(props: Props) {
         {renderNodes()}
       </div>
     )
-  }, [lastUpdate, treeNode, name, isCollapsed, selected, showUpdateAnimation, isHovering])
+  }, [lastUpdate, treeNode, name, isCollapsed, selected, theme, showUpdateAnimation])
 }
 
 export default withStyles(styles, { withTheme: true })(TreeNodeComponent)
-function useAnimationToIndicateTopicUpdate(
-  lastUpdate: number,
-  setShowUpdateAnimation: React.Dispatch<React.SetStateAction<boolean>>,
-  showUpdateAnimation: boolean
-) {
-  useEffect(() => {
-    if (Date.now() - lastUpdate < 3000) {
-      setShowUpdateAnimation(true)
-    }
-  }, [lastUpdate])
-  useEffect(() => {
-    if (showUpdateAnimation) {
-      const timeout = setTimeout(() => setShowUpdateAnimation(false), 500)
-      return function cleanup() {
-        clearTimeout(timeout)
-      }
-    }
-  }, [showUpdateAnimation])
-}

app/src/components/Tree/index.tsx

@@ -1,5 +1,5 @@
 import * as q from '../../../../backend/src/Model'
-import React from 'react'
+import React, { useCallback } from 'react'
 import TreeNode from './TreeNode'
 import { AppState } from '../../reducers'
 import { bindActionCreators } from 'redux'
@@ -7,7 +7,6 @@ import { connect } from 'react-redux'
 import { SettingsState } from '../../reducers/Settings'
 import { TopicViewModel } from '../../model/TopicViewModel'
 import { treeActions } from '../../actions'
-import { useGlobalKeyEventHandler } from '../../effects/useGlobalKeyEventHandler'
 import { KeyCodes } from '../../utils/KeyCodes'
 
 const MovingAverage = require('moving-average')
@@ -30,16 +29,27 @@ interface State {
   lastUpdate: number
 }
 
-function ArrowKeyHandler(props: {
+function useArrowKeyEventHandler(actions: typeof treeActions) {
-  action: (direction: 'next' | 'previous') => any
+  return (event: React.KeyboardEvent) => {
-  leftAction: () => void
+    switch (event.keyCode) {
-  rightAction: () => void
+      case KeyCodes.arrow_down:
-}) {
+        actions.moveSelectionUpOrDownwards('next')
-  useGlobalKeyEventHandler(KeyCodes.arrow_down, () => props.action('next'), [props.action])
+        event.preventDefault()
-  useGlobalKeyEventHandler(KeyCodes.arrow_up, () => props.action('previous'), [props.action])
+        break
-  useGlobalKeyEventHandler(KeyCodes.arrow_right, props.rightAction, [props.action])
+      case KeyCodes.arrow_up:
-  useGlobalKeyEventHandler(KeyCodes.arrow_left, props.leftAction, [props.action])
+        actions.moveSelectionUpOrDownwards('previous')
-  return <div />
+        event.preventDefault()
+        break
+      case KeyCodes.arrow_left:
+        actions.moveOutward()
+        event.preventDefault()
+        break
+      case KeyCodes.arrow_right:
+        actions.moveInward()
+        event.preventDefault()
+        break
+    }
+  }
 }
 
 class TreeComponent extends React.PureComponent<Props, State> {
@@ -52,6 +62,7 @@ class TreeComponent extends React.PureComponent<Props, State> {
     this.state = { lastUpdate: 0 }
   }
 
+  private keyEventHandler = useArrowKeyEventHandler(this.props.actions)
   private performanceCallback = (ms: number) => {
     average.push(Date.now(), ms)
   }
@@ -124,16 +135,12 @@ class TreeComponent extends React.PureComponent<Props, State> {
       overflowX: 'hidden',
       height: '100%',
       width: '100%',
+      outline: '24px black !important',
       paddingBottom: '16px', // avoid conflict with chart panel Resizer
     }
 
     return (
-      <div style={style}>
+      <div style={style} tabIndex={0} onKeyDown={this.keyEventHandler}>
-        <ArrowKeyHandler
-          action={this.props.actions.moveSelectionUpOrDownwards}
-          leftAction={this.props.actions.moveOutward}
-          rightAction={this.props.actions.moveInward}
-        />
         <TreeNode
           key={tree.hash()}
           isRoot={true}
@@ -142,6 +149,7 @@ class TreeComponent extends React.PureComponent<Props, State> {
           collapsed={false}
           settings={this.props.settings}
           lastUpdate={tree.lastUpdate}
+          actions={this.props.actions}
           selectTopicAction={this.props.actions.selectTopic}
         />
       </div>

app/src/model/TopicViewModel.ts

@@ -4,8 +4,8 @@ import { EventDispatcher } from '../../../events'
 export class TopicViewModel implements Destroyable {
   private selected: boolean
   private expanded: boolean
-  public selectionChange = new EventDispatcher<void, TopicViewModel>()
+  public selectionChange = new EventDispatcher<void>()
-  public expandedChange = new EventDispatcher<void, TopicViewModel>()
+  public expandedChange = new EventDispatcher<void>()
 
   public constructor() {
     this.selected = false

app/src/reducers/Global.ts

@@ -44,7 +44,6 @@ export const globalState: Reducer<Record<GlobalStateInterface>, GlobalAction> =
   action
 ): GlobalState => {
   trackEvent(action.type)
-  console.log(action.type)
 
   switch (action.type) {
     case ActionTypes.showUpdateNotification:

backend/src/DataSource/DataSourceState.ts

@@ -7,7 +7,7 @@ export interface DataSourceState {
 }
 
 export class DataSourceStateMachine {
-  public onUpdate = new EventDispatcher<DataSourceState, DataSourceStateMachine>()
+  public onUpdate = new EventDispatcher<DataSourceState>()
   private state: DataSourceState = {
     error: undefined,
     connected: false,

backend/src/Model/Tree.ts

@@ -12,7 +12,7 @@ export class Tree<ViewModel extends Destroyable> extends TreeNode<ViewModel> {
   public isTree = true
   private cachedHash = `${Math.random()}`
   private unmergedMessages: ChangeBuffer = new ChangeBuffer()
-  public didReceive = new EventDispatcher<void, Tree<ViewModel>>()
+  public didReceive = new EventDispatcher<void>()
 
   constructor() {
     super(undefined, undefined)

backend/src/Model/TreeNode.ts

@@ -13,9 +13,10 @@ export class TreeNode<ViewModel extends Destroyable> {
   public collapsed = false
   public messages: number = 0
   public lastUpdate: number = Date.now()
-  public onMerge = new EventDispatcher<void, TreeNode<ViewModel>>()
+  public onMerge = new EventDispatcher<void>()
-  public onEdgesChange = new EventDispatcher<void, TreeNode<ViewModel>>()
+  public onEdgesChange = new EventDispatcher<void>()
-  public onMessage = new EventDispatcher<Message, TreeNode<ViewModel>>()
+  public onMessage = new EventDispatcher<Message>()
+  public onDestroy = new EventDispatcher<TreeNode<ViewModel>>()
   public isTree = false
 
   private cachedPath?: string
@@ -65,7 +66,11 @@ export class TreeNode<ViewModel extends Destroyable> {
     if (!previous || !this.sourceEdge) {
       return
     }
+    this.lastUpdate = Date.now()
     previous.removeEdge(this.sourceEdge)
+    if (!this.isTree) {
+      this.destroy()
+    }
   }
 
   private findChild(edges: Array<string>): TreeNode<ViewModel> | undefined {
@@ -101,6 +106,9 @@ export class TreeNode<ViewModel extends Destroyable> {
   }
 
   public destroy() {
+    this.onDestroy.dispatch(this)
+    this.onDestroy.removeAllListeners()
+
     for (const edge of this.edgeArray) {
       edge.target.destroy()
     }
@@ -158,6 +166,8 @@ export class TreeNode<ViewModel extends Destroyable> {
     this.edgeArray.push(edge)
     edge.source = this
 
+    edge.target && edge.target.removeFromTreeIfEmpty()
+
     if (emitUpdate) {
       this.onEdgesChange.dispatch()
     }
@@ -175,8 +185,12 @@ export class TreeNode<ViewModel extends Destroyable> {
   public removeEdge(edge: Edge<any>) {
     delete this.edges[edge.name]
     this.edgeArray = Object.values(this.edges)
-    this.onMerge.dispatch()
 
+    this.removeFromTreeIfEmpty()
+    this.onMerge.dispatch()
+  }
+
+  public removeFromTreeIfEmpty() {
     if (this.isTopicEmptyLeaf()) {
       this.removeFromParent()
     }
@@ -189,10 +203,7 @@ export class TreeNode<ViewModel extends Destroyable> {
       this.mqttMessage = node.mqttMessage
     }
 
-    if (this.isTopicEmptyLeaf()) {
+    this.removeFromTreeIfEmpty()
-      this.removeFromParent()
-    }
-
     this.mergeEdges(node)
     this.onMerge.dispatch()
   }

backend/src/Model/spec/EventDispatcher.spec.ts

@@ -4,7 +4,7 @@ import 'mocha'
 
 describe('EventDispatcher', async () => {
   it('should dispatch', async function() {
-    const dispatcher = new EventDispatcher<string, string>()
+    const dispatcher = new EventDispatcher<string>()
     this.timeout(300)
 
     setTimeout(() => dispatcher.dispatch('hello'), 5)
@@ -18,7 +18,7 @@ describe('EventDispatcher', async () => {
   })
 
   it('should unsubscribe', async function() {
-    const dispatcher = new EventDispatcher<string, string>()
+    const dispatcher = new EventDispatcher<string>()
     this.timeout(300)
     let callbackCounter = 0
     const callback = (msg: any) => {

backend/src/index.ts

@@ -45,7 +45,6 @@ export class ConnectionManager {
       if (buffer.length > 20000) {
         buffer = buffer.slice(0, 20000)
       }
-
       backendEvents.emit(messageEvent, {
         topic,
         payload: Base64Message.fromBuffer(buffer),

events/EventDispatcher.ts

@@ -5,7 +5,7 @@ interface CallbackStore {
   callback: any
 }
 
-export class EventDispatcher<Message, Dispatcher> {
+export class EventDispatcher<Message> {
   private emitter = new EventEmitter()
   private callbacks: Array<CallbackStore> = []
 

src/MenuTemplate.ts

@@ -10,7 +10,7 @@ const applicationMenu: MenuItemConstructorOptions = {
       click: () => {
         openAboutWindow({
           icon_path: path.join(__dirname, '..', '..', 'icon.png'),
-          license: 'AGPL-3.0',
+          license: 'CC-BY-ND-4.0',
           homepage: 'https://thomasnordquist.github.io/MQTT-Explorer/',
           bug_report_url: 'https://github.com/thomasnordquist/MQTT-Explorer/issues',
           description: 'Author: Thomas Nordquist',