I have got some special buttons(implemented with the subtype OBShapedButton, the button can have an transparent image and is only clickable on the size of the image) on my view. Now I have the idea to touch on the screen and move around. Everytime when I move over one of my buttons, I want to do something. How can I do that? I tried with the LongpressGestureRecognizer, but I dont know how I can get the objects I touch during the movement of my finger.
Any ideas?
Go take a look at UIControlEventTouchDragEnter in the documentation.
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I am making an iOS app for remote controlling the lights in my house. I have a list of groups of bulbs (rooms) that can be turned on and off. My problem is selecting a room, I want it to be like this:
You can either press the arrows left or right to switch the room, or you can put your finger, where it says Living Room and swipe left or right to switch it.
Can someone give me a pointer as how to implement a swipe feature like that? I know there are gesture recognizers. I never used them, but I guess they won't automatically make the text I want to swipe follow my finger.
I guess it would be possible to use the gesture recognizer and manually move the text to get the swipe "feeling". It just seems to me like there should be an easier solution.
I've done something similar several times, and the most elementary way to approach it is to override the touches... methods on NSResponder. This will tell you when a user's finger touches the component, when it moves, and when they let go. From that, it's pretty easy to adjust the position of your UIView, do some custom rendering, or whatever else you need.
Another, higher-level, approach is to use a UIScrollView and implement it's delegate methods. Inside the scroll view are three elements which completely fill the viewport: the one you can see, and those to the left and right. You watch the delegate events for the user adjusting the position of the viewport and as they expose an element to the left or right, you can snap the viewport into place when they let go. Then, you adjust the three inner views to show the appropriate new content and reset the viewport to expose the middle element (which would then be showing the appropriate content).
There are undoubtedly many other approaches, but I've used both of these with good effect.
I solved it in the end by using a pangesturerecgonizer attached to the label. It's pretty straight forward, I just didn't know pan is supposed to mean something like drag and drop, I thought pan would be something completely different.
I've scoured the internet and I cannot seem to find any help on this. I want to have an image perform a wipe animation. By that I mean I would like the image itself to fade in from the left to right (not move from left to right, but fade, like reveal itself. I hope that's not a terrible description) I've found material on how to transition the image with a wipe, but it's outdated and I don't want to transition the image, I want to straight up fade it in. If anybody could help me on this I would be incredible grateful. Thank you so much, let me know if I can help clarify anything!
First thing that came to my mind is to have a separate UIImageView, with image something like this: http://www.creativecow.net/articles/ahearn_luke/creating_clouds/images/gradient.jpg (but transparent-to-white).
So - once You want to fade out Your image, You add as a subview a new UIImageView, which has frame like 3 times the width of the original image You want to hide. Once You add it as a subview, visually nothing would change, as the beginning of the hovering UIImageView would be transparent, But then You start animate frame (origin.x) of the hovering UIImageView so that it would be moved to the left side. While this happens, bottom ImageView will be gradually hidden from one side. After animation ends, You remove/hide both UIImageViews.
Not the best solution, but - if You are stuck, and still want the effect... Atleast some option.. Good luck!
I am displaying hundreds of thumbnails in my view . I know default way to handle tap on thumbnail is using UICollectionView delegate method "didSelectItemAtIndexPath" but since its many thumbnails i wanted to look into adding gestures to the screen position so when i tap on a particular spot on the screen, it will handle the event accordingly for that particular thumbnail underneath. I would like to know if it is a good/possible approach?
It would be a hell of a lot easier to use a UICollectionView.
If you need a custom layout then you can subclass UICollectionViewLayout and get some really cool dynamic layouts.
You also get the added bonus of dequeued cells meaning that you get better memory management using it.
You may find UIGestureRecognizer useful. A good tutorial to get you started is here.
I am trying to make an irregular shaped button with the OBShapedButton class. That's ok, created it without any problem, however I need the image to be transparent. So, I just want an area from the image which will be clickable, but the image won't be seen.
I tried setting alphas on image, imageView and on the button itself, however it doesn't work neither way.
How should I do it?
Maybe it could be done by something else, not an UIButton, but unfortunately I didn't find anything on the net that I could understand and use.
Ok, so the easiest way on how to do this is:
Subclass UIButton and add touchesBegan, touchesEnded, touchesMoved,
touchesCancelled.
Then on touchesBegan, hide the image of the button and show the correct image in background.
And finally on touchesEnded or touchesMoved, show again the image of the button.
Hope it will help someone :)
I have some views that start off the screen and then slide in and out at various times. In IB, the x,y positions are off the screen, because that is where I want them to start.
Now, I could just put them anywhere in the x,y space in IB and have the viewController's viewDidLoad method move them off the screen initially.
My question is, since they are currently off the screen in IB, is there an easy way to access and edit them in IB without changing the x,y position of a view first so that it appears on the screen in IB? Because I am editing these views fairly often.
If there isn't, then I'll probably just position them anywhere in the visible space in IB and add some stuff to viewDidLoad to get them out of the way. Or any other suggestions I'd love to hear.
If it's a separate view, just drag it to where you want it, and double click it's name in the objects list as seen in edo42's answer. You could also figure out the final x/y coordinates and set those with your code, and just move the view wherever is convinient.
You click there
and then select your view here