iOS drag and drop images - ios

I was trying show a bunch of images, one at once. User could swipe left or right to navigate, just like photo library.
What I did is, for example I have 6 images, create a scroll view to hold those 6 images, and using pan gesture to move it.
Am I doing right? Or is there another neat solution?
Thanks
EDIT:
I'm asking am I doing right by using gesture?
More specific, should I use UIScrollView to do this or I should use something else?
Update:
I finally figure out a way to do. Use UIPanGestureRecognizer and check the speed. if the speed is fast enough, then treat like swipe gesture. Will post code later.

UIScrollView has a default gesture and does not need a new one.

Related

ios voiceover slider double tap and hold, but for custom view

I've created a custom view that acts like a UISlider - there is a "track", and a handle to "grab" to change the value. For particular reasons, I can't just make it a subclass of UISlider. I'm trying to make this slider as accessible as possible with VoiceOver. I have accessibilityIncrease and accessibilityDecrease on my custom view that handle single finger drag up and single finger drag down. This changes the value of the slider by 10% at a time.
However, I'd like to allow more fine grained control, just like a non-VoiceOver slider. By default , UISlider has double tap and hold, and you can drag up/down to "pan" the slider. I'd like to add exactly that to my custom view, but I can't find the correct incantation to handle the double tap and hold gesture.
Is there something I can do to mimic the double tap and hold gesture from UISlider on my custom view?
Thanks very much!!!
If you want to implement this kind of new gesture for VoiceOver users, just forget it.
The recommended gesture for this kind of UI control is definitely the implementation of adjustable value as you already did apparently.
I don't think it's a good idea to try and implement new VoiceOver gestures in an application because its users have their habits and they may be totally lost with your customed control if they cannot handle it unless you add an hint to explain but that's definitely not what I recommend anyway.
Otherwise, you could take a look at the pass through concept introduced in the What's New in Accessibility WWDC 2017 video that deals with the same idea but for a panning gesture...

Pan speed calculation to perform different tasks in swift

I have a set of objects in a UIScrollView that I am able to do the pan gesture. However, I would like to be able to scroll the view if i'm doing a swipe even if i hold the object and swipe too fast. Is it possible for me to calculate the speed of the drag and drop so i can make the UIScrollView move instead of executing a drag and drop of the swipe is fast?
What would be the solution for this? Please advise
There may be a simpler way. You can ask a gesture recognizer to wait for another to fail before starting. It seems to me that it is what you want to achieve. Can you try :
[scrollView.panGestureRecognizer requireGestureRecognizerToFail:myGestureRecognizer];
or the other way
[myGestureRecognizer requireGestureRecognizerToFail:scrollView.panGestureRecognizer];

Autoscrolling in a UIScrollview

I have been only using Xcode 5 for a little while now and I need help when it comes to auto scrolling a UIScrollView. I am using a single view application. I need the screen to scroll down at a pace that speeds up incrementally. Also I need the screen to keep progressing even when the screen is touched. If someone can explain which code goes where it would be great! Your help will be greatly appreciated. :)
Check out this library: https://github.com/danielamitay/DAAutoScroll
It stops to scroll when the user touches the screen and that's the only solution I see possible. I don't even see why you wouldn't want the user to be able to stop the scrolling..
OK, just adding this from your duplicate question.
I suspect the Piano Tiles game is actually using something like Sprite Kit.
This allows a lot more control over thing like "scrolling" speed.
Instead of using a UIScrollView you would use an SKNode as a layer with the buttons added to that parent layer.
Then using the update game loop you can incrementally increase the speed of the movement based on the time since the game started.
In essence... don't use UIScrollView, don't use UIKit, use SpriteKit.
I can see a few options:
1) suggested by Fogmeister, use Sprite Kit instead.
2) see setContentOffset
3) just use a normal view as parent, then have another child view on top with the full content (would be longer than the parent view), create a NSTimer to periodically call a method which scrolls the child view in whatever direction and speed as required.
Note that might need something on top to mask around the child view from showing the suppose-to-be-hidden sections of the child view.
Hope this helps

Dragging an uiview like facebooks menu slide

I know this has been probably asked before but I've seen many approaches and i don't know which is best for me, so plz don't send me a link to another post unless it addresses my problem directly.
I have a controller which has a uiview on the top (like a header) (this header is bigger than it seems because is partially hidden on top). on that view i have a uibutton which now with a touch up inside shows the entire header view and taping again returns it to its starting position (changing frame with animation). I want to also be able to drag the view but only changing position on the y axis(dragging up and down)... i was thinking of adding the dragInside/Outside event to the button but this doesn't give me the position of the finger... and also want to know when the user releases the drag so the view ends animation to any of its two possible states (showing or partially hidden). Is this a "touches began" , "touches moved" , "touches ended" thing? if it is please provide a code example. I also want to do this with another view but this is on the left side... same thing but this one moves on the X axis... any help is appreciated. or maybe it can be made with drag event if i only can save a CGpoint of last touch, maybe that's better, any other suggestions
Look at using a UIPanGestureRecognizer to detect the touch movements. Use the translationInView: of the gesture to set the view y position. The translation is the total movement since the start of the gesture so you don't need to remember and accumulate the offset position yourself.
The main thing to worry about while implementing this is bounding the y position of the view so that no matter how far the user drags the view won't go too high or low on the screen.
Use a UIPanGestureRecognizer, that's a class dedicated to handling such drag/pan gestures.
Everything is described here in Apple's documentation, including examples, so you should find your answer here.
There is also some sample code in Apple Developer Library that shows you how to use Gesture Recognizers if needed.

How to make SWTableViewCell swipe more sticky

I've implemented the SWTableViewCell code in order to allow side swipes to reveal more UI, such as buttons.
Which is working fine, except that the UIScrollview it subclasses is really just too touchy, flicking back and forth like a manic game of ping pong.
I went to make changes to the class, but realised UIScrollView didn't seem to give me the ability to say change the way the scrolling animations work in the way I wanted.
Leaving me thinking that I either need to create my own version of the a Swipe cell, with a pan gesture and a overlay view, instead of a scrollview or find someone who has already solved this problem.
Please check it out sample: https://github.com/runmad/RMSwipeTableViewCell
May be it will helpful to you, Sir
:)
Not sure if this will give you the effect you desire, but you can make it less "jumpy" by altering the decelerationRate. Try:
someScrollView.decelerationRate = UIScrollViewDecelerationRateFast;
If that's the right idea, you can jump-to-definition in Xcode, and checkout the float value, then try your own.

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