flutter/examples/raw/hello_world.dart
Adam Barth 83805e2a9e Plumb input events into SkyView
Clients can now register a callback that gets called whenever we have an event
for the view. We'll need to update the Event class at some point, but this is a
start.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1129333005
2015-05-19 16:50:28 -07:00

43 lines
1013 B
Dart

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import "dart:math";
import 'dart:sky';
Picture draw(int a, int r, int g, int b) {
double width = view.width;
double height = view.height;
PictureRecorder recorder = new PictureRecorder(width, height);
double radius = min(width, height) * 0.45;
Paint paint = new Paint()..setARGB(a, r, g, b);
recorder.drawCircle(width / 2, height / 2, radius, paint);
return recorder.endRecording();
}
bool handleEvent(Event event) {
if (event.type == "pointerdown") {
view.picture = draw(255, 0, 0, 255);
view.schedulePaint();
return true;
}
if (event.type == "pointerup") {
view.picture = draw(255, 0, 255, 0);
view.schedulePaint();
return true;
}
return false;
}
void main() {
print("Hello, world");
view.picture = draw(255, 0, 255, 0);
view.schedulePaint();
view.setEventCallback(handleEvent);
}