我想在操作欄內放置一個通知計數器,它給了我這個錯誤該onCreateOptionsMenu
方法中:NullPointerException:試圖調用空虛對象引用虛擬方法'android.view.View android.widget.RelativeLayout.findViewById(int)'
java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.widget.RelativeLayout.findViewById(int)' on a null object reference
at ro.oce.store.MainActivity.onCreateOptionsMenu(MainActivity.java:112)
at android.app.Activity.onCreatePanelMenu(Activity.java:2823)
at android.support.v4.app.FragmentActivity.onCreatePanelMenu(FragmentActivity.java:262)
at android.support.v7.internal.view.WindowCallbackWrapper.onCreatePanelMenu(WindowCallbackWrapper.java:85)
at android.support.v7.app.AppCompatDelegateImplBase$AppCompatWindowCallbackBase.onCreatePanelMenu(AppCompatDelegateImplBase.java:241)
at android.support.v7.internal.view.WindowCallbackWrapper.onCreatePanelMenu(WindowCallbackWrapper.java:85)
at android.support.v7.internal.app.ToolbarActionBar.populateOptionsMenu(ToolbarActionBar.java:448)
at android.support.v7.internal.app.ToolbarActionBar$1.run(ToolbarActionBar.java:65)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
下面是代碼:
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
RelativeLayout badgeLayout = (RelativeLayout) menu.findItem(R.id.shopping_cart).getActionView();
TextView tv = (TextView) badgeLayout.findViewById(R.id.actionbar_notifcation_textview);
tv.setText("12");
return true;
}
之前,我添加了最後3行代碼,我的應用程序沒有產生任何錯誤。有人能幫幫我嗎?
有一件事你如何在menu.xml中使用'RelativeLayout' –
這種方式將不會工作 – Gattsu
@sourabhbans這是行不通的。它說不兼容的類型'必需:android.view.View''發現:無效' – Pikachuu