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UIScrollView does not respect minimumZoomScale after changing view

I am facing the problem of getting the correct UIScrollView update in response to changing the minimum zoom scale.

The scrollview has a UIImageView as a preview, and the UIImageView image property is set in response to the didFinishPickingMediaWithInfo UIPickerView method:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    UIImage *takenImage = [info objectForKey:UIImagePickerControllerOriginalImage];

    [self.imageView setImage:takenImage];
    [self.imageView setFrame:CGRectMake(self.imageView.frame.origin.x, self.imageView.frame.origin.y, takenImage.size.width, takenImage.size.height)];

    [self.scrollView setContentSize:CGSizeMake(takenImage.size.width, takenImage.size.height)];

    [self.scrollView setMinimumZoomScale:[self.scrollView frame].size.width / takenImage.size.width];
    [self.scrollView setMaximumZoomScale:2.0];
    [self.scrollView setZoomScale:[self.scrollView minimumZoomScale] animated:YES];

    [self dismissModalViewControllerAnimated:YES];        

}

This works correctly when you first add an image using this method. However, if this method starts again - even to add the same image as for the first time - the subsequent image is displayed in full size in scrollView and cannot be reduced - only enlarged.

I dropped the contentSize, zoomScale, minimumZoomScaleand maximumZoomScalescrollView logged, and every time they are the same. minimumZoomScalecounted correctly every time.

scrollView minimumZoomScale 1.0, , . - , ?

+3
1

, - , - - , - 1.0.

: Reset zoomScale 1.0 :

// See http://stackoverflow.com/questions/10586577
// first reset before new content size
scroller.zoomScale = 1.0f;
// set new content size
scroller.contentSize = newImage.size;
// ... adjust minimum/maximum zoom scales if needed
+13

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