The use of selector in Android---primarily to change the default background of the ListView and button controls

Selector Property Description:

Android:state_selected selected

Android:state_focused Get Focus

android:state_pressed Click

Android:state_enabled setting whether to respond to an event, refers to all events

Use case Description:

1. Create a listview_selector.xml style file

First create a new drawable folder in the Res directory, and then in new drawable folder listview_selector.xml file , whose directory structure is: Res/drawable/< Span style= "padding:0px; margin:0px ">listview_selector.xml

2. Style edit

<?xml version= "1.0" encoding= "Utf-8"?> <selector   xmlns:android= "http://schemas.android.com/apk/res/ Android > <!--background picture by default-    -<item android:drawable= "@drawable/pic1"/>    < background picture when!--no focus-- >    <item android:state_window_focused= "false"           android:drawable= "@drawable/pic1"/>   <!-- When you get the focus in non-touch mode and click the background picture--    <item android:state_focused= "true" android:state_pressed= "true"   Android: drawable= "@drawable/pic2"/> <!--touch mode when clicked background picture--  <item android:state_focused= "false" Android: State_pressed= "true"   android:drawable= "@drawable/pic3"/>  <!--When selected picture background--    <item Android:state_selected= "true"   android:drawable= "@drawable/pic4"/>   <!--get focus when the picture background    -- <item android:state_focused= "true"   android:drawable= "@drawable/pic5"/>   </selector>

3. Refer to listview_selector . xml file

There are three ways to refer to the file you just created:

(1) Add the following property code in the ListView

Android:listselector= "@drawable/listview_selector

(2) inAdd the following property code in the ListView item interface

android:background= "@drawable/listview_selector

(3) write directly with Java code

drawable drawable = Getresources (). getdrawable (R.drawable.listview_selector); Listview.setselector (drawable);

Attention:

If the ListView has a background picture or background color, the listview background will darken when you slide the listview. You can fix this problem by setting the following properties for the ListView

Android:cachecolorhint= "@android: Color/transparent"

When you click on a ListView item, you'll notice that the background color of the item turns orange. You can fix this problem by setting the following properties for the ListView

Android:listselector= "@android: Color/transparent"

All two of the above properties are set to the background color transparent, that is, #00000000 (transparent color)

The use of selector in Android---primarily to change the default background of the ListView and button controls