如何在某个功能完成后才能执行某个功能？

Question

Event.observe(document, 'dom:loaded', function() { 

    new Ajax.Request('/HumblFin/Serv', { 
     method:'get', 
     onSuccess: function(transport){ 
      var data = transport.responseText.evalJSON(); 
      drawChart(data); 
     }, 
     onFailure: function(){ alert('Something went wrong...') } 
    }); 


function drawChart(data) 
{ 

    for (var i = 0; i < data.jobs.length; i++) { 
     priceData.push([i, data.jobs[i].INCPU]); 
     dateData.push(data.jobs[i].Dater); 

     } 
} 

此后完成drawchart(data)方法我只想执行下面的代码 ，但不幸的是，函数HumbleFinance.init正在用空数据调用。

请告诉我如何解决这个问题。 我不能把下面的代码放在drawChart（数据）函数中

HumbleFinance.init('finance', priceData , dateData); 
Event.observe(HumbleFinance.containers.summary, 'flotr:select', function (e) { 

    var area = e.memo[0]; 
    xmin = Math.floor(area.x1); 
    xmax = Math.ceil(area.x2); 

    var date1 = dateData[xmin]; 
    var date2 = dateData[xmax]; 

    $('dateRange').update(dateData[xmin] + ' - ' + dateData[xmax]); 

}); 
}); 

Answer 1

你得到你的Ajax响应并处理数据结果之前，您对HumbleFinance.init()呼叫正在发生的事情里面。在您致电init之前，您需要确保处理您的ajax响应。为此，只需将init呼叫移动到onSuccess回调内，然后调用drawChart方法。

<script> 
Event.observe(document, 'dom:loaded', function() { 

    new Ajax.Request('/HumblFin/Serv', { 
     method:'get', 
     onSuccess: function(transport){ 
      var data = transport.responseText.evalJSON(); 
      drawChart(data); 

      //Put your HumbleFinance.init call here, 
      //after the priceData and dateData has been generated. 
      HumbleFinance.init('finance', priceData , dateData); 
     }, 
     onFailure: function(){ alert('Something went wrong...') } 
    }); 

    Event.observe(HumbleFinance.containers.summary, 'flotr:select', function (e) { 

     var area = e.memo[0]; 
     xmin = Math.floor(area.x1); 
     xmax = Math.ceil(area.x2); 

     var date1 = dateData[xmin]; 
     var date2 = dateData[xmax]; 

     $('dateRange').update(dateData[xmin] + ' - ' + dateData[xmax]); 

    }); 
});