contentprovider中UriMatcher matcher用法

1. 首先还是定义一个类继承contentprovider

package com.bwf.provider_01;

import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.net.Uri;
import android.util.Log;

public class DataProvider extends ContentProvider{
    public static final Uri uri = Uri.parse("content://com.fanhy.provider/");
    static UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
    final static int DATAS = 0;
    final static int DATA = 1;
    
    DataHelper helper;
    SQLiteDatabase db;
    
    // 注册Uri
    static{
        matcher.addURI("com.fanhy.provider", "per", DATAS);
        matcher.addURI("com.fanhy.provider", "per/#", DATA);
    }
    @Override
    public boolean onCreate() {
        myLog("onCreate");
        helper = new DataHelper(getContext(), "Person.db", null, 1);
        db = helper.getReadableDatabase();
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
            String[] selectionArgs, String sortOrder) {
        myLog("query");
        switch (matcher.match(uri)) {
        case DATAS:
            return db.query("per", null, null, null, null, null, null);
        case DATA:
            return db.query("per", null, selection, selectionArgs, null, null, null);
        default:
            throw new IllegalArgumentException("未知的uri:"+uri);
        }
    }

    @Override
    public String getType(Uri uri) {
        myLog("getType");
        switch (matcher.match(uri)) {
        case DATAS:
            return "vnd.android.cursor.dir/com.fanhy.provider";
        case DATA:
            return "vnd.android.cursor.item/com.fanhy.provider";
        default:
            throw new IllegalArgumentException("未知的uri:"+uri);
        }
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        myLog("insert");
        switch (matcher.match(uri)) {
        case DATAS:
            long rowId = db.insert("per", null, values);
            if(rowId > 0){
                // 插入成功则返回新的把id添加进去形成新的uri
                Uri newUri = ContentUris.withAppendedId(uri, rowId);
                // 通知数据已更新
                getContext().getContentResolver().notifyChange(newUri, null);
                return newUri;
            }
            return null;
        default:
            throw new IllegalArgumentException("未知的uri:"+uri);
        }
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        myLog("delete");
        switch (matcher.match(uri)) {
        case DATAS:
            return db.delete("per", null, null);
        case DATA:
            return db.delete("per", selection, selectionArgs);
        default:
            throw new IllegalArgumentException("未知的uri:"+uri);
        }
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
            String[] selectionArgs) {
        myLog("update");
        switch (matcher.match(uri)) {
        case DATAS:
            return db.update("per", values, null, null);
        case DATA:
            return db.update("per", values, selection, selectionArgs);

        default:
            throw new IllegalArgumentException("未知的uri:"+uri);
        }
    }

    void myLog(String s){
        Log.d("fanhy", s);
    }
}

2. 创建一个类继承SQLiteOpenHealper

 1 package com.bwf.provider_01;
 2 
 3 import android.content.Context;
 4 import android.database.sqlite.SQLiteDatabase;
 5 import android.database.sqlite.SQLiteDatabase.CursorFactory;
 6 import android.database.sqlite.SQLiteOpenHelper;
 7 import android.util.Log;
 8 
 9 public class DataHelper extends SQLiteOpenHelper{
10 
11     public DataHelper(Context context, String name, CursorFactory factory,
12             int version) {
13         super(context, name, factory, version);
14     }
15 
16     @Override
17     public void onCreate(SQLiteDatabase db) {
18         String sql = "create table per(" +
19                 "_id integer primary key autoincrement," +
20                 "name varchar(8))";
21         db.execSQL(sql);
22         Log.d("fanhy", "建立表格per");
23     }
24 
25     @Override
26     public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
27         
28     }
29 
30 }

3.contentprovider的使用

package com.bwf.provider_01;

import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.database.Cursor;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
/**
 * 创建ContentProvider基本流程
 *         1.定义一个类DataProvider继承自ContentProvider
 *         2.实现其onCreate、getType、insert、delete、update、query方法
 *         3.在清单文件中注册ContentProvider
 *         4.将访问途径Uri提供出去
 * 
 *  使用ContentProvider基本流程
 *      1.通过getContentResolver获取ContentResolver对象resolver
 *      2.通过Uri对ContentProvider中的数据进行增删改查操作
 * */
public class MainActivity extends Activity {
    ContentResolver resolver;
    
    Uri uri = Uri.parse("content://com.fanhy.provider/per");
     
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        resolver = getContentResolver();
    }

    @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;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case R.id.action_add:
            ContentValues values = new ContentValues();
            values.put("name", "张三");
            resolver.insert(uri, values);
            values.put("name", "李思");
            resolver.insert(uri, values);
            values.put("name", "张五");
            resolver.insert(uri, values);
            break;
        case R.id.action_del:
            resolver.delete(uri, null, null);
            break;
        case R.id.action_update:
            ContentValues values1 = new ContentValues();
            values1.put("name", "李四儿");
            // 插入成功则返回新的把id添加进去形成新的uri
            Uri newUri = Uri.parse("content://com.fanhy.provider/per");
            resolver.update(newUri, values1, "name = '李思'", null);
            break;
        case R.id.action_search:
            Cursor c = resolver.query(uri, null, null, null, null);
            while(c.moveToNext()){
                String name = c.getString(c.getColumnIndex("name"));
                Log.d("fanhy", name);
            }
            break;

        default:
            break;
        }
        return super.onOptionsItemSelected(item);
    }
}

4.当然还是的注册provider

posted on 2015-10-14 22:18 敬的男人阅读(386) 评论(0) 收藏举报