iphone - a question about UITextView and its size

Question

I have a UITextView that is supposed to have one line of text.

The size font is controlled by a slider. As the user controls the slider, I calculate the new UITextView size using (this is the method called by the slider as it moves).

- (void) changeFontSize:(id)sender {
    UISlider *slider = (UISlider *)sender;
    CGFloat newSize = (CGFloat)[slider value];

    myTextView.font = [UIFont boldSystemFontOfSize:newSize];
    [self adjustBoxforSize:myTextView.text];
}

- (void) adjustBoxForSize:(NSString*)myText {

    CGFloat fontSize = myTextView.font.pointSize;

    CGSize newSize = 
        [myText sizeWithFont:[UIFont boldSystemFontOfSize:fontSize]];
    newSize.width = newSize.width * 1.5; // make it 50% larger 
    newSize.height = newSize.height * 1.5; // make it 50% taller
    CGRect myFrame = CGRectMake(0.0f, 0.0f, newSize.width, newSize.height);
    myTextView.frame = myFrame;
}

If I reduce the font, this is the result

The question is: how can the text be out of the textview if I am scaling it to fit and indeed making it 50% larger??

am I missing something? It seems that sizeWithFont is not calculating the size correctly.

Thanks.

Answer 1

Maybe I'm wrong, but this:

newSize.width = fontSize.width * 1.5; // make it 50% larger 
newSize.height = fontSize.height * 1.5; // make it 50% taller

Shouldn't be like this?

newSize.width = newSize.width * 1.5; // make it 50% larger 
newSize.height = newSize.height * 1.5; // make it 50% taller

Otherwise you are using font size instead of the computed text size.

Answer 2

TextView has paddings that don't grow with the view size. Adding a fixed amount to the computed size of the text do the trick. Something like this:

newSize.width = newSize.width + 20; 

20 seems a good number for you case, but you can try tweaking it.