Proper way to init a UIView with .xib and backing class

I have some custom created UIViews that use .xib files for layout, and backing classes for extra setup. I create these classes using alloc/init and calling loadNibNamed in my custom init method but in doing so was causing memory leak. Someone pointed out that the alloc portion actually created a self object that was leaking so I adjusted my init method to this one:

- (id)init 
{
    [self autorelease];
    self = [[[[NSBundle mainBundle] loadNibNamed:@"AssignmentView" owner:nil options:nil] lastObject] retain];
    [self setupBranding];

    UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapDetected:)];
    [self addGestureRecognizer:tapRecognizer];
    [tapRecognizer release];

    return self;
}

However, now when I run analyze code I get this warning "Returning 'self' while it is not set to the result of '[(super or self) init...]'". So my question is what is the correct way for doing custom UIViews with a backing class?

Since it was asked I'd used this above code like this:

AssignmentView * assignmentView = [[AssignmentView alloc] init];
[self.view addSubview:assignmentView];