内容提供者复习——短信备份

 对于上一节的相亲神器，大家应该知道怎么用内容提供者去得到系统的数据 进行开发了。

其实对于大部分的URI 可以百度去得到，但是我建议自己倒弄出源码 自己去研究下。

短信URI   content://sms/ 

短信的数据库第一个是id ，第二个是address （地址）第三个日期 （date）第四个type（类型）第五个是body（内容）

demo的思路主要是 拿到接口以后 直接查询  然后序列化到本地 储存起来 保存在SD卡 ，记住加权限还有读取短信的权限

先看实体类吧  因为查询到结果需要储存起来

package com.example.backSms.entrys;

public class Smsinfo {
	private int id;
	private int type;
	private String address;
	private String body;
	private long date;
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public int getType() {
		return type;
	}
	public void setType(int type) {
		this.type = type;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getBody() {
		return body;
	}
	public void setBody(String body) {
		this.body = body;
	}
	public long getDate() {
		return date;
	}
	public void setDate(long date) {
		this.date = date;
	}
	public Smsinfo(int id, int type, String address, String body, long date) {
		super();
		this.id = id;
		this.type = type;
		this.address = address;
		this.body = body;
		this.date = date;
	}
	@Override
	public String toString() {
		return "Smsinfo [id=" + id + ", type=" + type + ", address=" + address
				+ ", body=" + body + ", date=" + date + "]";
	}
	public Smsinfo() {
		super();
	}
	
}

然后是主体类

<pre name="code" class="java">package com.example.backSms;

import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;

import org.xmlpull.v1.XmlSerializer;

import com.example.backSms.entrys.Smsinfo;

import android.app.Activity;
import android.content.ContentResolver;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.util.Xml;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }
     /**备份短信
     * @param view
     */
    public void btn(View view){
    	 //查处所有短信
    	Uri uri = Uri.parse("content://sms/");
    	ContentResolver resolver = getContentResolver();
    	Cursor cursor = resolver.query(uri, new String[]{"_id","address","date","type","body"}, null, null, null);
    	if (cursor!=null&&cursor.getCount()>0) {
    		Smsinfo smsinfo=null;
    		List<Smsinfo>list=new ArrayList<Smsinfo>();
    		while (cursor.moveToNext()) {
    			smsinfo=new Smsinfo();
    			smsinfo.setId(cursor.getInt(0));
    			smsinfo.setAddress(cursor.getString(1));
    			smsinfo.setDate(cursor.getLong(2));
    			smsinfo.setType(cursor.getInt(3));
    			smsinfo.setBody(cursor.getString(4));
    			list.add(smsinfo);
			}
			cursor.close();
			//2.序列化到本地
			writeTolocal(list);
		}
     }
    private void writeTolocal(List<Smsinfo>smsinfos){
    	XmlSerializer serializer=Xml.newSerializer();//得到序列化对象
    	//指定输出位置
    	try {
			FileOutputStream fos=new FileOutputStream("/mnt/sdcard/sms.xml");
			serializer.setOutput(fos,"utf-8");
			serializer.startDocument("utf-8", true);
			serializer.startTag(null, "smss");
			for (Smsinfo smsinfo : smsinfos) {
				serializer.startTag(null, "sms");
				serializer.attribute(null, "id", String.valueOf(smsinfo.getId()));
				serializer.startTag(null, "address");
				serializer.text(smsinfo.getAddress());
				serializer.endTag(null, "address");
				
				serializer.startTag(null, "date");
				serializer.text(String.valueOf(smsinfo.getDate()));
				serializer.endTag(null, "date");
				
				serializer.startTag(null, "type");
				serializer.text(String.valueOf(smsinfo.getType()));
				serializer.endTag(null, "type");
				
				serializer.startTag(null, "body");
				serializer.text(smsinfo.getBody());
				serializer.endTag(null, "body");
				
				serializer.endTag(null, "sms");
			}
			serializer.endTag(null, "smss");
			serializer.endDocument();
			Toast.makeText(this, "序列化备份成功", 3000).show();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			Toast.makeText(this, "备份失败", 3000).show();
			e.printStackTrace();
		}
    	
    }
}