Angularjs ng-show 方法被调用太多次

Question

这个问题在这里已经有了答案:





Is expression inside ng-show fired after every model change in AngularJS?

(2 个回答)


8年前关闭。




我有一个循环超过 3 个事件的 ng-repeat 循环。在每个事件中，我都想检查登录用户是否是与该事件相关联的球队的球员。

问题是，我的代码进入了 is_player()每次页面加载大约 30 次。这显然会导致问题，因为它试图在不到一秒的时间内达到 30 次 GET 方法。

为什么这被调用了这么多次，我该如何解决这个问题？

<div class="list-group" ng-repeat="event in events">

     <div ng-show="is_player(event.team_id, profile.id)">
         ...
     </div>
</div>

Controller 方法

/**
     * Checks if a user is a player on the team. Need this method so that managers of a team can't rsvp if they're only a manager and not a player
     * @param team_id   - The team id of the event that we want to check if the user plays on
     * @param user_id   - The user that we want to check if they're a player of a team
     */
    $scope.is_player = function(team_id, user_id) {

        console.log('in is_player');

            $http.get(baseUrl+'v1/teams/' + team_id + '/players' + apiKey)
                .success(function(response) {

                    console.log("getting a team's players");
                    var players = response;

                    // Loop through all the players on the team
                    for(var i = 0; i < players.length; i++) {

                        //If the current player in the loop's user id matches what was passed in
                        if(players[i].user.id == user_id) {
                            return true;
                        }
                    } 

                    $scope.error = null;
                })
                .error(function(response) {
                    $scope.success = null;
                    $scope.error = 'An error occurred looking for your events. Please try again later.';
                }); 

        return false;
    }

Answer 1

ng-show由于数据绑定(bind)，每个摘要周期都在运行。当您从服务器获取“事件”的数据时，请考虑在服务器或前端对事件进行数据修剪。通常，您希望创建像 ng-show light 函数这样的函数，或者只是对应于属性上的 bool 值。