UISearchbar clearButton forces the keyboard to appear
I have a UISearchBar which acts as a live filter for a table view. When the keyboard is dismissed via endEditing:, the query text and the gray circular "clear" button remain. From here, if I tap the gray "clear" button the keyboard reappears as the text is cleared.
How do I prevent this? If the keyboard is not currently open I want that button to clear the text without reopening the keyboard.
There is a protocol method that gets called when I tap the clear button. But sending the UISearchBar a resignFirstResponder message doesn't have any effect on the keyboard.
This is an old question and I just came across the same issue and managed to solve it the following way:
When the searchBar:textDidChange: method of the UISearchBarDelegate gets called because of the user tapping the 'clear' button, the searchBar hasn't become the first responder yet, so we can take advantage of that in order to detect when the user in fact intended to clear the search and not bring focus to the searchBar and/or do something else.
To keep track of that, we need to declare a BOOL ivar in our viewController that is also the searchBar delegate (let's call it shouldBeginEditing ) and set it with an initial value of YES (supposing our viewController class is called SearchViewController):
@interface SearchViewController : UIViewController <UISearchBarDelegate> {
// all of our ivar declarations go here...
BOOL shouldBeginEditing;
....
}
...
@end
@implementation SearchViewController
...
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) {
...
shouldBeginEditing = YES;
}
}
...
@end
Later on, in the UISearchBarDelegate, we implement the searchBar:textDidChange: and searchBarShouldBeginEditing: methods:
- (void)searchBar:(UISearchBar *)bar textDidChange:(NSString *)searchText {
NSLog(@"searchBar:textDidChange: isFirstResponder: %i", [self.searchBar isFirstResponder]);
if(![searchBar isFirstResponder]) {
// user tapped the 'clear' button
shouldBeginEditing = NO;
// do whatever I want to happen when the user clears the search...
}
}
- (BOOL)searchBarShouldBeginEditing:(UISearchBar *)bar {
// reset the shouldBeginEditing BOOL ivar to YES, but first take its value and use it to return it from the method call
BOOL boolToReturn = shouldBeginEditing;
shouldBeginEditing = YES;
return boolToReturn;
}
Basically, that's it.
Best
I've found that resignFirstResponder doesn't work when textDidChange is called from a touch to the "clear button". However, using performSelection: withObject: afterDelay: seems to be an effective workaround:
- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
if ([searchText length] == 0) {
[self performSelector:@selector(hideKeyboardWithSearchBar:) withObject:searchBar afterDelay:0];
}
}
- (void)hideKeyboardWithSearchBar:(UISearchBar *)searchBar
{
[searchBar resignFirstResponder];
}
I found a pretty safe way to know if the clear button has been pressed, and ignore the times when the user just delete the last character of the UISearchBar. Here it is :
- (BOOL)searchBar:(UISearchBar *)searchBar shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
_isRemovingTextWithBackspace = ([searchBar.text stringByReplacingCharactersInRange:range withString:text].length == 0);
return YES;
}
- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
if (searchText.length == 0 && !_isRemovingTextWithBackspace)
{
NSLog(@"Has clicked on clear !");
}
}
Pretty simple and straightforward, isn't it :) ? The only thing to note is that if the user clicks the clear button when editing the UISearchBar's UITextField, you will have two pings, whereas you'll get only one if the user clicks it when it is not being edited.
Edit : I can't test it, but here's the swift version, as per Rotem :
var isRemovingTextWithBackspace = false
func searchBar(searchBar: UISearchBar, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool
{
self.isRemovingTextWithBackspace = (NSString(string: searchBar.text!).stringByReplacingCharactersInRange(range, withString: text).characters.count == 0)
return true
}
func searchBar(searchBar: UISearchBar, textDidChange searchText: String)
{
if searchText.characters.count == 0 && !isRemovingTextWithBackspace
{
NSLog("Has clicked on clear !")
}
}
@Rotem's update (Swift2):
var isRemovingTextWithBackspace = false
func searchBar(searchBar: UISearchBar, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
self.isRemovingTextWithBackspace = (NSString(string: searchBar.text!).stringByReplacingCharactersInRange(range, withString: text).characters.count == 0)
return true
}
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
if searchText.characters.count == 0 && !isRemovingTextWithBackspace {
NSLog("Has clicked on clear!")
}
}
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