// 点击按钮触发的保存方法，该方法把数据存储在xml文件中
public void save(View v) {
String name = nameText.getText().toString();
String age = ageText.getText().toString();
// 把一个String的数据类型转换为一个int类型
service.save(name, Integer.valueOf(age));
Toast.makeText(getApplicationContext(), "保存成功", 1).show();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
nameText = (EditText) findViewById(R.id.edt_name);
ageText = (EditText) findViewById(R.id.edt_age);
service = new PreferencesService(this);
Map<String, String> params = service.getPreferences();
nameText.setText(params.get("name"));
ageText.setText(params.get("age"));
}