Preferencemanager[android]

Sharedpreference is a lightweight data storage method provided by Android, which is mainly used to store simple configuration information, which is stored as a key-value pair, making it easy for us to read and deposit

Sharedpreference file is saved under /data/data/<package name>/shared_prefs Path

The Sharedpreferences object can be obtained by the Getsharedpreferences method of the activity itself.
Public abstract Sharedpreferences getsharedpreferences (String name, int mode);
Name: Represents the names of the XML files after saving
Mode: Represents the Operation permission pattern (private, readable, writable) of an XML document, using 0 or mode_private as the default mode of Operation permission.
1. Data read:

The key value of the corresponding key can be obtained by sharedpreferences the key of the object. There are different functions for different types of key values: Getboolean,getint,getfloat,getlong.
Public abstract string GetString (string key, String defvalue);

2. Data deposit:

The data is deposited through editor objects of the Sharedpreferences object . Use the editor function to set the key value, and then call commit () to commit the settings, write the XML file

Public Abstract Sharedpreferences.editor edit ();
Public abstract Sharedpreferences.editor putstring (string key, String value);
Public abstract Boolean commit ();

<?xml version= "1.0" encoding= "Utf-8"?> <linearlayout  xmlns:android= "http://schemas.android.com/apk/ Res/android "      android:orientation=" vertical "      android:layout_width=" fill_parent "      android:layout_ height= "Fill_parent" >            <textview            android:id= "@+id/textview" android:layout_width= "Fill_parent          "           android:layout_height=" wrap_content "           android:text=" @string/hello "/>        </LinearLayout>  

　　

Package com.android.test;  Import android.app.Activity;  Import android.content.SharedPreferences;  Import Android.os.Bundle;  Import Android.preference.PreferenceManager;  Import Android.widget.TextView; public class Testsharedpreferences extends activity {/** Called when the activity is first created. */@Overrid          e public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);                    Setcontentview (R.layout.main);  Sharedpreferences msharedpreferences = getsharedpreferences ("Testsharedpreferences", 0);                    Sharedpreferences msharedpreferences = preferencemanager.getdefaultsharedpreferences (this);                    int counter = Msharedpreferences.getint ("counter", 0);          TextView Mtextview = (TextView) Findviewbyid (R.id.textview);                    Mtextview.settext ("This app has been started" + Counter + "times.");      Sharedpreferences.editor meditor = Msharedpreferences.edit ();    Meditor.putint ("Counter", ++counter);                Meditor.commit ();   }  }

　　

The data must be deposited via the editor of the Sharedpreferences object, which is similar to writing to the database after depositing (put) commit!

Preferencemanager[android]