I'm working on an iPhone game, and trying to use a UIScrollView to display some icons, which I then want to enable the user to drag off the bar being scrolled, onto another view (basically, dragging them from their hand into play on the game board). The problem is that the UIScrollView clips everything outside it's own bounds.
Here is a picture of what I'm trying to do:
Functionally, it actually works, in that you can drag the icons up to the white board fine...but you can't see them as you are dragging...which is not acceptable.
Does anyone know if you can temporarily disable the clipping that a scroll view does, or is there some way to get around it? Hacky or not, I would really like to make it happen.
Does anyone have any other possible solutions for this? Or maybe any alternate approaches? I've considered if maybe a page view might work, but haven't tried it yet...and it's not at all as good of a solution as the scroll view.
Worst case I can just go back to not having the bar scrollable, but that really puts a damper on some of my game mechanics, and I'm really not too excited about that.
I think you're looking for the clipsToBounds property of UIView. I've used it successfully with UIScrollView:
scrollView.clipsToBounds = NO;
However, the dragging you want to do from the scroll view to the game view may require you to remove the icon view from the scroll view, place it in the superview at a position corresponding to its visible position within the scroll view (calculated using the scroll view's origin and content offset), and have that track the user's finger movements. On a release of the touch, either drop it on the game view at the proper position or return it to the scroll view.
I'm not 100% sure I understand the question but I think you should look into the z order of the scrollview and the whiteboard. It may be that the drag is just going behind the whiteboard.
Failing that, it would be useful to see all the bounds of your view heirarchy.
I also think a better solution allround might be to create a "sprite" to animate underneath the players finger - you could offset the drawpoint of the sprite from the touchlocation so that the player can see what they are dragging.
Related
I have a paged scroll view in my app and it works almost perfectly... Usually one page looks like this:
There is no content below this, but when i move it as if it should scroll down (clicking and swiping upwards) it stops moving at this stage:
It's as if its decided that that is an acceptable page loaction or something. If i drag it part way up it snaps the rest of the way up, and if i drag it part way down it snaps all the way down.
Why is it considering this an acceptable place to stop? Is there an easy property to set im missing? Or is there a way to allow only horizontal scrolling?
Thanks
Check the contentSize property of the scroll view. That determines how far it will scroll, and you can manually set it to control exactly where it will scroll to.
Is the scroll view on 0,0 on the canvas? It looks like it is not actually centered on the screen.
I know that I asked a question a few minutes ago, but I want to make a few points clearer before asking for the community's help. I'm new to iOS development, close to finishing my first app. The only thing standing in my way is this UIScrollView. I simply do not understand it, and could use your help.
This is in the detail view controller of a drill-down app with a tab bar. I have approximately 8 fields (for things like phone numbers and such) drawing from a .plist. Obviously, those take up enough room that I could use a little extra real estate. I would guess that it needs to be about the size of two views vertically, but I do not understand how to allocate that sort of space to a UIScrollView. Some tutorials I have read say that you don't even need to define it in the header, which I doubt and do not understand. Additionally, I do not understand how to simply get the app to smoothly scroll up-and down only. Apple's examples have constant move cycles that flip between horizontal pictures.
I doubt it makes very much a difference, but I have an image that is in the background. I'm going to load the view on top of that.
My question is broad, so I don't expect you to take the time to sit down and write out all of the code for me (and I wouldn't ask you to). Just an outline of quick, helpful tips would help me understand how to get this view to load in the context of my project.
Many thanks!
It's fairly simple. Add a UIScrollView to your view. Add your fields and such to the scrollview. In viewDidLoad or somewhere similar, you need to set the contentSize on your scrollview. This is the "virtual" area that will be scrollable. This will generally be larger than the frame of the scrollview. In your case, you indicated it should be roughly double the width.
For instance, if you had a scrollview with a view inside, and you wanted to make sure the entire view is visible via scrolling:
self.scrollView.contentSize = self.contentView.frame.size;
//setting scrollview zoom level
self._scrollview.minimumZoomScale=0.5;
self._scrollview.maximumZoomScale=6.0;
self._scrollview.contentSize=CGSizeMake(320,500 );
you have to outlet scroll view in .h class and #property #synthesis this scroll view.then you can able to scroll up and down,if u want only vertical scrolling ,then u have to go to interface builder and uncheck the horizontal scrolling.
You can set a few settings for your scrollview to limit the scrolling to horizontal or vertical. A few important ones are:
// pseudcode here, start typing "[scrollView " then press escape to get a intelli-sense of all // the things you can set for the scrollview.
