【Java转Android】28. SharedPreferences的使用

28. SharedPreferences的使用

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    Button button;
    private static final String TAG = "MainActivity";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = findViewById(R.id.btn_get);
        button.setOnClickListener(this);
        SharedPreferences preferences = getSharedPreferences("data", MODE_PRIVATE);
        if (preferences != null) {
            Log.d(TAG, "onCreate: "+preferences.getString("name",""));
            Log.d(TAG, "onCreate: "+preferences.getInt("age",0));
            Log.d(TAG, "onCreate: "+preferences.getBoolean("married",false));
        }
    }

    private void save() {
        SharedPreferences.Editor editor = getSharedPreferences("data", MODE_PRIVATE).edit();
        editor.putString("name","Tom");
        editor.putInt("age",28);
        editor.putBoolean("married",false);
        editor.apply();
    }


    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_get:
                save();
                break;
            default:
                break;
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"

android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

    <Button
        android:id="@+id/btn_get"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="保存文件"/>

</LinearLayout>