在對話框上創建Facebook LoginButton會導致onActivityResult崩潰

Question

基本上，我想在MainActivity啟動的對話框中使用LoginButton。

編輯日志：

每次打開對話框時，應用程序崩潰並且onActivityResult拋出：

    01-22 12:20:59.775: E/AndroidRuntime(31017): FATAL EXCEPTION: main
01-22 12:20:59.775: E/AndroidRuntime(31017): Process: net.lagsoft.trivioliv2, PID: 31017
01-22 12:20:59.775: E/AndroidRuntime(31017): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=998, result=0, data=null} to activity {net.lagsoft.trivioliv2/net.lagsoft.trivioliv2.MainScreen}: java.lang.ClassCastException: android.view.ContextThemeWrapper cannot be cast to android.app.Activity
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread.deliverResults(ActivityThread.java:3365)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread.handleSendResult(ActivityThread.java:3408)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread.access$1300(ActivityThread.java:135)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1244)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.os.Handler.dispatchMessage(Handler.java:102)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.os.Looper.loop(Looper.java:136)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread.main(ActivityThread.java:5017)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at java.lang.reflect.Method.invokeNative(Native Method)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at java.lang.reflect.Method.invoke(Method.java:515)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at dalvik.system.NativeStart.main(Native Method)
01-22 12:20:59.775: E/AndroidRuntime(31017): Caused by: java.lang.ClassCastException: android.view.ContextThemeWrapper cannot be cast to android.app.Activity
01-22 12:20:59.775: E/AndroidRuntime(31017):    at com.facebook.widget.LoginButton.onActivityResult(LoginButton.java:440)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at net.lagsoft.trivioliv2.MainScreen.onActivityResult(MainScreen.java:1651)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.Activity.dispatchActivityResult(Activity.java:5423)
01-22 12:20:59.775: E/AndroidRuntime(31017):    at android.app.ActivityThread.deliverResults(ActivityThread.java:3361)
01-22 12:20:59.775: E/AndroidRuntime(31017):    ... 11 more

onActivityResult（）：

@Override
        protected void onActivityResult(int requestCode, int resultCode,Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
            Session.getActiveSession().onActivityResult(this, requestCode, resultCode, data);
        }

對話框代碼：

Dialog dialog = new Dialog(MainScreen.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);                   dialog.setContentView(R.layout.dialog_options_menu);                    dialog.setCancelable(false);
dialog.show();
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));            dialog.getWindow().setGravity(Gravity.TOP); 
LoginButton lButton =(LoginButton)dialog.findViewById(R.id.activity_login_facebook_btn_login);

好像在Facebook回調上的activityresult返回已損壞或為空，因為它位於對話框中。 （LoginButton從活動起作用）。 關於如何解決這個問題的任何想法？

Answer 1

更改onActivityResult()像這樣

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    Session.getActiveSession().onActivityResult(this, requestCode, resultCode, data);
}  

Answer 2

Session.getActiveSession()返回null這是onActivityResult() NPE的唯一方法。

問題中沒有足夠的上下文可以說明為什么它返回null 。