Android SharedPreferences

Android SharedPreferences

Develop > API Guides >数据存储
https://developer.android.com/guide/topics/data/data-storage.html#pref
https://www.youtube.com/watch?v=HWKcVeNcs20&index=11&list=PLHOqLxXumAI-ASmOAbuV9oD-gxHvjsjUU

文件的写入位置
System.out: /data/data/com.example.e560.m1110a/shared_prefs/xml.xml

<?xml version='1.0' encoding='utf-8' standalone='yes' ?>
<map>
    <boolean name="chk" value="true" />
    <string name="key">new value</string>
    <set name="StringSet">
        <string>String1</string>
        <string>String2</string>
    </set>
    <int name="int" value="123" />
</map>

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setinfo();
        addinfo();
        getinfo();
        File f = new File("/data/data/com.example.e560.m1110a/shared_prefs");
        System.out.println("----------");
        File[] fs = f.listFiles();
        System.out.println(fs.length);
        for (int i = 0; i < fs.length; i++) {
            File temp = fs[i];
            System.out.println(temp.getPath());
        }
    }

    protected void getinfo() {
        SharedPreferences sp = this.getSharedPreferences("xml", MODE_PRIVATE);
        LinearLayout lv = new LinearLayout(this);
        EditText et = new EditText(this);
        et.setText(sp.getAll().toString());
        lv.addView(et);
        setContentView(lv);
    }

    protected void setinfo() {
        SharedPreferences sp = this.getSharedPreferences("xml", MODE_PRIVATE);
        SharedPreferences.Editor edit = sp.edit();
        edit.putString("key", "value");
        edit.putInt("int", 123);
        edit.putBoolean("chk", true);
        edit.commit();
    }

    protected void addinfo() {
        SharedPreferences sp = this.getSharedPreferences("xml", MODE_PRIVATE);
        SharedPreferences.Editor edit = sp.edit();
        edit.putString("key", "new value");
        Set<String> list = new HashSet<String>();
        list.add("String1");
        list.add("String2");
        edit.putStringSet("StringSet", list);
        edit.commit();
    }
}