JavaScript中的Dart事件 [英] Dart events in JavaScript

问题描述

我有这个代码这里，我将其转换为Dart。问题是回调。

I have this code here, which I am converting to Dart. The problem is with the callbacks.

function stop(e) {
    var node = e.target.getContainer();
    node[SMap.LAYER_MARKER].style.cursor = "";
    var coords = e.target.getCoords();
    alert("Cílová pozice: " + coords.toWGS84(2).reverse().join(" "));
}

var signals = mapa.getSignals();
signals.addListener(window, "marker-drag-stop", stop);

我在Dart中的代码

  var signals = mapa.callMethod('getSignals', []);
  signals.callMethod('addListener', [context, 'marker-drag-stop', stop]);
}


stop(MouseEvent event) {
  var target = event.target.callMethod('getContainer',[]);// problem
  context.callMethod('alert', ['texttext']); 
}

stop回调被正确调用，但我不知道该怎么办与 var node = e.target.getContainer（）; 行。

The stop callback is properly called, but I don't know what to do with var node = e.target.getContainer(); line. The e.target return something, but what next.

问题： mapa.callMethod（'addLayer'，[layer]）。callMethod （'enable'，[]）; 语法，只有一种可能的方式来调用javascript方法。我发现它有点麻烦： - /

Side question: is mapa.callMethod('addLayer', [layer]).callMethod('enable', []); syntax, only one posible way to call javascript methods. I find it little bit cumbersome:-/

这整个js-interop东西是有点凌乱。我无法由我自己解决它，需要在每一步后再次询问。我希望当我覆盖所有interop用例，我将能够，只是使用Dart并忘记JS。

This whole js-interop thingy is kind of messy. I'm unable to resolve it by my own and need to ask again after each step. I hope when I will cover all interop use cases, I will be able, just to use Dart and forget about JS.

推荐答案

我假设这应该做的诀窍：

I assume this should do the trick:

var target = new js.JsObject.fromBrowserObject(e)['target']
  .callMethod('getContainer', []);

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