Use of Android global variables

Usage scenarios:

Need to share data between multiple activity or service

1. Custom Application

 Public class extends Application {     privatenew hashmap<string, object>();                Public void put (String Key,object object) {         map.put (key, object);     }                Public Object get (String key) {         return  map.get (key);     }}

2. Modify the Androidmanifest.xml file:

<application <strong><em>android:name= "DemoApplication" </em></strong> android:icon= "@ Drawable/app "android:label=" @string/app_name ">

Note the contents of the black bold character, specifying that the program uses our own defined application.

3. Use:

Save data to a map defined in application in one of the activity

DemoApplication app = (demoapplication) getapplication () app.put ("key", "This is a test!");

Then get the data in another activity:

DemoApplication app == (String) app.get ("key"); Toast.maketext (This, value, Toast.length_long). Show ();

Note that concurrency issues are not considered here and, if needed, can be implemented by adding the associated synchronization code to the custom application.

Use of Android global variables