Objective C – Custom view and implementing init method?

The right thing to do in that case is to create another method containing the code that’s common to both -initWithFrame: and -initWithCoder:, and then call that method from both -initWithFrame: and -initWithCoder::

- (void)commonInit
{
    // do any initialization that's common to both -initWithFrame:
    // and -initWithCoder: in this method
}

- (id)initWithFrame:(CGRect)aRect
{
    if ((self = [super initWithFrame:aRect])) {
        [self commonInit];
    }
    return self;
}

- (id)initWithCoder:(NSCoder*)coder
{
    if ((self = [super initWithCoder:coder])) {
        [self commonInit];
    }
    return self;
}

Do heed the concerns outlined in Justin’s answer, particularly that any subclasses must not override -commonInit. I used that name here for its illustrative value, but you’ll probably want one that’s more closely tied to your class and less likely to be accidentally overridden. If you’re creating a purpose-built UIView subclass that’s unlikely to be subclassed itself, using a common initialization method as above is perfectly fine. If you’re writing a framework for others to use, or if you don’t understand the issue but want to do the safest possible thing, use a static function instead.

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