// values could be YES/NO or TRUE/FALSE, I can't remember which one but
// I think it's YES/NO. Once you start scrolling, the phone will determine
// which way you're scrolling then lock it to that direction
[scrollView setDirectionalLockEnabled:YES];
// when you slide the view, if enough of the next part of the view is visible,
// the scrollview will snap or bounce the scrollview to fit this new "page".
// think of swiping feature to navigate the iPhone home screens
// to show different "pages" of iphone apps
[scrollView setPagingEnabled:YES];
// as a safe guard, make sure the width of your scrollview fits snuggly with the content
// it is trying to display. If the width is more than necessary to display your table of
// data vertically, sometimes the scrollview will cause the
// horizontal scrolling that you don't want to happen and you get bi-directional scrolling
Just set the content size of UIScrollView after adding all the controls/button/textfields etc. for example you add 10 textfields in UIScrollview then content size of UIScrollView will be
lastTextField.frame.origin.y+lastTextField.frame.size.height+20; 20 is for margin.
That's it let me know if you want to know something more related to your app.
Ok, I have a complicated scenario here. I have a scrollview which scrolls horizontally and contains tiles, 1 centered on the screen at a time with the user still able to see if there are more to the left or right by way of having the edges of the 2 views visible on either side. I am able to add the views programmatically to the scrollview and have paging work properly, so the user can swipe back and forth between them. Another requirement is to have an initial animation where the first view slides in, then is bounced off to the left by the second view. I accomplished this by using a series of UIView animations, and it works well.
Here is my problem: After the animation completes, you cannot scroll left to get to the first UIView that was created. I suspect that this is because it was animated out to the left of the content area of the scrollview. I have tried to increase the contentSize of the scrollview, but I still get the same behavior.Once the initial scrollview has been moved off to the left, I cannot swipe to page to it.
Is there a common pattern I could use to accomplish this in a better way?
It sounds to me like you're animating the child view's frame to the left so that the x coordinate of that first view's frame is negative, instead of animating the scroll view's contentOffset to the right. If that's the case, is there a reason you aren't just setting the scroll view's contentOffset inside an animation block? If there is a reason, what if after the animation completes you "fix up" the content offset and the frames of the child views so that none of the views are in a negative position.
But, I guess I have more questions than answers right now, so it might help to post the code showing how you do your animations to make it easier to answer your question.
Client wants some tricky stuff and i don't really know where to start with it.
The idea is that there is a horizontal scrollView whose each page consists of a vertical scrollView.
For example, on the horizontal axis there are galleries, on the vertical we scroll through selected gallery's images. Is this even possible?
I'd be very glad to hear comments on this one!
You will have to manage the state yourself. When one scrollbar is selected the other has to be disabled and vice versa. You can also disable the user scrolling and handle the swiping yourself with the touch events. (on a clearColor UIView as a topmost view).
They all works magically, there's no additional work for this unless there's an issue about memory consumption which will require more coding.
Simply, create a horizontal scroll view then add vertical scroll views into it. Don't forget to update the contentSize property.
This is probably either real easy, real dumb, or my google fu has taken a serious turn for the worse. Anyway, I'm implementing custom view for my app, which is using pure CGContext drawing, no subviews (for now at least). The thing is, I want it to autorotate, so I have shouldAutorotateToInterfaceOrientation return YES, and voila, the view rotates. But in doing so it's not actually redrawing the content (which I assume is rendered into a texture somewhere in the framework and splashed onto a rect, but that's not really relevant here), the rect is simply stretched, squishing the content. How can I get it to simply issue a draw of a bigger area while rotating? That is, my content is bigger than the screen, and I'd simply like the viewport to change during the rotation.
I've tried setting the view's contentMode to UIViewContentModeRedraw, but that didn't do anything, I've tried playing around with the autoresizeMask stuff, but didn't seem to help either. I've also tried inserting a setNeedsDisplay in willRotateToInterfaceOrientation, however that only caused it to redraw using the new bounds (i.e. squishing it first, and then stretching it out to the right size during the rotation), which is also not what I'd like to see.
Does anyone have any idea how I might go about getting this to work?
As it turns out, it's a mix of dumb and easy. I'm posting it here if anyone should care to read it someday. They way I managed to solve it was actually sandwiching a view between window and my view (I suppose you might be able to go to work on the window directly, but it felt more intuitive this way). That is, I added my view as a child view to that view, which I'll call the frame.
The frame is a resizing as normal, however, I turn OFF resizing of child views, and make my own view LARGER than the viewing area (square actually, 480x480, so it can cover the entire screen either way). Problem solved, basically.
Now I'm playing around with animating the offset of the view in the frame during willRotateToInterfaceOrientation, to have it appear to be rotating around the center, rather than the upper left corner, but that's a different question.