Zoom UILabel & Re-render font at correct size

Question

I have a multi-line UILabel that I want to enable zooming on.

I embedded it with a UIScrollView and set min zoom to .25 and max zoom to 4.

Answer 1

I tested JEzu's code in iOS 5.1 and 6 beta, it is working for a const text label, but cause other normal label require updating text content fail, i.e. the text is not changed...

I subclass the UILabel as ZoomableLabel with JEzu's answer, and apply the class as the label's custom class and it works fine.

Answer 2

I implemented Scrimmers's solution by subclassing UILabel as DetailedUILabel with overriding methods like this;

import QuartzCore

#import <QuartzCore/QuartzCore.h>

override init method, initWithFrame whichever you want.

- (id)init
{
    self = [super init];
    if (self) {
        CATiledLayer *tiledLayer = (CATiledLayer *)self.layer;
        tiledLayer.levelsOfDetailBias = 4;
        tiledLayer.levelsOfDetail = 4;
        self.opaque = YES;
    }
    return self;
}

and layerClass, class method.

+ (Class)layerClass {
    return [CATiledLayer class];
}