Take a look at this method:
[textButton addTarget:self action:#selector(articleModalWillAppear:) forControlEvents:UIControlEventTouchDown];
When the button is touched, it calls articleModalWillAppear:. That works well. The problem is the button also calls the action when it is dragged. (The button is big and contains a text paragraph)
I put six such buttons as subviews of UIScrollView (with UIPageControl). It works well when dragging UIScrollView horizontally. But it pops up modal views when dragging vertically because when a finger dragging across a button, the button considers it as a touch, and the touch calls articleModalWillAppear:.
If you still don't understand my problem, think about the New York Times iPad app. You can drag the pages horizontally. You can touch an article description to go to the full article view. But nothing happens when you drag vertically inside an article description. How to achieve this?
Use a different event e.g.:
[textButton addTarget:self action:#selector(articleModalWillAppear:) forControlEvents:UIControlEventTouchUpInside];
UIControlEventTouchUpInside is the most generally used in this case.
use forControlEvents:UIControlEventTouchUpInside
That only registers a click event when a user touches down inside the button and then touches up in the same button, and ignores drags.
Related
I have a toolbar with 5 buttons.
4 of them are regular bar button items and one of them is a custom one (A 'UIButton' inside a 'UIBarButtonItem').
I noticed that when I click between the regular buttons (not exactly on them), one of them (the closest one) still recieves the click event and is being highlighted (which is what I want).
But the custom bar button item does not show this behaviour.
When I tap between it and one of the regular buttons neither of the 2 receives the touch event. This probably because the UIButton is the one the gets the click event. Is there a way to add a touch event the containing bar button item as well? Or perhaps another way to solve this?
Thanks!
button.userInteractionEnabled = YES; I believe is the answer.
One solution might be that you create image of same as bar button item and assign to UIButton as background image, this will solve your issue.
Hope this helps you....
Solved it!
I added another UIView to the UIBarButtonItem and then I added the UIButton to the UIView.
I added a touch gesture to the UIView (And also kept the original touch event of the UIButton) that expanded the area that you can touch the button which solved the problem.
I am creating a semi-piano app in Objective-C for iPhone; it's in fact a diffrent layout MIDI Controller, but I'm still working on the design.
I created all of the "keys" with UIButtons, and I want to be able to slide to them or from them to other UIButtons.
I read all the similar questions before, but I couldn't make it to work with touchesMoved,
Because it only worked from the view if I didn't drag the finger from a UIButton.
Thanks in advance, code will be appreciated!
Are your buttons created in IB? The default event when connecting buttons in IB is "touch up inside", which means the action is fired when the user ends a touch (lifts the finger) inside the button. A piano key or similar would be more appropriate to fire on the "touch down inside" (for the initial press) and the "touch drag enter" (for when a finger that is already on the screen moves into the button).
Since you are doing it programmatically, you can add targets to the buttons as described here:
http://developer.apple.com/library/ios/documentation/uikit/reference/UIControl_Class/Reference/Reference.html#//apple_ref/occ/instm/UIControl/addTarget:action:forControlEvents:
Just include the events you want in the mask.
In my app i want to open a view with the content of a particular button (so that button should look clicked and should be not clickable). I have 4 button with pictures and all the four have different content inside them (Table view with different content).When this view gets open i want the first button clicked automatically and the content of that button should get displayed and by clicking any other button the content of that button should get displayed and the previous clicked button should be available to click again.
I am using different pictures for clicked and unclicked button.
Thanks,
Maybe this will help you
- (void)didClickButton:(id)sender {
UIButton *optionButton = (UIButton *)sender;
if(lastSelectedButton.tag!= optionButton.tag) {
optionButton.selected = YES;
//According to your needs enable or disable the button's interaction
}
Here lastSelectedButton should be an instance variable.
