Android--SharedPreferences数据存储方案

package sd.he3.sharedpreferencestest;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button = findViewById(R.id.button_view);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
SharedPreferences.Editor editor = getSharedPreferences("HelloWorld",MODE_PRIVATE).edit();
editor.putString("H","HelloWorld");
editor.apply();
}
});
Button button1 = findViewById(R.id.button_2);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
SharedPreferences sharedPreferences = getSharedPreferences("HelloWorld",MODE_PRIVATE);
String H = sharedPreferences.getString("H","");
Log.d("H++++++++++>>>>>>>>>>>>", H);
}
});
}
}