How can I send characters to cursor position of UISearchBar?

Question

I am trying to add a couple characters that are inconveniently located in the normal keyboard, and place them in a toolbar so that the user can use them just like normal keys.

Does anyone have a useable way to do this?

I found an article explaining how to do this by simulating a "Paste" operation, (remove pasteboard contents, replace with my character, paste into field, return original pasteboard contents) but my trouble is that I'm trying to do this with a UISearchBar, which seems to have no paste selector.

Update

I found a lead:

UIKIT_CLASS_AVAILABLE(2_0) @interface UISearchBar : UIView { 
  @private
    UITextField            *_searchField;

Since it is documented that there's a UITextField in a search bar, if I were to root through the searchbar's subviews and locate said text field, (assuming with 99% certainty that the text field has a delegate) would it make sense that I could "steal" the text field and make my class the delegate, then forward the messages to the original delegate once I'm done with them?

I'm not sure this is possible. A quick look at the `UISearchBar` documentation shows that it doesn't inherit from anything useful and there are no obvious ways to get at the cursor position and manipulate it. You might be able to write your own search bar that does this, using a UITextView and the paste idea you discovered. — Hyperbole, Aug 13 '11 at 02:14

score 1 · Answer 1 · answered Aug 13 '11 at 02:49

Can't you simply set the text of the UISearchBar? Of course, the tricky part is to determine the cursor position. For that, you can register a UITapGestureRecognizer on the UISearchBar, determine the tap co-ordinates & calculate the cursor position using - (CGSize)sizeWithFont:(UIFont *)font forWidth:(CGFloat)width lineBreakMode:(UILineBreakMode)lineBreakMode or its variants.

You may also have to register a UIPanGestureRecognizer, as the user can change the cursor position by tapping, dragging & then releasing the finger.

HTH,

Akshay

While this seems like an absolute nightmare to implement, it probably is a possible way to do it. — Alex Gosselin, Aug 13 '11 at 02:56

score 1 · Accepted Answer · edited May 23 '17 at 12:30

This is definitely tricky. UISearchBar doesn't give you inputAccessoryView and nor do you get selectedRange.
You can paste in a UISearchBar. If you want to get your tricky characters to the pasteboard, you could get a button to execute something such as:
```
[[UIPasteboard generalPasteboard] setString:@"[*]"];
```
and then get the user to use paste in the UISearchBar. Pretty awkward for the user though.
Rooting through the subviews to find the UITextField might work. If you do this, you'd need to grab the existing delegate and make yourself the delegate. Then your delegate would need to transmit messages on. The process is described in this stackoverflow question and answer. Potential challenges here: (a) the Apple implementation could change between iOS updates and even, though unlikely, change the delegate during the lifetime of the UISearchBar; (b) Apple might see this as using a private API and reject the app. (I don't have any hard evidence of (b), but it's something to consider.)
One approach might be to use the bookmark button. The UISearchBar delegate can detect this. You could use that to insert your special characters or offer up a menu of special character insertions. Of course, you won't know where the cursor is. But, depending on your use case, appending the special characters at the end might be OK. Perhaps this doesn't get you anything over a button on your interface that just appends something.
```
[[self searchBar] setText: [NSString stringWithFormat:@"%@[*]", [[self searchBar] text]]].)
```
Implementing your own search bar might be the best way to go as already suggested @hyperbole. I've done this successfully by adding a custom UITextField (with my own magnifying glass in the leftView slot etc.) and adding it as the titleView of my navigationBar. But, if I understand your question aright, that still won't be enough, as UITextField doesn't provide selectedRange and its delegate doesn't provide an equivalent of textViewDidChangeSelection:. You might have a go with a UITextView that is fixed to one line (with scrolling clamped down if required - it often seems to be).

How can I send characters to cursor position of UISearchBar?

Update

2 Answers2