iphone - How to stop UITextView from scrolling up when entering it

Question

I have a UITextView included in a UITableViewCell. The layout is correct when the views are initially displayed, but once I click in the UITextView it automatically scrolls up a bit and the top half of the characters on the first line becomes invisible.

This image is when the UITextView is not active:
UITextView not active http://gerodt.homeip.net/uitextview-notactive.png

And this one is when I clicked in the UITextView to make it active:
UITextView active http://gerodt.homeip.net/uitextview-active.png

I do not the UITextView to scroll up at all, it should simple stay fixed. How can I achieve this? I already tried several settings in Interface Builder, but no luck so far.

Any suggestions are appreciated.

Gero

Answer 1

UITextView is a subclass of UIScrollView, so it has a configurable contentInset property. Unfortunately, if you try to change contentInset on a UITextView instance, the bottom edge inset always gets reset to 32. I've run into this before with short UITextView frames and found this to be an issue. I suspect this is what is causing your problem, but you should check the contentInset of your textview in the debugger to be sure.

The workaround/solution is simple: subclass UITextView and override the contentInset method so that it always returns UIEdgeInsetZero. Try this:

//
// BCTextView
//
// UITextView seems to automatically be resetting the contentInset
// bottom margin to 32.0f, causing strange scroll behavior in our small
// textView.  Maybe there is a setting for this, but it seems like odd behavior.
// override contentInset to always be zero.
//
@interface BCZeroEdgeTextView : UITextView
@end

@implementation BCZeroEdgeTextView

- (UIEdgeInsets) contentInset { return UIEdgeInsetsZero; }

@end