这是我的代码
home.xml
<item android:id="@+id/action_shopping_cart" android:actionLayout="@layout/action_bar_cart_button" android:showAsAction="ifRoom" android:title="Shopping Cart" /> <item android:id="@+id/action_notifications" android:actionLayout="@layout/action_bar_notifications_button" android:showAsAction="ifRoom" android:title="Notifications" /> <item android:id="@+id/menu_overflow" android:orderInCategory="100" android:icon="@drawable/ic_action_overflow" android:showAsAction="always" android:title="OverFlow"> <menu> <item android:id="@+id/action_my_account" android:orderInCategory="100" android:showAsAction="never" android:title="My Account" /> <item android:id="@+id/action_current_orders" android:orderInCategory="100" android:showAsAction="never" android:title="My Orders" /> <item android:id="@+id/action_wish_list" android:orderInCategory="100" android:showAsAction="never" android:title="My Wishlist" /> <item android:id="@+id/action_contact_us" android:orderInCategory="100" android:showAsAction="never" android:title="Contact Us" /> <item android:id="@+id/action_logout" android:orderInCategory="100" android:showAsAction="never" android:title="logout" /> </menu> </item>
我想要View“menu_overflow”我怎么能得到它?
我试过以下方式:
Activity.java代码
public boolean onCreateOptionsMenu(Menu menu){
final MenuItem item = menu.findItem(R.id.menu_overflow); View view = (View) findViewById(R.id.menu_overflow); new MaterialShowcaseView.Builder(this) .setTarget(mOverFlowIcon) .setRadius(10) .setMaskColour(Color.argb(150,0)) .setContentText("Find Your Wishlist Here") // optional but starting animations immediately in onCreate can make them choppy .setDismissOnTouch(true) .show(); return super.onCreateOptionsMenu(menu); }
但是返回视图是null.
请帮忙… thanx
解决方法
你在onCreateOptionsMenu中夸大菜单吗?看来,当执行onCreateOptionsMenu时,xml通胀会被添加到事件队列中,而不是立即膨胀.这是执行findViewById()时导致空指针的原因.尝试将视图查找放在Handler中.处理程序中的代码将添加到消息队列中,因此将在菜单膨胀后执行.这将解决您的空指针.它看起来像这样:
@Override 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); new Handler().post(new Runnable() { @Override public void run() { View view = (View) findViewById(R.id.menu_overflow); new MaterialShowcaseView.Builder(this) .setTarget(view) .setRadius(10) .setMaskColour(Color.argb(150,0)) .setContentText("Find Your Wishlist Here") // optional but starting animations immediately in onCreate can make them choppy .setDismissOnTouch(true) .show(); } }); return true; }