Question

鉴于此指令：

writing.directive('writingFocus', function($timeout){
  return {
    restrict: 'AC',
    scope: false,
    link: function(scope, element, attrs){
      scope.$watch(attrs.writingFocus, function(value){
        console.log('Value from directive', value);
        if(value === true){
          $timeout(function(){
            element[0].focus();
            scope[attrs.writingFocus] = false; // Not in controller's scope!!!
          });
        }
      });
    }
  }
});

以这种方式使用：

<input type="text" ng-model="selectedNote.title" writing-focus="justOpened">

指令中对justOpened（attrs.writingFocus）所做的更改未应用于我正在观看它的控制器范围内：

$scope.$watch('justOpened', function(val, old){console.log('value from controller', val, old)})

即使使用具有双向绑定的隔离范围也不起作用：

writing.directive('writingFocus', function($timeout){
  return {
    restrict: 'AC',
    scope: {
        writingFocus: '='
    },
    link: function(scope, element, attrs){
      scope.$watch('writingFocus', function(value){
        console.log('Value from directive', value);
        if(value === true){
          $timeout(function(){
            element[0].focus();
            scope.writingFocus = false; // Not in controller's scope!!!
          });
        }
      });
    }
  }
});

它第一次运行，从控制器获取值，但看起来没有绑定。

控制器：

writing.controller('NotesCtrl', function($scope){
  $scope.notes = db.findAll();
  $scope.$watch('justOpened', function(val, old){console.log('value from controller', val, old)})

  $scope.add = function(){
    var note = {title: 'new note'};
    note.id = db.insert(note);
    $scope.notes.unshift(note);
    $scope.open(note);
  }

  $scope.open = function(note){
    $scope.selectedNote = note;
    $scope.justOpened = true;
  }    

  $scope.open($scope.notes[0]);
});

更新

问题是该指令是在两个创建新范围的ngIf下应用的......

Answer 1

尝试在函数

之外移动selectedNote和justOpened声明

 $scope.open = function(note){
    $scope.selectedNote = note;
    $scope.justOpened = true;
  }

Answer 2

之所以发生这种情况，是因为该指令属于两个ngIf指令，它们创建了新的范围。

解决：

<input type="text" ng-model="selectedNote.title" writing-focus="$parent.$parent.justOpened">

和

writing.directive('writingFocus', function($timeout, $parse){
  return {
    restrict: 'AC',
    scope: false,
    link: function(scope, element, attrs){
      var model = $parse(attrs.writingFocus);
      scope.$watch(model, function(value){
        if(value === true){
          $timeout(function(){
            element[0].focus();
            model.assign(scope, false);
          });
        }
      });
    }
  }
});

AngularJS从指令更新控制器的范围

更新

2 个答案: