Android数据持久化：SharePreference

• SharePreference：作为Android数据持久化的一种，具有一定的便捷性，适合存储一些体积小的数据。
• 存储数据方式：键值对的方式，类似于Map；
• 利用SharePreference.Editor对象存储数据；
• 利用SharePreferences对象读取数据；
• 存储数据

SharedPreferences.Editor editor = getSharedPreferences("data",MODE_PRIVATE).edit();
                editor.putString("name","Damon");
                editor.putInt("age",28);
                editor.putBoolean("sex",false);
                editor.commit();

• 读取数据

SharedPreferences preferences = getSharedPreferences("data",MODE_PRIVATE);
                String name = preferences.getString("name",null);
                Integer age = preferences.getInt("age",18);
                Boolean sex = preferences.getBoolean("sex",false);

• 实践参考代码：

public class Main2Activity extends AppCompatActivity {

    private Button writeButton;
    private Button readButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        writeButton = (Button) findViewById(R.id.writeButton);
        readButton = (Button) findViewById(R.id.readButton);

        writeButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                SharedPreferences.Editor editor = getSharedPreferences("data",MODE_PRIVATE).edit();
                editor.putString("name","Damon");
                editor.putInt("age",28);
                editor.putBoolean("sex",false);
                editor.commit();
            }
        });

        readButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                SharedPreferences preferences = getSharedPreferences("data",MODE_PRIVATE);
                String name = preferences.getString("name",null);
                Integer age = preferences.getInt("age",18);
                Boolean sex = preferences.getBoolean("sex",false);

                Log.d("Main2Activity","------->" + name + age + sex);
            }
        });
    }
}

• 相关xml

<LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/writeButton"
            android:textAllCaps="true"
            android:text="Write"/>

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/readButton"
            android:textAllCaps="true"
            android:text="Read"/>

    </LinearLayout>

• 控制台数据输出