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iosuislidercgaffinetransformscale

Scale UIView using UISlider

I'm trying to scale an UIView using a UISlider but the result is not good with this approach:

- (void)setScale:(float)scale {
   CGAffineTransform transform = CGAffineTransformScale(myView.transform, scale, scale);
            myView.transform = transform;

}

thanks

Solution

  • You want to change the scale based on the identity transform (which represents the object without any changes). This code works:

    - (void)sliderDidChangeValue:(id)sender
{
    // the slider
    UISlider *slider = sender;

    // get your view or use the ivar if you have it in one
    UIView *view = [self.view viewWithTag:12];

    CGAffineTransform transform = CGAffineTransformScale(CGAffineTransformIdentity, slider.value, slider.value);
    view.transform = transform;
}

    When you create the slider you may want to start the value at 1 if your view is starting at full size.