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;

    }

}