Android开发入门之监听ContentProvider中数据的变化

新建Aapp工程，向主页面添加一个按钮

	public void insert(View v) {
		Uri uri = Uri
				.parse("content://cn.leigo.providers.personprovider/person");
		ContentResolver resolver = this.getContentResolver();
		ContentValues values = new ContentValues();
		values.put("name", "A-App");
		values.put("phone", "18800000000");
		values.put("amount", 12000);
		resolver.insert(uri, values);
	}

该按钮向person插入一条数据

在db工程的insert方法中，

	@Override
	public Uri insert(Uri uri, ContentValues values) {
		SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
		switch (MATCHER.match(uri)) {
		case PERSONS:
			long rowid = db.insert("person", "name", values); // 主键值
			// content://cn.leigo.providers.personprovider/person/10
			// Uri insertUri =
			// Uri.parse("content://cn.leigo.providers.personprovider/person/"+
			// rowid);
			Uri insertUri = ContentUris.withAppendedId(uri, rowid);
			//发出数据变化通知
			this.getContext().getContentResolver().notifyChange(uri, null);
			return insertUri;
		default:
			throw new IllegalArgumentException("this is Unknow Uri:" + uri);
		}
	}

新建Bapp工程监听Aapp向Person表中添加数据时发生的变化

package cn.leigo.bapp;

import android.app.Activity;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;

public class MainActivity extends Activity {
	private static final String TAG = "MainActivity";

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

		Uri uri = Uri
				.parse("content://cn.leigo.providers.personprovider/person");
		this.getContentResolver().registerContentObserver(uri, true,
				new Observer(new Handler()));

	}

	private class Observer extends ContentObserver {

		public Observer(Handler handler) {
			super(handler);
		}

		@Override
		public void onChange(boolean selfChange) {
			Uri uri = Uri
					.parse("content://cn.leigo.providers.personprovider/person");
			Cursor cursor = getApplicationContext().getContentResolver().query(uri, null, null, null,
					"personid desc limit 1");
			if (cursor.moveToFirst()) {
				String name = cursor.getString(cursor.getColumnIndex("name"));
				Log.i(TAG, name);
			}
		}

	}

}