What you're describing sounds like a segmented control. Essentially the segmented control works like buttons on a tape recorder (dating myself, I know.) When you press Play, it stays down and can't be pressed again until you press Stop or FF or Rew, etc. (Ok, Stop doesn't really work that way, but the rest of the buttons do)
Unfortunately, I don't believe you can use your own images in a UISegmentedControl, but fortunately there's an open-source version that should work for you: https://github.com/xhan/PlutoLand/blob/master/PLSegmentView.h
Once you have the control in place you can change the content of your main view depending on the value of the segmented control. You can handle that in the UIControlEventValueChanged event
Keep a single selector for all the buttons something like
[btn addTarget:self action:#selector(templateSelected:) forControlEvents:UIControlEventTouchUpInside];
and make use of the tag to carry any index to the selector
[btn setTag:integer];
and if you want to keep track of previously clicked button then keep a global (id) and assign the current button address to the that id.
And if you want the first button to be clicked on load then call the function melodramatically during initialization of the first button.
[self templateSelected:firstButton];
I have a UIButton subview inside of a UITableViewCell.
When this button is touched, the user must hold the button for about a half second for the button's image to change to the UIControlStateHighlighted image.
This means that if the user just taps the button as is usually the case, the highlighted state is never shown.
Why does this occur and how can I fix it?
I just encountered this problem and saw that this issue hadn't been closed. After screwing around for a while I found a fix for it.
Now you can fix this by turning off delaysContentTouches or unchecking the "Delays content touches" box on the tableview.
The only negative side effect is that the user won't be able to tap down on a button and initiate a scrolling gesture. However, if the user tries to scroll starting from anywhere that doesn't itself accept touches, the behavior should be the same as before.
The problem is that your UIButton is inside a UITableView. This means that the table view has to determine whether your tap is going to be a swipe or if it's just a tap intended for the button. The table view has to delay sending a message to the UIButton until it knows that the user doesn't intend to swipe and therefore scroll the view instead of pressing the button.
If you don't need a table view, get rid of the UITableView.
Up for David Hodge's answer.
I just want to add a way to remove that "only negative side effect", already described by David: if you start scrolling inside a UIcontrol in a UIScrollView with delayContentTouches=NO, scrolling doesn't work.
SOLUTION
Subclass UIScrollView (or UITableView as the original question) and override:
-(BOOL) touchesShouldCancelInContentView:(UIView *)view {
return YES;
}
Your UIControls inside UIScrollView/UITableView will change their state immediately on tap and the scrollviews will be able to scroll even if the touch starts on some UIControl. Works like a charm.
I just change the image from within the target action method:
[sender setBackgroundImage:[UIImage imageNamed:#"highlighted-image.png"] forState:UIControlStateNormal];
It changes the background image instantly.
Edit: completely re-written following a misunderstanding of the question
One way of thinking of a UIButton is as a shorthand way of setting up an area of the screen that can respond to various instantaneous touch events the response it makes is defined by UIControl's Target-Action system for delivering messages to other objects.
UIControlEventTouchDown sounds like the one you need to respond to. It will be triggered as soon as someone touches inside your button - this is what the "Contact Info" button in SMS does.
UIButton* myButton = [[UIButton buttonWithType:UIButtonTypeRoundedRect];
// SEt up title, frame etc
[myButton addTarget:self action:#selector(myButtonWasPressed) forControlEvents: UIControlEventTouchDown];
[myMainView addSubView:myButton];
Will send a -(void)myButtonWasPressed message to the object this code runs from (ideally you view controller). In myButtonWasPressed you can then add a new view or take any action you like. The SMS app pushes a view controller to display the contact info using a navigation controller.
If this still doesn't solve your problem, you're going to have to post some code in order to get more insight into what's going wrong.
when i am pressing my UIButton ,(i did not release my mouse button),i want to change
title? i tried touchupinside through XIB.but it was called after i released my mouse button.
i tried both land also all states....?
[sButton setTitle:#"hai" forState:UIControlStateNormal];
[sButton setTitle:#"hai" forState:UIControlStateHighlighted];
The Control Events documentation will list all of the events you can subscribe to for controls (in this case, your UIButton). The one you want is UIControlEventTouchDown. But the problem with your requirement is that pushing the button covers the screen with the user's finger and I wonder whether changing the title will really be beneficial.