ContentProvider内容提供者

ContentProvider内容提供者

ContentProvider内容提供者（四大组件之一）主要用于在不同的应用程序之间实现数据共享的功能

	有内容提供方和内容索要方
	  索要方是contentResolver
	  如果访问系统的自带数据需要加权限
	  url 是统一资源标识符

还有内容提供方 contentProvider
需要继承 ContentProlider
重写六个方法 进行创建数据库 增删改查操作

内容提供者代码

 @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        // Implement this to handle requests to delete one or more rows.
        throw new UnsupportedOperationException("Not yet implemented");
    }

    @Override
    public String getType(Uri uri) {
        // TODO: Implement this to handle requests for the MIME type of the data
        // at the given URI.
        throw new UnsupportedOperationException("Not yet implemented");
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        // TODO: Implement this to handle requests to insert a new row.
        throw new UnsupportedOperationException("Not yet implemented");
    }

    @Override
    public boolean onCreate() {
        // TODO: Implement this to initialize your content provider on startup.
        return false;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
                        String[] selectionArgs, String sortOrder) {
        // TODO: Implement this to handle query requests from clients.
        throw new UnsupportedOperationException("Not yet implemented");
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
                      String[] selectionArgs) {
        // TODO: Implement this to handle requests to update one or more rows.
        throw new UnsupportedOperationException("Not yet implemented");
    }

内容索要方代码

	 ContentResolver resolver = getContentResolver();
        Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
        String[] s = new String[]{ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER};
        Cursor cursor = resolver.query(uri, s, null, null, null);

        while (cursor.moveToNext()) {
            User user = new User();
            user.name = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
//            user.phone = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

            Log.e("user####", user.toString());
        }

  ContentResolver resolver = getContentResolver();
        Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        String[] strings = new String[]{MediaStore.Images.Media.TITLE, MediaStore.Images.Media.SIZE, MediaStore.Images.Media.DATA};
        Cursor cursor = resolver.query(uri, strings, null, null, null);

        while (cursor.moveToNext()) {
            User user = new User();
            user.name = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.TITLE));
//            user.phone=cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.SIZE));
//            user.date=cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));

            Log.e("pic####", user.toString());
        }