16_采用SharedPreferences保存用户偏好设置参数

按钮事件

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="save"
        android:text="保存" />

package cn.itcast.SharedPreference;

import java.util.Map;

import cn.itcast.service.PreferenceService;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */
    private EditText nameText = null;
    private EditText ageText = null;
    PreferenceService svr = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        nameText = (EditText) this.findViewById(R.id.name);
        ageText = (EditText) this.findViewById(R.id.age);
        svr = new PreferenceService(this);
        
        Map<String, String> params = svr.getPreference();
        nameText.setText(params.get("name"));
        ageText.setText(params.get("age"));
    }
    
    public void save(View v) {
        String nameString = nameText.getText().toString();
        String ageString = ageText.getText().toString();
        //获取Preferences的第二种方法
        //this.getPreferences(MODE_PRIVATE);
        svr.save(nameString, Integer.valueOf(ageString));
        Toast.makeText(getApplicationContext(), R.string.success, Toast.LENGTH_LONG).show();
    }

}

package cn.itcast.service;

import java.util.HashMap;
import java.util.Map;

import javax.security.auth.PrivateCredentialPermission;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;

public class PreferenceService {

    private Context context;
    public PreferenceService(Context context) {
        this.context = context;
    }
    /**
     * 保存参数
     * @param name
     * @param age
     */
    public void save(String name, Integer age) {

        
        // TODO Auto-generated method stub
        SharedPreferences preferences = context.getSharedPreferences("itcast", Context.MODE_PRIVATE);
        Editor editor = preferences.edit();
        editor.putString("name", name);
        editor.putInt("age", age);
        editor.commit();
    }
    
    
    public Map<String, String> getPreference() {
        Map<String, String> params = new HashMap<String, String>();
        SharedPreferences preferences = context.getSharedPreferences("itcast", Context.MODE_PRIVATE);
        params.put("name", preferences.getString("name", ""));
        params.put("age", String.valueOf(preferences.getInt("age", 0)));
        return params;
        
    }    

}