假设我正在使用$http将变量加载到$scope中:
- $http.get('/teachers/4').success(function(data){
- $scope.teacher = data;
- });
我的模板使用这些数据:
- Teacher: {{teacher.name}}
- <students-view students="teacher.students"></students-view>
该指令可以加载BEFORE老师完成加载,但我的指令的代码取决于正在加载的teacher.students数组:
- app.directive('studentsView',function(){
- return {
- scope: { students: '=' },controller: function($scope){
- _.each($scope.students,function(s){
- // this is not called if teacher loads after this directive
- });
- }
- };
- });
我如何得到我想要的行为?我不想停止使用$http,如果可能的话,我不想为范围分配承诺.
使用手表等待学生可用.一旦可用,您可以调用依赖它的代码,然后移除手表.如果您希望每次学生更改时执行代码,您都可以跳过删除手表.
- app.directive('studentsView',link: function($scope){
- var unwatch = $scope.$watch('students',function(newVal,oldVal){
- // or $watchCollection if students is an array
- if (newVal) {
- init();
- // remove the watcher
- unwatch();
- }
- });
- function init(){
- _.each($scope.students,function(s){
- // do stuff
- });
- }
- }
- };
- });