workaround: invalidate root editor directly if it is found

Views/Cursor.xaml.fs

@@ -35,7 +35,6 @@ type Cursor() as this =
  let mutable cursor_fb = AllocateFramebuffer (20.0) (20.0) 1.0
  let mutable cursor_fb_vm = CursorViewModel(Some -1)
  let mutable cursor_fb_s = 1.0
- let mutable render_queued = false
 
  let ensure_fb() =
  let s = this.GetVisualRoot().RenderScaling
@@ -91,9 +90,7 @@ type Cursor() as this =
  (* reconfigure the cursor *)
  showCursor true
  cursorTimerRun blinkon this.ViewModel.blinkwait
- if not render_queued then
- render_queued <- true
- this.InvalidateVisual()
+ this.InvalidateVisual()
 
  let setCursorAnimation() =
  let transitions = Transitions()
@@ -181,5 +178,3 @@ type Cursor() as this =
  let region = Rect(0.0, 0.0, cellw p, this.Height)
  ctx.FillRectangle(SolidColorBrush(this.ViewModel.bg), region)
 
- render_queued <- false
-

Views/Editor.xaml.fs

@@ -35,6 +35,7 @@ type Editor() as this =
 
  static let ViewModelProperty = AvaloniaProperty.Register<Editor, EditorViewModel>("ViewModel")
  static let GridIdProperty = AvaloniaProperty.Register<Editor, int>("GridId")
+ static let RenderTickProperty = AvaloniaProperty.Register<Editor, int>("RenderTick")
 
  let mutable grid_fb: RenderTargetBitmap = null
  let mutable grid_scale: float = 1.0
@@ -181,6 +182,10 @@ type Editor() as this =
  Model.OnGridReady(vm :> IGridUI)
  ignore <| Dispatcher.UIThread.InvokeAsync(this.Focus))
 
+ this.GetObservable(RenderTickProperty).Subscribe(fun id -> 
+ trace grid_vm "render tick %d" id
+ this.InvalidateVisual())
+
  vm.ChildGrids.CollectionChanged.Subscribe(fun changes ->
  match changes.Action with
  | NotifyCollectionChangedAction.Add ->
@@ -318,4 +323,8 @@ type Editor() as this =
  with get () = this.GetValue(GridIdProperty)
  and set (v: int) = this.SetValue(GridIdProperty, v)
 
+ member this.RenderTick
+ with get() = this.GetValue(RenderTickProperty)
+ and set(v) = this.SetValue(RenderTickProperty, v)
+
  static member GetGridIdProp() = GridIdProperty

Views/MainWindow.xaml

@@ -43,7 +43,7 @@
  Opacity = "{Binding BackgroundImageOpacity}"
  />
 
- <fvim:Editor Grid.Row="1" Grid.Column="1" DataContext="{Binding MainGrid}" GridId="{Binding GridId}" />
+ <fvim:Editor Grid.Row="1" Grid.Column="1" DataContext="{Binding MainGrid}" GridId="{Binding GridId}" Name="RootEditor" />
  <Panel Name="LeftBorder" Grid.Row="0" Grid.RowSpan="3" Grid.Column="0" IsVisible="{Binding CustomTitleBar}" Background="{Binding NormalBackground}" />
  <Panel Name="RightBorder" Grid.Row="0" Grid.RowSpan="3" Grid.Column="2" IsVisible="{Binding CustomTitleBar}" Background="{Binding NormalBackground}" />
  <Panel Name="BottomBorder" Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="3" IsVisible="{Binding CustomTitleBar}" Background="{Binding NormalBackground}" />

Views/MainWindow.xaml.fs

@@ -15,6 +15,7 @@ open Avalonia.ReactiveUI
 open System.Runtime.InteropServices
 open Avalonia.Rendering
 open Avalonia.Interactivity
+open Avalonia.VisualTree
 
 #nowarn "0025"
 
@@ -120,12 +121,12 @@ type MainWindow() as this =
  DragDrop.SetAllowDrop(this, true)
  configBackground()
 
- let flushop = 
- if RuntimeInformation.IsOSPlatform(OSPlatform.Linux) then
-  fun () -> 
-  let editor: Avalonia.VisualTree.IVisual = this.GetEditor()
-  editor.InvalidateVisual()
- else this.InvalidateVisual
+ let flushop () = 
+ let editor: IControl = this.GetEditor()
+ if editor <> null then
+ editor.InvalidateVisual()
+ else
+  this.InvalidateVisual()
 
  this.Watch [
  this.Closing.Subscribe (fun e -> Model.OnTerminating e)
@@ -185,7 +186,7 @@ type MainWindow() as this =
  m_bottom_border <- this.FindControl<Panel>("BottomBorder")
 
  member this.GetEditor() =
-  this.LogicalChildren.[0] :?> Avalonia.VisualTree.IVisual
+ this.FindControl("RootEditor")
 
  override this.OnDataContextChanged _ =
  let ctx = this.DataContext :?> MainWindowViewModel