I am following this excellent small tutorial about drawing on screen in the layer of a UIView (subclass).
http://spritebandits.wordpress.com/
It just works.
There is just one thing. I placed this view as subview of a UITableViewCell which, naturally, is displayed as part of a UITableView.
I guess I would have the same issue when I would place it within an UIScrollView. (UITableView inherits from UIScrollView anyway)
Touches are triggered by my painting view as long as their related movement is horizontal. As soon as I move the finger kinda vertical, even partly, then the UITableView takes over and scrolls the table.
Is there any proper way of stopping the Table to taike control of the touches while the touch is actually within my view?
If it is of importance: I am using storyboard. The cell is a prototype cell with its own subclass of UITableViewCell.
I've implemented this using the same class "Canvas" you're saying and also inside a UITableViewCell. But I didn't use the entire cell for drawing, only a UIView inside of the UITableView as a subview.
I reached the whole user experience by activating and deactivating the UITableView scrolling when that UIView (subview of the cell where I allow the drawing) fires touchesBegan or touchesEnded. So when they touch/move inside the UIView, they're drawing. When it's outside, they're scrolling. So they can't scroll on the UIView because they will be drawing.
The problem in your case is that since the whole cell is the view for drawing, the user cannot scroll in this concrete cell because it's the drawing one.
Hope this will help.
I dont have an answer for that. But there is essentially a work around.
You could get the user in to a drawing mode, where the scrolling for a UItableviewcell is disabled and then
once the user is done with drawing, you could enable scrolling again.
Inclusion of a button anywhere on the screen would help you switch modes.
Related
When I initiate movement for my collectionView cells, the cells do not move. They move only when I pan my finger over another cell. So if I initiate a movement by pressing one of my cells and then pan, the cells do not track my finger. The only time animation occurs is when my finger pans over another cell. At that point the animation is just the reordering. Bonus: One I end my gesture (lift up my finger) the current cell I was moving around disappears from view. I am using a custom flow layout
My custom flowLayout is stopping the animation. In my custom layout I set the frames of my cells (their attribute frames) to a specific position that is hardcoded in my layout. When the long press gesture is initiated I have to change my attributes somehow.
You don't need to update your attributes. Just make sure you are overriding these methods in your custom layout:
layoutAttributesForElements
layoutAttributesForItem
layoutAttributesForSupplementaryView
I was being able to move my tableViewCells just fine until I added a UIView as subView of my UITableViewCell. The width of this subView is the same of my cell. This means it covers it completely. This subView is in fact transparent enough for the grabber control to be seen even though it is over it.
I understand I am not being able to move the cells to reorder them because the view that I put over my tableViewCell is covering it completely and is over the grabber control and is not letting the grabber control detect the pan gesture.
Is it possible somehow for my views to detect this pan gesture and pass it on to the grabber control so that I can reorder the cells?
If not, is it possible to do this cell moving and reorder manually? (Having my own cell grabber control over my tableView).
Some objective C snippet will be much appreciated.
I am using a UIView subclass which can be resized by dragging on the borders and it is added as subview on a UIScrollView. I am also using a UIGestureRecognizer subclass to move the view on the UIScrollView such that the custom view remains visible and the scrollview autoscrolls.
This setup is working as intended but for one problem. Whenever the custom view is resized, the touches on UIScrollView are lost, i.e the scrollview does not recognise the tap or scroll on it unless the custom view is tapped or dragged once again. I have found that after resizing, neither custom UIView nor custom UIGestureRecognizer's touches began, cancelled or ended are called.
Where might the problem be?
I have UIScrollView with other UIView elements inside. My other UIView elements are mostly segmented controls. If I click on a UISegmentedControl and hold for a second and then try to scroll, then no scrolling happens. I can only scroll when my finger touches and swipes immediately. I checked other iOS applications such as mail. The behavior was that you touch and hold on a mail, then it's highlighted, but as soon as finger moves away, the scrolling happens and highlighting is undone. How can I implement this behavior?
The issue was the property of UIScrollView. The property canCancelContentTouches was set to NO. Because of that, touch events were handled by subviews of scroll view and swiping didn't cause scrolling.
You can follow one of these steps:
If you are using UISegmentedControl over you UIScrollView, instead of that, add the UISegmentedControl over your controller's view.
If you want to use UISegmentedControl over your scrollView, then you have to create a custom scrollView by creating a subclass of UIScrollView and use an image view instead of UISegmentedControl adding the labels which can act as the segments. This is because your UISegmentControl itself is a touch handler and it breaks the UIResponder chain. So, the scrolling might face issues during the touch events.
Please let me know if any of these works. Thanks :)
I have a UITableView and would like to have a custom way to delete my cells. When someone swipe on it, the cell would move horizontally on the side and disappear.
Exactly like the multitasking menu on iOS 7 (http://movies.apple.com/media/us/ios/ios7/f34c5445-5a9c-4b3a-9556-8efe89147559/shared_multitasking/shared_multitasking_2x.mp4), but instead of swiping vertically, it would be horizontal.
Does any one knows how to do that? Should I just detect a swipe and change the frame of my cell with a 1 sec animation? Or are there nice subclasses of UITableViewCell you would recommend?
I just threw together a very basic example of how to do this and posted it here: https://github.com/NSPostWhenIdle/MMSwipeToDeleteCollection. Don't expect to be able to drag and drop this into your project and have it work, because quite frankly it probably won't.
The basic idea to create something like this starts with a subclass of UICollectionViewCell that adds a gesture to the cell. In my example, I used a swipe gesture because I'm lazy :p and there is more overhead involved in setting up a pan gesture (which you'll want in your end product) because there is conflict between that pan gesture, and the pan gesture in the collection view's scroll view.
From there it's basically smooth sailing. When the gesture recognizer gets called you animate the cell out the top of the screen. If you set this up with a pan gesture, you'll need to configure this to drag the cell, and animate up or down upon completion, but in my swiping example, the cell moves to just out the top (of the 4 inch simulator, I used static values).
Then all that's left to do is some clean up. Once the cell has exited the screen you can safely delete it from your datasource and then from the collection view. (I used notification center do alert the collection view, but you should probably make a protocol) The only issue I had with this was that the cell animated back down while fading out as part of the stock deletion animation. Setting its alpha to 0 after it leaves the screen solves this problem.