使用android中的文件描述符阅读联系人的信息

Question

我在从联系人列表中获取联系人时遇到问题。我正在使用此代码：

final Cursor Contact = cResolver.query(ContactsContract.Contacts.CONTENT_URI, null,
                ContactsContract.Contacts._ID +" = " + Contact_ID, null,null);
        Contact.moveToFirst();
        String lookupKey = Contact.getString(Contact
                .getColumnIndex(ContactsContract.Contacts.LOOKUP_KEY));

        Uri uri = Uri.withAppendedPath(
                ContactsContract.Contacts.CONTENT_VCARD_URI, lookupKey);

        AssetFileDescriptor fd = null;
        FileInputStream fis = null;

        fd = cResolver.openAssetFileDescriptor(uri, "_ID");
        fis = fd.createInputStream();
        byte[] buf = new byte[(int) fd.getDeclaredLength()];
        fis.read(buf);
        String vcardstring = new String(buf);

但我得到了Exception：

java.io.IOException: read failed: EINVAL (Invalid argument)
libcore.io.IoBridge.read(IoBridge.java:432)

任何人都能帮助我吗？

Answer 1

您可以尝试获取整行并将其保存在字符串列表中，例如：

public List<String> getAnswers(int line) {
    List<String> answerList = new ArrayList<String>();
    // Select All Query
    String selectQuery = "SELECT  * FROM " + TABLE_GERAL;

    SQLiteDatabase db = this.getWritableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);

    cursor.moveToPosition(line);

    for(int x=0; x<cursor.getColumnCount();x++){
        answerList.add(cursor.getString(x));
    }

    return answerList;
}