QR code and barcode scanner for iOS7 and later
Add Privacy - Camera Usage Description to Info.plist.
##Usage
WQCodeScanner *scanner = [[WQCodeScanner alloc] init];
[self presentViewController:scanner animated:YES completion:nil];
scanner.resultBlock = ^(NSString *value) {
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:value message:@"" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
[alertView show];
};