如何使用$ Q摆脱在angularJS一个$ broastcast一个承诺 [英] How to use $q to get a promise from a $broastcast in angularJS

问题描述

现在我的控制器code是这样的：

Right now my controller code looks like this:

$scope.spAPI.load(id).then(function(result){
  var deferred = $q.defer();
  if(result !== undefined){
    deferred.resolve($rootScope.$broadcast("onSpLoaded", result));
  }
  return deferred.promise;
}).then(function(success){

      $scope.modalInstance = $modal.open({ ... });


});

我想追广播节目进行处理，以开放的模式实例。有没有办法做到这一点？

I want the modal instance to be opened AFTER the broadcasts are processed. Is there a way to do this?

更新：我想这个问题倒退。我的意思是模态实例后做广播，反正不要介意。

Update: I was thinking about this problem backwards. I meant to do the broadcast after the modal instance, anyway, nevermind.

PS：我确实有与modalinstance.opened回调的问题，虽然，我不得不砍围绕自己的路。我仍在苦苦正确使用$ Q，我code已经越来越混乱。

PS: I did have problems with the modalinstance.opened callback though, I had to hack my way around it. I am still struggling to use $q correctly, my code has been getting messier.

推荐答案

您控制器code看起来不错，应该按预期工作，你就不需要延迟对象在第一个则（）：

Your controller code looks fine, it should work as expected, you just don't need the deferred object in your first then():

$scope.spAPI.load(id).then(function(result){

  if(result !== undefined){
    $rootScope.$broadcast("onSpLoaded", result);
  }

}).then(function(success){

  $scope.modalInstance = $modal.open({ ... });


});

在这里的原因是因为 $广播（）是同步操作，所有的事件处理程序将被调用时 $广播（）的回报;并在第二功能则（）只会在函数后，被称为第一个则（）的回报，所以 $ modal.open（）将所有事件处理程序后调用。

The reason here is because $broadcast() is synchronous operation, all the event handlers will have been called when $broadcast() returns; and the function in 2nd then() will only be called after the function in the first then() returns, so $modal.open() will be called after all event handlers.

<大骨节病> 演示

您知道 $ scope.modalInstance.opened 是当模式被所示，将得到解决，所以你可以尝试以下操作来实现你想要的承诺：

You know that $scope.modalInstance.opened is a promise which will be resolved when the modal gets shown, so you can try the following to achieve what you want:

$scope.spAPI.load(id).then(function(result){
    $scope.modalInstance = $modal.open({ ... });

    $scope.modalInstance.opened.then(function() {
        $rootScope.$broadcast("onSpLoaded", result));
    });
});

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