Facebook JavaScript SDK：在返回所有查詢後運行一些東西

Question

我想用Facebook JavaScript API來計算朋友的性別。問題是FB SDK基於異步調用，因此在所有查詢完成後，我無法觸發。

例如，下面是計算我擁有多少男性/女性朋友的代碼。但最後一行將不起作用，因爲它可以在FB.api（）仍在運行時執行。

處理這個問題的最佳方法是什麼？

FB.api('/me/friends', function(response) { 
    if(response.data) { 
     var genderCount = {}; 

     $.each(response.data, function(index, friend) { 
      FB.api('/' + friend.id, function(frienddata) { 
       if (frienddata.gender) { 
        if (genderCount[frienddata.gender]) { 
         genderCount[frienddata.gender]++; 
        } 
        else { 
         genderCount[frienddata.gender]=1; 
        } 
       } 
      }); 
     }); 
}); 

// later do something with genderCount 

alert('I have ' + genderCount['male'] + ' male friends'); // won't work 

Answer 1

首先，你可能想使用更高效的fql查詢，如

SELECT name, sex, uid 
FROM user 
WHERE uid in (
    SELECT uid2 
    FROM friend 
    WHERE uid1 = me() 
) 

只需將此傳遞到graph.facebook.com/fql?q=SELECT%20%name....

然後，移動警報插入到響應處理程序，在您完成數字的總結之後。

FB.api('/fql', 
    {q: "SELECT name, sex, uid FROM user WHERE uid in (SELECT uid2 FROM friend WHERE uid1 = me())"}, 
    function (response) { 
    if (response.data) { 
     var genderCount = { 
      male: 0, 
      female: 0, 
      unknown: 0 
     }; 
     response.data.forEach(function (row) { 
      genderCount[row.sex || 'unknown']++; 
     }); 
     alert(JSON.stringify(genderCount)); 
    } 
}); 

Answer 2

FB.api('/me/friends', function(response) 
{ 
if(response.data) 
{ 
    var genderCount = {}; 
    var i = 0; 
    function GetGender(friend_id) 
    { 
     FB.api('/' + friend_id, function(frienddata) 
     { 
      if (frienddata.gender) 
      { 
       if (genderCount[frienddata.gender]) 
       { 
        genderCount[frienddata.gender]++; 
       } 
       else 
       { 
        genderCount[frienddata.gender]=1; 
       } 
      } 

      if(i == response.data.length - 1) 
      { 
       Results(genderCount); 
      } 
      else 
      { 
       GetGender(response.data[++i].id); 
      } 
     }); 
    } 

    GetGender(response.data[i].id); 
} 
}); 


function Results(genderCount) 
{ 
// here you are after all the calls 
}