AngularJS如何编译和呈现页面

var app = angular.module(‘myApp‘,[]);

app.directive(‘contentItem‘, function($compile){
    var imageTemplate = ‘...href="{{rootDirectory}}{{content.data}}"...‘;
    var videoTemplate = ‘..ng-src="{{content.data}}"...‘;
    var noteTemplate = ‘...{{content.title}}...‘;
    
    var getTemplate = function(contentType){
        var template = ‘‘;
        
        switch(contentType){
            case ‘image‘:
                template = imageTemplate;
                break;
            case ‘video‘:
                template = videoTemplate;
                break;
            case ‘notes‘:
                template = noteTemplate;
                break;
        }
        
        return template;
    }
    
    
    var linker = function($scope, element, attrs){
        $scope.rootDirectory = ‘images/‘;
        element.html(getTemplate($scope.content.content_type)).show();
        $complie(element.contents())($scope);
    }
    
    return {
        restrict: "E",
        replace: true, //表示这里创建动态创建的html模板会覆盖页面中原先静态的html
        link: linker,
        scope: {
            content: ‘=‘
        }
    };
});