One of Android three pop-up boxes Poprpwindow

Poprpwindow

In the Android pop-up box I currently learned that there are three kinds: alertdialog,poprpwindow,activity pseudo-bullet box,

　　Alertdialog is so familiar, it's not introduced here.

Let's see Poprpwindow.

The explanations given by the API are:

　　

It means a pop-up form showing the view that will float on top of the current activity,

The difference between it and alertdialog is that there are two ways to pop up a box in Android: Alertdialog and Popupwindow, which are different:
1, the position of Alertdialog fixed, and the position of Popupwindow can be arbitrary;
2. Alertdialog is non-blocking thread, while Popupwindow is blocking thread

　　Here's an example to illustrate the use of Popupwindow:

Activity.class:

1  Public classMainactivityextendsActivity {2 3     PrivateButton btn;4 5 @Override6     protected voidonCreate (Bundle savedinstancestate) {7         Super. OnCreate (savedinstancestate);8 Setcontentview (r.layout.activity_main);9BTN =(Button) Findviewbyid (r.id.show);TenBtn.setonclicklistener (NewButton.onclicklistener () { One              A @Override -              Public voidOnClick (View v) { -Popupwindow Popupwindow =NewPopupwindow (mainactivity. This); the                 //here is a ListView displayed in Popupwindow, you can also load a xx.xml file (Layoutfalter.from (). Inflate ()) -ListView ListView =NewListView (mainactivity. This);  -arrayadapter<string> adapter =NewArrayadapter<string> (mainactivity. ThisAndroid. R.layout.simple_dropdown_item_1line,Newstring[]{"First", "second"}); - Listview.setadapter (adapter); +Popupwindow.setcontentview (ListView);//the view to be displayed in the Popupwindow -Popupwindow.setheight (500); +Popupwindow.setwidth (180); APopupwindow.setoutsidetouchable (true);//false By default outside of the Popupwindow range atPopupwindow.setbackgrounddrawable (NewColordrawable (Color.argb (50, 52, 53, 55))); -                 /** - * Popupwindow.showasdropdown (anchor, Xoff, Yoff) is used to mark where the Popupwindow is to be displayed - * Anchor: To the view as the standard location - * Xoff: The x offset at the base position of the anchor - * Yoff: The y offset at the base position of the anchor in                  */ -Popupwindow.showasdropdown (btn, 0, 0); to                  +             } -         }); the          *     } $ Panax Notoginseng @Override -      Public BooleanOncreateoptionsmenu (Menu menu) { the getmenuinflater (). Inflate (R.menu.main, menu); +         return true; A     } the  +}

The corresponding XML file contains a button that is not posted.

Source code Download: Source code