NSLocalizedString use issues

Typically use the following statement to the format string: NSLocalizedString (@ "IDS_READER_SETTING_SAMPLE", nil);
Would like to ask, if statement with parameters, how to express it?
If, titleStr = [NSString stringWithFormat: @ "Test% d", count];
How to Test a string proposed a similar IDS_READER_SETTING_SAMPLE string representation and stored. Strings document?

Also, if xib file has written a string by default, if not use NSLocalizedString out? How that support multiple languages?
Online experts for advice! ! !

Reply:
titleStr = [NSString stringWithFormat: NSLocalizedString (@ "Test% d", nil), count];
xib directly in the IB can be localized in
Reply:
xib can be localized directly in the IB in

Upstairs buddy, how to operate? Can you describe in detail? Thank you, ah!
Reply:
NSLocalizedString (@ "IDS_READER_SETTING_SAMPLE", nil) is an NSString, you are looking at how to use the