安卓存储数据之SharedPreferences（偏好设置存储）

这只是个测试方法，用于记录项目被开启的次数

MainActivity

package com.chuanxidemo.shaoxin.demo06;

import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

public class MainActivity extends AppCompatActivity {

    //数据存储(偏好设置存储)
    private SharedPreferences sharedPreferences;//他是一个接口
    private SharedPreferences.Editor editor;
    private int nOpenNum;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //获取App打开次数
        sharedPreferences = getSharedPreferences("test.xml",MODE_APPEND);//第一个参数是存储文件，第二个是存储方式
        nOpenNum = sharedPreferences.getInt("count",0);
        Log.i("msg", "onCreate: "+nOpenNum);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        //存储App打开次数
        editor = sharedPreferences.edit();
        nOpenNum++;
        editor.putInt("count",nOpenNum);
        editor.commit();
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.chuanxidemo.shaoxin.demo06.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!" />
</RelativeLayout>