Android之Shared Preferences

懒得再翻译，这段应该很好理解，直接将Dev Guide中复制过来。

The SharedPreferences class provides a general framework that allows you to save and retrieve persistent key-value pairs of primitive data types. You can use SharedPreferences to save any primitive data: booleans, floats, ints, longs, and strings. This data will persist across user sessions (even if your application is killed).

To get a SharedPreferences object for your application, use one of two methods:

getSharedPreferences() - Use this if you need multiple preferences files identified by name, which you specify with the first parameter.
getPreferences() - Use this if you need only one preferences file for your Activity. Because this will be the only preferences file for your Activity, you don't supply a name.

To write values:

Call edit() to get a SharedPreferences.Editor.
Add values with methods such as putBoolean() and putString().
Commit the new values with commit()

To read values, use SharedPreferences methods such as getBoolean() and getString().

Here is an example that saves a preference for silent keypress mode in a calculator:

1publicclassCalcextendsActivity

{
2publicstaticfinalStringPREFS_NAME="MyPrefsFile";
3
4@Override
5protectedvoidonCreate(Bundlestate)

{
6super.onCreate(state);
7...
8
9//Restorepreferences
10SharedPreferencessettings=getSharedPreferences(PREFS_NAME,0);
11booleansilent=settings.getBoolean("silentMode",false);
12setSilent(silent);
13}
14
15@Override
16protectedvoidonStop()

{
17super.onStop();
18
19//WeneedanEditorobjecttomakepreferencechanges.
20//Allobjectsarefromandroid.context.Context
21SharedPreferencessettings=getSharedPreferences(PREFS_NAME,0);
22SharedPreferences.Editoreditor=settings.edit();
23editor.putBoolean("silentMode",mSilentMode);
24
25//Committheedits!
26editor.commit();
27}
28}

Android之Shared Preferences

Android之Shared Preferences

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