What is the alternative of [NSBundle mainBundle] URLForResource:withExtension: in iOS 3 SDK

I am developing an iOS app using iOS 4.2 SDK, but I want the app to run on older devices like my iPhone 2G with iOS 3.1.3. I don't know what is the alternative for this code:

NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"CoreDataApp" withExtension:@"momd"];

It crashes on my devic开发者_运维知识库e, because the URLForResource:withExtension: method is iOS 4+.

Please help. Thanks.

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You can obtain path to your resource using pathForResource:ofType: method and then convert that path to URL using for example +fileURLWithPath: method in NSURL - both apis are available starting SDK 2.0.

NSString *path = [[NSBundle mainBundle] pathForResource:@"CoreDataApp" ofType:@"momd"];
NSURL *modelURL = [NSURL fileURLWithPath:path];

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its -

NSURL *aFileURL = [NSURL fileURLWithPath: [[NSBundle mainBundle]  pathForResource:path ofType:@"aif"]];