why does my cursor return null?

Question

I have below a listener to detect incoming calls
I make a query to the CallLog content provider every after an incoming call
My cursor always return null even if there was already a call logged just seconds ago
btw, I cleared my call log before running the project in eclipse
I want to be able to point my Cursor at the first row every after an incoming call but it just doesn't work

// Listener to detect incoming calls.

private class CallStateListener extends PhoneStateListener {

    @Override
    public void onCallStateChanged(int state, String incomingNumber) {

        if (previousState == TelephonyManager.CALL_STATE_RINGING
                && state == TelephonyManager.CALL_STATE_IDLE) {

            cursor = context.getContentResolver().query(
                    CallLog.Calls.CONTENT_URI, projection, null, null,
                    Calls.DEFAULT_SORT_ORDER);

            Log.i("SIZE OF CURSOR", String.valueOf(cursor.getCount()));

            if (cursor.moveToFirst()) {

            }// end if
        }// end if

        Log.i("onCallStateChanged",
                String.format("State changed to %d", state));

        previousState = state;

    }// end onCallStateChanged()
}// end CallStateListener class

Cursor cursor;
private String[] projection = new String[] { Calls.TYPE, Calls.NUMBER };

Answer 1

I similarly read calls from the log post-call and experienced some issues but have a working solution. There are two things to consider:

1) I had trouble on some devices when using the constant

CallLog.Calls.CONTENT_URI

Try using the URI string directly instead:

Uri.parse("content://call_log/calls")

2) You are reading the call log too fast after the end of a call, sleep your Listener for 1000ms to let the call log update before querying it.

Answer 2

try use local Cursor variable, ~.~ then be sure query not return null~.~