adding game_of_life sample

dart/samples/webcomponents/game_of_life/components/components.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+typedef WebComponent ComponentConstructorThunk();
+
+class Cell extends DivElementImpl implements WebComponent, Hashable {

[Siggi Cherem (dart-lang), 2012/09/05 20:53:03]

+dartdoc in classes and importnat methods (e.g. step)

[samhop, 2012/09/07 21:41:30]

Done.

+  Collection<Cell> neighbors;
+  ShadowRoot _root;
+  CellCoordinator coordinator;
+  bool aliveThisStep;
+  bool aliveNextStep;
+
+  bool get alive => this.classes.contains('alive');
+
+  void step() {
+    var numAlive = neighbors.filter((n) => n.aliveThisStep).length;
+    // We could compress this into one line, but it's clearer this way.
+    aliveNextStep = false;
+    if (aliveThisStep) {
+      if (numAlive == 2 || numAlive == 3) {
+        aliveNextStep = true;
+      }
+    } else {
+      if (numAlive == 3) {
+        aliveNextStep = true;
+      }
+    }
+  }
+
+  void resolve() {
+    if (aliveNextStep) {
+      classes.add('alive');
+    } else {
+      classes.remove('alive');
+    }
+    aliveThisStep = aliveNextStep;
+  }
+
+  static ComponentConstructorThunk _$constr;

[Siggi Cherem (dart-lang), 2012/09/05 20:53:03]

it might be worth to indicate (possibly move to the end of the class) this magic
glue code that is supposed to be autogenerated.

[samhop, 2012/09/07 21:41:30]

Done.

+  factory Cell.component() {
+    if(_$constr == null) {
+      _$constr = () => new Cell._internal();
+    }
+    var t1 = new DivElement();
+    t1.attributes['is'] = 'x-cell';
+    rewirePrototypeChain(t1, _$constr, 'Cell');
+    return t1;
+  }
+
+  factory Cell() {
+    return manager.expandHtml('<div is="x-cell"></div>');
+  }
+
+  Cell._internal();
+
+  void created(ShadowRoot root) {
+    _root = root;
+    neighbors = <Cell>[];
+    this.classes.add('cell');
+  }
+
+  void inserted() { }
+
+  void bound() {
+    on.click.add((event) {
+      classes.toggle('alive');
+      aliveThisStep = !aliveThisStep;
+    });
+
+    coordinator.on.step.add(step);
+    coordinator.on.resolve.add(resolve);
+
+    // find neighbors
+    var parsedCoordinates = this.id.substring(1).split('y');
+    var x = Math.parseInt(parsedCoordinates[0]);
+    var y = Math.parseInt(parsedCoordinates[1]);
+    for (int dx = -1; dx <= 1; dx++) {
+      for (int dy = -1; dy <= 1; dy++) {
+        if (inGrid(x + dx, y + dy) && !(dx == 0 && dy == 0)) {
+          var neighbor = query('#x${x + dx}y${y + dy}');
+          neighbors.add(neighbor);
+        }
+      }
+    }
+  }
+
+  static bool inGrid(x, y) =>
+    (x >=0 && y >=0 && x < GAME_SIZE && y < GAME_SIZE);
+
+  void attributeChanged(String name, String oldValue, String newValue) { }
+
+  void removed() { }
+
+}
+
+class ControlPanel extends DivElementImpl implements WebComponent {
+  ShadowRoot _root;
+  CellCoordinator coordinator;
+
+  static ComponentConstructorThunk _$constr;
+  factory ControlPanel.component() {
+    if(_$constr == null) {
+      _$constr = () => new ControlPanel._internal();
+    }
+    var t1 = new DivElement();
+    t1.attributes['is'] = 'x-control-panel';
+    rewirePrototypeChain(t1, _$constr, 'ControlPanel');
+    return t1;
+  }
+
+  factory ControlPanel() {
+    return manager.expandHtml('<div is="x-control-panel"></div>');
+  }
+
+  ControlPanel._internal();
+
+  void created(ShadowRoot root) {
+    _root = root;
+  }
+
+  void inserted() { 
+    _root.query('#start').on.click.add((e) => COORDINATOR.run());
+    _root.query('#stop').on.click.add((e) => COORDINATOR.stop());
+    _root.query('#step').on.click.add((e) => COORDINATOR.step());
+  }
+
+  void attributeChanged(String name, String oldValue, String newValue) { }
+
+  void removed() { }
+}