ANDROID content provide 使用实例

Content Provider提供了一种多应用间数据共享的方式，比如：联系人信息可以被多个应用程序访问。Content Provider是个实现了一组用于提供其他应用程序存取数据的标准方法的类。

下面来看一个简单的实例: MainActivity.java

package com.app.contentprovidetest;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle; 
import android.provider.Contacts.People;
import android.provider.Contacts;
import android.provider.ContactsContract;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.util.Log;
import android.view.Menu;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;


public class MainActivity extends Activity {
	//声明ContentResolver对象
	private ContentResolver mContentResolver= null;  
	Cursor cursor ;
	//声明联系人 Uri位置
	private Uri uri; 
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//获得ContentResolver对象	 
		mContentResolver=getContentResolver();		
		uri =ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
		//cursor取数据
		//(uri地址,显示字段，查询条件，条件参数，排序)
		cursor = mContentResolver.query(uri, null, null, null, null);
		List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
		if(cursor.getCount()>0){
			while(cursor.moveToNext()){//游标下标移动
				String  name =cursor.getString(cursor.getColumnIndex(Phone.DISPLAY_NAME));
				String phone =cursor.getString(cursor.getColumnIndex(Phone.DATA));
				Log.i("xxxxxx", "name:"+name+","+"phone"+phone);				
				HashMap<String, String> map = new HashMap<String, String>();
				map.put("name", name);
				map.put("phone", phone);
				list.add(map); 
			}
			ListView listView1 =(ListView) findViewById(R.id.listView1);
			SimpleAdapter adapter = new SimpleAdapter(MainActivity.this, list,  R.layout.listview_item,
					new String[]{"name","phone"}, new int[]{R.id.textView1,R.id.textView2}); 
			listView1.setAdapter(adapter);
		}  
		insert();//添加系统ContentProvider 内容
	}
	private  void insert() {
			//获得ContentResolver对象实例
	   ContentResolver  cr=getContentResolver();
		//将添加的信息封装到ContentValues对象
		 ContentValues  values = new ContentValues();
		 //定义Uri 
		 Uri uri = Contacts.People.CONTENT_URI;
		 //添加姓名
		 values.put(People.NAME, "Android"); 
		 //添加电话号
		 values.put(People.NUMBER, "12345");
		 //执行添加操作
		 cr.insert(uri, values); 
		 Toast.makeText(getApplicationContext(), "添加成功" , Toast.LENGTH_SHORT).show();
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);  
		return true;
	}
 
}

R.Layout.XML文件 listview_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

    </LinearLayout>

</LinearLayout>

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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=".MainActivity" >
 
    <ListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/textView1"
        android:layout_below="@+id/textView1" >
    </ListView>

</RelativeLayout>