Basic use of sharedpreferences in Android

Sharedpreferences is the most understandable data storage technology in Android, and in fact sharedpreferences is dealing with a key-value (key-value pair) Sharedpreferences used to store some lightweight data

Instantiating a Sharedpreferences object (first step)

Sharedpreferences mysharedpreferences= getsharedpreferences ("Test",

Activity.mode_private);

Instantiating a Sharedpreferences.editor object (step Two)

Sharedpreferences.editor Editor = Mysharedpreferences.edit ();

Save the data in a putstring way

Editor.putstring ("name", "Karl");

Editor.putstring ("Habit", "sleep");

Submit Current Data

Editor.commit ();

To write data successfully using the TOAST information hint box

Toast.maketext (This, "data successfully written to sharedpreferences! " ,

Toast.length_long). Show ();

Executing the above code, Sharedpreferences will save the data in the Test.xml file, and you can export the file and view it under the Data/data of File Explorer.
So how do you read the data that has been stored? Let's see:

Similarly, an Sharedpreferences object is instantiated before reading sharedpreferences data

sharedpreferencessharedpreferences= getsharedpreferences ("Test",

Activity.mode_private);

Use the GetString method to get value, note that the 2nd parameter is the default value of value

String name =sharedpreferences.getstring ("name", "");

String habit =sharedpreferences.getstring ("Habit", "" ");

Display information using the Toast Information prompt box

Toast.maketext (This, "read the data as follows:" + "\ n" + "name:" + name + "\ n" + "habit:" + habit,

Toast.length_long). Show ();

The source code is as follows:

public class Main extends Activity

{

@Override

public void OnCreate (Bundle savedinstancestate)

{

Super.oncreate (savedinstancestate);

Setcontentview (R.layout.main);

}

public void Onclick_writedata (view view)

{

Sharedpreferences mysharedpreferences = getsharedpreferences ("Test",

Activity.mode_private);

Sharedpreferences.editor Editor = Mysharedpreferences.edit ();

Editor.putstring ("name", "Karl");

Editor.putstring ("Habit", "sleep");

Editor.commit ();

Toast.maketext (This, "data successfully written to sharedpreferences! " ,

Toast.length_long). Show ();

}

public void Onclick_readdata (view view)

{

Sharedpreferences sharedpreferences = getsharedpreferences ("Test",

Activity.mode_private);

String name = sharedpreferences.getstring ("name", "");

String habit = sharedpreferences.getstring ("Habit", "" ");

Toast.maketext (This, "read the data as follows:" + "\ n" + "name:" + name + "\ n" + "habit:" + habit,

Toast.length_long). Show ();

}

}

Basic use of sharedpreferences in Android