Android -- ContentProvider

之前写过一个sqlite的博客，传送门：《Android -- Android JUint 与 Sqlite》，这次写的Android四大组件之一的内容提供者，我拿ContentProvider从自己的程序里面读数据。所以需要用到以前的sqlite工程。

在sqlite工程中设置提供Content Provider                                    

新建一个类，继承于ContentProvider。

在配置文件中设置：

<provider
            android:name="com.yuyidong.sqlite.PersonDBProvider"
            android:authorities="com.yuyidong.sqlite.personprovider" >
        </provider>

public class PersonDBProvider extends ContentProvider {
    
    private static UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
    private static final int INSERT = 1;
    private static final int DELETE = 21;
    private static final int UPDATE = 3;
    private static final int QUERY = 4;
    private PersonSQLite sqlite;

    static {
        matcher.addURI("com.yuyidong.sqlite.personprovider", "insert", INSERT);
        matcher.addURI("com.yuyidong.sqlite.personprovider", "delete", DELETE);
        matcher.addURI("com.yuyidong.sqlite.personprovider", "update", UPDATE);
        matcher.addURI("com.yuyidong.sqlite.personprovider", "query", QUERY);
    }
    
    
    @Override
    public boolean onCreate() {
        sqlite = new PersonSQLite(getContext());
        return false;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
            String[] selectionArgs, String sortOrder) {
        if(matcher.match(uri) == QUERY)
        {
            SQLiteDatabase db = sqlite.getReadableDatabase();
            Cursor  cursor = db.query("person", projection, selection, selectionArgs, null, null, sortOrder);
            return cursor;
        }
        else
        {
            throw new IllegalArgumentException("路径不匹配，不能执行查询操作");
        }
        
    }

    @Override
    public String getType(Uri uri) {
        // TODO 自动生成的方法存根
        return null;
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        // TODO 自动生成的方法存根
        return null;
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        // TODO 自动生成的方法存根
        return 0;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
            String[] selectionArgs) {
        // TODO 自动生成的方法存根
        return 0;
    }

}

这里static静态块里面的意思就是这个意思：content://com.yuyidong.sqlite.personprovider/insert

这个意思。  

新建工程，用来访问sqlite中的数据库                                             

private Button btn_query;

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

        btn_query = (Button) findViewById(R.id.btn_query);
        btn_query.setOnClickListener(new buttonLisnter());
    }

    class buttonLisnter implements OnClickListener {

        @Override
        public void onClick(View v) {
            ContentResolver resolver = getContentResolver();
            Uri uri = Uri
                    .parse("content://com.yuyidong.sqlite.personprovider/query");
            Cursor cursor = resolver.query(uri, null, null, null, null);
            while (cursor.moveToNext()) {
                String name = cursor.getString(cursor.getColumnIndex("name"));
                String id = cursor.getString(cursor.getColumnIndex("id"));
                System.out.println("name=" + name + "-----id=" + id);
            }

        }

    }

点击button之后获取数据。

我是天王盖地虎的分割线                                                                

源代码：http://pan.baidu.com/s/1dD1Qx01

ContentProvider4Sqlite1.zip

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