Merge pull request #118 from martinRenou/fix_multicanvas_events

MultiCanvas: fix events

Author: martinRenou

ipycanvas/canvas.py

@@ -630,6 +630,9 @@ def __init__(self, n_canvases=3, *args, **kwargs):
         """Constructor."""
         super(MultiCanvas, self).__init__(*args, _canvases=[Canvas() for _ in range(n_canvases)], **kwargs)
 
+        # The latest canvas receives events (interaction layer)
+        self.on_msg(self._canvases[-1]._handle_frontend_event)
+
     def __getitem__(self, key):
         """Access one of the Canvas instances."""
         return self._canvases[key]

src/widget.ts

@@ -414,7 +414,7 @@ class CanvasView extends DOMWidgetView {
   el: HTMLCanvasElement;
   ctx: CanvasRenderingContext2D;
 
-  model: CanvasModel;
+  model: CanvasModel | MultiCanvasModel;
 }
 
 
@@ -525,36 +525,6 @@ class MultiCanvasModel extends DOMWidgetModel {
 
 
 export
-class MultiCanvasView extends DOMWidgetView {
-  render() {
-    this.ctx = getContext(this.el);
-
-    this.resizeCanvas();
-    this.model.on_some_change(['width', 'height'], this.resizeCanvas, this);
-
-    this.updateCanvas();
-  }
-
-  clear() {
-    this.ctx.clearRect(0, 0, this.el.width, this.el.height);
-  }
-
-  updateCanvas() {
-    this.clear();
-    this.ctx.drawImage(this.model.canvas, 0, 0);
-  }
-
-  private resizeCanvas() {
-    this.el.setAttribute('width', this.model.get('width'));
-    this.el.setAttribute('height', this.model.get('height'));
-  }
-
-  get tagName(): string {
-    return 'canvas';
-  }
-
-  el: HTMLCanvasElement;
-  ctx: CanvasRenderingContext2D;
-
+class MultiCanvasView extends CanvasView {
   model: MultiCanvasModel;
 }