| // Copyright (c) 2013, 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. |
| |
| /// Code from declaration/events.js |
| part of polymer; |
| |
| /// An extension of [polymer_expressions.PolymerExpressions] that adds support |
| /// for binding events using `on-eventName` using [PolymerEventBindings]. |
| // TODO(jmesserly): the JS layering is a bit odd, with polymer-dev implementing |
| // events and polymer-expressions implementing everything else. I don't think |
| // this separation is right in the long term, so we're using the same class name |
| // until we can sort it out. |
| class PolymerExpressions extends BindingDelegate with PolymerEventBindings { |
| |
| /// A wrapper around polymer_expressions used to implement forwarding. |
| /// Ideally we would inherit from it, but mixins can't be applied to a type |
| /// that forwards to a superclass with a constructor that has optional or |
| /// named arguments. |
| final BindingDelegate _delegate; |
| |
| PolymerExpressions({Map<String, Object> globals}) |
| : _delegate = new polymer_expressions.PolymerExpressions( |
| globals: globals); |
| |
| prepareBinding(String path, name, node) { |
| if (_hasEventPrefix(name)) { |
| return prepareEventBinding(path, name, node); |
| } |
| return _delegate.prepareBinding(path, name, node); |
| } |
| |
| prepareInstanceModel(Element template) => |
| _delegate.prepareInstanceModel(template); |
| |
| prepareInstancePositionChanged(Element template) => |
| _delegate.prepareInstancePositionChanged(template); |
| } |
| |
| /// A mixin for a [BindingDelegate] to add Polymer event support. |
| /// This is included in [PolymerExpressions]. |
| abstract class PolymerEventBindings { |
| /// Finds the event controller for this node. |
| Element findController(Node node) { |
| while (node.parentNode != null) { |
| if (node is Polymer && node.eventController != null) { |
| return node.eventController; |
| } |
| node = node.parentNode; |
| } |
| return node is ShadowRoot ? node.host : null; |
| } |
| |
| EventListener getEventHandler(controller, target, String method) => (e) { |
| if (controller == null || controller is! Polymer) { |
| controller = findController(target); |
| } |
| |
| if (controller is Polymer) { |
| var detail = null; |
| if (e is CustomEvent) { |
| detail = e.detail; |
| // TODO(sigmund): this shouldn't be necessary. See issue 19315. |
| if (detail == null) { |
| detail = new JsObject.fromBrowserObject(e)['detail']; |
| } |
| } |
| var args = [e, detail, e.currentTarget]; |
| controller.dispatchMethod(controller, method, args); |
| } else { |
| throw new StateError('controller $controller is not a ' |
| 'Dart polymer-element.'); |
| } |
| }; |
| |
| prepareEventBinding(String path, String name, Node node) { |
| if (!_hasEventPrefix(name)) return null; |
| |
| var eventType = _removeEventPrefix(name); |
| var translated = _eventTranslations[eventType]; |
| eventType = translated != null ? translated : eventType; |
| |
| return (model, node, oneTime) { |
| var handler = getEventHandler(null, node, path); |
| var sub = node.on[eventType].listen(handler); |
| |
| if (oneTime) return null; |
| return new _EventBindable(sub, path); |
| }; |
| } |
| } |
| |
| |
| class _EventBindable extends Bindable { |
| StreamSubscription _sub; |
| final String _path; |
| |
| _EventBindable(this._sub, this._path); |
| |
| // TODO(rafaelw): This is really pointless work. Aside from the cost |
| // of these allocations, NodeBind is going to setAttribute back to its |
| // current value. Fixing this would mean changing the TemplateBinding |
| // binding delegate API. |
| get value => '{{ $_path }}'; |
| |
| open(callback) => value; |
| |
| void close() { |
| if (_sub != null) { |
| _sub.cancel(); |
| _sub = null; |
| } |
| } |
| } |
| |
| |
| /// Attribute prefix used for declarative event handlers. |
| const _EVENT_PREFIX = 'on-'; |
| |
| /// Whether an attribute declares an event. |
| bool _hasEventPrefix(String attr) => attr.startsWith(_EVENT_PREFIX); |
| |
| String _removeEventPrefix(String name) => name.substring(_EVENT_PREFIX.length); |
| |
| // Dart note: polymer.js calls this mixedCaseEventTypes. But we have additional |
| // things that need translation due to renames. |
| final _eventTranslations = const { |
| 'domfocusout': 'DOMFocusOut', |
| 'domfocusin': 'DOMFocusIn', |
| 'dommousescroll': 'DOMMouseScroll', |
| |
| // Dart note: handle Dart-specific event names. |
| 'animationend': 'webkitAnimationEnd', |
| 'animationiteration': 'webkitAnimationIteration', |
| 'animationstart': 'webkitAnimationStart', |
| 'doubleclick': 'dblclick', |
| 'fullscreenchange': 'webkitfullscreenchange', |
| 'fullscreenerror': 'webkitfullscreenerror', |
| 'keyadded': 'webkitkeyadded', |
| 'keyerror': 'webkitkeyerror', |
| 'keymessage': 'webkitkeymessage', |
| 'needkey': 'webkitneedkey', |
| 'speechchange': 'webkitSpeechChange', |
| }; |
| |
| final _reverseEventTranslations = () { |
| final map = new Map<String, String>(); |
| _eventTranslations.forEach((onName, eventType) { |
| map[eventType] = onName; |
| }); |
| return map; |
| }(); |
| |
| // Dart note: we need this function because we have additional renames JS does |
| // not have. The JS renames are simply case differences, whereas we have ones |
| // like doubleclick -> dblclick and stripping the webkit prefix. |
| String _eventNameFromType(String eventType) { |
| final result = _reverseEventTranslations[eventType]; |
| return result != null ? result : eventType; |
| } |