Java 向上按钮不起作用'；不要停止导航

当用户按下操作栏中的

向上按钮时，我试图在片段中进行非空字段检查（该字段实际上为空），但我得到了下一个错误：

03-24 10:56:57.860 23770-23770/com.crimes.george.crime E/WindowManager: android.view.WindowLeaked: Activity com.bubbles.george.mybubbletea.PagerActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b2fc7268 V.E..... R.....I. 0,0-480,204} that was originally added here

at android.view.ViewRootImpl.<init>(ViewRootImpl.java:348)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:286)
at com.bubbles.george.crimes.Fragment.onOptionsItemSelected(Fragment.java:142)
at android.support.v4.app.Fragment.performOptionsItemSelected(Fragment.java:2099)
at android.support.v4.app.FragmentManagerImpl.dispatchOptionsItemSelected(FragmentManager.java:2238)
at android.support.v4.app.FragmentController.dispatchOptionsItemSelected(FragmentController.java:329)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:410)
at android.support.v7.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:167)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:100)
at android.support.v7.widget.ToolbarWidgetWrapper$1.onClick(ToolbarWidgetWrapper.java:192)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)

我所期望的是在字段中有内容时导航到上一个活动，否则会出现一个对话框窗口并停止导航。但是，我得到的不是这个对话框，而是几微秒，然后导航继续到我当前活动的最高层

我做错了什么

提前感谢。
您是否尝试添加
返回true显示对话框后？我认为您正在陷入另一种情况或该方法的默认实现，这导致了导航。@DanailAlexiev谢谢。我很笨。我没发现我没有这个，它成功了。：）
 case android.R.id.home:
     Log.d(TAG, "up button in action bar has been pressed!");
     String titleField = mTitleField.getText().toString();
     if (TextUtils.isEmpty(titleField)) {
         AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
         builder.setMessage(R.string.empty_title_message)
                .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
         builder.create()
                .show();
    } else {
        NavUtils.navigateUpFromSameTask(getActivity());
        return true;
    }