android - 联系人存在于联系人中

Question

我有电话号码。有什么方法可以检查电话号码是否存在于设备的联系人数据库中？取决于我需要在我的应用程序中进一步移动。请提出建议，或者如果有人可以提供示例代码 fragment ，请提供。

下面是我写的代码:

public boolean contactExists(Activity _activity, String number) {
    String[] mPhoneNumberProjection = { PhoneLookup._ID, PhoneLookup.NUMBER, PhoneLookup.DISPLAY_NAME };
    Cursor cur = _activity.getContentResolver().query(number, mPhoneNumberProjection, null, null, null);
    try {
        if (cur.moveToFirst()) {
            return true;
        }
    } finally {
        if (cur != null)
            cur.close();
    }
    return false;
}// contactExists

提前致谢...

Answer 1

public boolean contactExists(Activity _activity, String number) {
    if (number != null) {
        Uri lookupUri = Uri.withAppendedPath(PhoneLookup.CONTENT_FILTER_URI, Uri.encode(number));
        String[] mPhoneNumberProjection = { PhoneLookup._ID, PhoneLookup.NUMBER, PhoneLookup.DISPLAY_NAME };
        Cursor cur = _activity.getContentResolver().query(lookupUri, mPhoneNumberProjection, null, null, null);
        try {
            if (cur.moveToFirst()) {
                return true;
            }
        } finally {
            if (cur != null)
                cur.close();
        }
        return false;
    } else {
        return false;
    }
}// contactExists

处理空指针异常。