Objective C - Change System Font with Category - objective-c

Question

I want to change the default font for all UITextViews. It seems that the easiest way to do this is via custom category. I found this solution: Change the default systemFont used by controls and tried to implement it.
But my UITextViews are added programmatically so the awakeFromNib function is not called. I tried to move it to initWithFrame like this:
-(id)initWithFrame:(CGRect)frame
{
id result = [super initWithFrame:frame];
if (result) {
float size = [self.font pointSize];
NSString *stringfontstyle=self.font.fontName;
if([stringfontstyle rangeOfString:#"Bold"].location != NSNotFound) {
self.font = [UIFont fontWithName:#"Avenir-Black" size:size];
}
else if ([stringfontstyle rangeOfString:#"Italic"].location != NSNotFound) {
self.font = [UIFont fontWithName:#"Avenir-Oblique" size:size];
}
else if ([stringfontstyle rangeOfString:#"Medium"].location != NSNotFound) {
self.font = [UIFont fontWithName:#"Avenir-Medium" size:size];
}
else {
self.font = [UIFont fontWithName:#"Avenir-Roman" size:size];
}
}
return result;
}
Weird is that if my category contains initWithFrame function, the UITextView disappears. What is it that I'm missing?
Note: I'm using autoLayout so the initWithFrame is called with CGRectZero, but I suppose that isn't the problem.
EDIT:
The problem is that the font is null when the UITextView is initiated. So what method would be appropriate to place the code into?

Answer 1

when category contains a method, it overrides the class's method... and thats not good. subclassing would work.. method swizzling might be a way but...
why don't you just subclass UITextView - then you can keep your initWithFrame thingy or maybe override font
- (UIFont*)font {
if(!myFont) {
_myFont = xy;
}
id superFont = super.font;
if(![superFont.name isEqualTo:_myFont.name]) {
super.font = [myFont fontWithSize:superFont.pointSize];
}
return _myFont;
}
or setFont:
- (void)setFont:(UIFont*)newFont {
if(!myFont) {
_myFont = xy;
}
id thisFont = [_myFont fontWithSize:newFont.pointSize];
super.font = thisFont;