Javascript 等待angular在套接字连接后渲染元素

当有一个成功的套接字

connect

并且

angular

渲染元素时，我想触发一个函数

Ex. <canvas id="{{currentUserId}}"></canvas>

Ex。

我希望在代码中包含以下内容：

socket.on('connect',function(){
  until(<above canvas is present>)
    callMe();
});

socket.on（'connect'，function（））{
直至()
callMe（）；
});

找到了使用库的解决方案：

socket.on('connect',function(){
    async.until(
      function(){
        return $('#canvasId').length > 0;
      },
      async.ensureAsync(
        function(retry){
        console.log('trying');
        retry(null,null);
        }
      ),
      function(err,result){
        console.log('rendered');
        callMe();
      }
    );
  });

解释如下:

async.until(test,async.ensureAsync(fn),callback){}

test : return true/false, if returns false fn will be called and this will repeat until true is returned and on that final callback is called

fn: do some action, for my case I just wanted to wait, so I am not performing any action

async.ensureAsync(fn) : ensures that one fn is called in one tick and prevents stack overflow if there are too many attempts

callback: is called when test returns true

---

能否将

回调

添加到调用

套接字

的函数中？socket.on（'connect'，…）是一个事件，因此某些函数不会调用它。