UITextField shouldBeginEditing called every other time? - ios

Question

iOS unfortunately doesn't have a dropdown picker like html does with the tag. I decided that I was finally going to create one for my app, and it looks and works great. My dropdown object is a subclass of UITextField. However, I changed something and now it only works some of the time.
User interaction is enabled, but I don't want the textfield to be editable. The class in which my dropdown subclass resides is UITextField delegate, and should receive delegate methods for UITextField.
I have - (BOOL)textFieldShouldBeginEditing:(UITextField *)textField{ where I check to see if the textfield in question is a dropdown menu, and if it is, I call a method to instantiate a popover and disable editing, but the dropdown only appears on every other tap.
For example, i'll tap the "textfield" and my popover displays. I tap out so the popover goes away, then I tap on the "textfield" and nothing happens. I tap on the textfield once again and the popover appears. No idea why this is happening, here is what i'm doing:
.h
subclass : UIViewController<UITextFieldDelegate>
.m
dropdownTextField.delegate = self;
...
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField{
if(textField == self.measurementSelect){
NSLog(#"IM CALLED");
[self showPopover:textField];
return NO;
}
return YES;
}
-(void)showPopover:(id)sender{
if (_measurementPicker == nil) {
_measurementPicker = [[iPadMeasurementSelect alloc] initWithStyle:UITableViewStylePlain];
_measurementPicker.delegate = self;
}
if (_measurementPopover == nil) {
_measurementPopover = [[UIPopoverController alloc] initWithContentViewController:_measurementPicker];
[_measurementPopover presentPopoverFromRect:self.measurementSelect.frame inView:self.conversionView permittedArrowDirections:UIPopoverArrowDirectionLeft animated:YES];
}
else {
[_measurementPopover dismissPopoverAnimated:YES];
_measurementPopover = nil;
}
}
Every tap gets nslogged, so I assume my popover method is the culprit of this problem. Any ideas?

Answer 1

Let's rewrite by teasing apart existence of the UI elements and the visible state of the popover:
// canonical lazy getters for UI elements
- (iPadMeasurementSelect *)measurementPicker {
if (!_measurementPicker) {
_measurementPicker = [[iPadMeasurementSelect alloc] initWithStyle:UITableViewStylePlain];
_measurementPicker.delegate = self;
}
return _measurementPicker;
}
- (UIPopoverController *)measurementPopover {
if (!_measurementPopover) {
_measurementPopover = [[UIPopoverController alloc] initWithContentViewController:self.measurementPicker];
}
return _measurementPopover;
}
// now the show/hide method makes sense. it can take a bool about whether to show or hide
-(void)showPopover:(BOOL)show {
if (show) {
[self.measurementPopover presentPopoverFromRect:self.measurementSelect.frame inView:self.conversionView permittedArrowDirections:UIPopoverArrowDirectionLeft animated:YES];
} else {
[self.measurementPopover dismissPopoverAnimated:NO];
// if you want/need to create a new one each time it is shown, nil the popover here, like this:
// self.measurementPopover = nil;
}
}
When the textField begins editing, show the popover like this:
[self showPopover:YES];
And when the delegate gets the didEndEditing message:
[self showPopover:NO];