Merge pull request #1365 from baleeds/feature/detect-parent-resize

feature: Detect parent resize

3 files changed, 31 insertions, 17 deletions

diff --git a/README.md b/README.md
index 7bcb52a..3f8abf8 100644
--- a/README.md
+++ b/README.md
@@ -91,7 +91,7 @@ noVNC uses many modern web technologies so a formal requirement list is
 not available. However these are the minimum versions we are currently
 aware of:
 
-* Chrome 49, Firefox 44, Safari 11, Opera 36, Edge 79
+* Chrome 64, Firefox 79, Safari 13.4, Opera 51, Edge 79
 
 
 ### Server Requirements
diff --git a/core/rfb.js b/core/rfb.js
index 228aeca..ea3bf58 100644
--- a/core/rfb.js
+++ b/core/rfb.js
@@ -134,6 +134,7 @@ export default class RFB extends EventTargetMixin {
         this._flushing = false;         // Display flushing state
         this._keyboard = null;          // Keyboard input handler object
         this._gestures = null;          // Gesture input handler object
+        this._resizeObserver = null;    // Resize observer object
 
         // Timers
         this._disconnTimer = null;      // disconnection timer
@@ -171,7 +172,7 @@ export default class RFB extends EventTargetMixin {
         // Bound event handlers
         this._eventHandlers = {
             focusCanvas: this._focusCanvas.bind(this),
-            windowResize: this._windowResize.bind(this),
+            handleResize: this._handleResize.bind(this),
             handleMouse: this._handleMouse.bind(this),
             handleWheel: this._handleWheel.bind(this),
             handleGesture: this._handleGesture.bind(this),
@@ -239,6 +240,8 @@ export default class RFB extends EventTargetMixin {
         this._sock.on('message', this._handleMessage.bind(this));
         this._sock.on('error', this._socketError.bind(this));
 
+        this._resizeObserver = new ResizeObserver(this._eventHandlers.handleResize);
+
         // All prepared, kick off the connection
         this._updateConnectionState('connecting');
 
@@ -488,9 +491,8 @@ export default class RFB extends EventTargetMixin {
         this._cursor.attach(this._canvas);
         this._refreshCursor();
 
-        // Monitor size changes of the screen
-        // FIXME: Use ResizeObserver, or hidden overflow
-        window.addEventListener('resize', this._eventHandlers.windowResize);
+        // Monitor size changes of the screen element
+        this._resizeObserver.observe(this._screen);
 
         // Always grab focus on some kind of click event
         this._canvas.addEventListener("mousedown", this._eventHandlers.focusCanvas);
@@ -531,7 +533,7 @@ export default class RFB extends EventTargetMixin {
         this._canvas.removeEventListener('contextmenu', this._eventHandlers.handleMouse);
         this._canvas.removeEventListener("mousedown", this._eventHandlers.focusCanvas);
         this._canvas.removeEventListener("touchstart", this._eventHandlers.focusCanvas);
-        window.removeEventListener('resize', this._eventHandlers.windowResize);
+        this._resizeObserver.disconnect();
         this._keyboard.ungrab();
         this._gestures.detach();
         this._sock.close();
@@ -617,7 +619,7 @@ export default class RFB extends EventTargetMixin {
             { detail: { name: this._fbName } }));
     }
 
-    _windowResize(event) {
+    _handleResize() {
         // If the window resized then our screen element might have
         // as well. Update the viewport dimensions.
         window.requestAnimationFrame(() => {
diff --git a/tests/test.rfb.js b/tests/test.rfb.js
index 404f7db..5f50581 100644
--- a/tests/test.rfb.js
+++ b/tests/test.rfb.js
@@ -71,6 +71,18 @@ function deflateWithSize(data) {
 describe('Remote Frame Buffer Protocol Client', function () {
     let clock;
     let raf;
+    let fakeResizeObserver = null;
+    const realObserver = window.ResizeObserver;
+
+    class FakeResizeObserver {
+        constructor(handler) {
+            this.fire = handler;
+            fakeResizeObserver = this;
+        }
+        disconnect() {}
+        observe(target, options) {}
+        unobserve(target) {}
+    }
 
     before(FakeWebSocket.replace);
     after(FakeWebSocket.restore);
@@ -80,6 +92,9 @@ describe('Remote Frame Buffer Protocol Client', function () {
         // sinon doesn't support this yet
         raf = window.requestAnimationFrame;
         window.requestAnimationFrame = setTimeout;
+        // We must do this in a 'before' since it needs to be set before
+        // the RFB constructor, which runs in beforeEach further down
+        window.ResizeObserver = FakeResizeObserver;
         // Use a single set of buffers instead of reallocating to
         // speed up tests
         const sock = new Websock();
@@ -100,6 +115,7 @@ describe('Remote Frame Buffer Protocol Client', function () {
         delete Websock.prototype.toString;
         this.clock.restore();
         window.requestAnimationFrame = raf;
+        window.ResizeObserver = realObserver;
     });
 
     let container;
@@ -470,6 +486,7 @@ describe('Remote Frame Buffer Protocol Client', function () {
 
     describe('Clipping', function () {
         let client;
+
         beforeEach(function () {
             client = makeRFB();
             container.style.width = '70px';
@@ -495,8 +512,7 @@ describe('Remote Frame Buffer Protocol Client', function () {
 
             container.style.width = '40px';
             container.style.height = '50px';
-            const event = new UIEvent('resize');
-            window.dispatchEvent(event);
+            fakeResizeObserver.fire();
             clock.tick();
 
             expect(client._display.viewportChangeSize).to.have.been.calledOnce;
@@ -692,8 +708,7 @@ describe('Remote Frame Buffer Protocol Client', function () {
 
             container.style.width = '40px';
             container.style.height = '50px';
-            const event = new UIEvent('resize');
-            window.dispatchEvent(event);
+            fakeResizeObserver.fire();
             clock.tick();
 
             expect(client._display.autoscale).to.have.been.calledOnce;
@@ -782,8 +797,7 @@ describe('Remote Frame Buffer Protocol Client', function () {
         it('should request a resize when the container resizes', function () {
             container.style.width = '40px';
             container.style.height = '50px';
-            const event = new UIEvent('resize');
-            window.dispatchEvent(event);
+            fakeResizeObserver.fire();
             clock.tick(1000);
 
             expect(RFB.messages.setDesktopSize).to.have.been.calledOnce;
@@ -793,16 +807,14 @@ describe('Remote Frame Buffer Protocol Client', function () {
         it('should not resize until the container size is stable', function () {
             container.style.width = '20px';
             container.style.height = '30px';
-            const event1 = new UIEvent('resize');
-            window.dispatchEvent(event1);
+            fakeResizeObserver.fire();
             clock.tick(400);
 
             expect(RFB.messages.setDesktopSize).to.not.have.been.called;
 
             container.style.width = '40px';
             container.style.height = '50px';
-            const event2 = new UIEvent('resize');
-            window.dispatchEvent(event2);
+            fakeResizeObserver.fire();
             clock.tick(400);
 
             expect(RFB.messages.setDesktopSize).to.not.have.been.called;