When I create a Scrollview on my scene, and then add a button to scene in IB. Then I go into the code, set the content size, enable user interaction and add another button. When I run the program in the simulator the Scrollview does not work, if I remove the button that is in IB on the scene it works just fine. Is it not possible to add items to the scrollview both in IB and programmatically?
EDIT: I thought it may be something in the app I already had. So I decided that I would create anew project and all it has in it is code, and the scene picture below. It is indeed added below the ScrollView.
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[myButton setTitle:#"My Button" forState:UIControlStateNormal];
myButton.frame = CGRectMake(100, 100, 150, 50);
[scrollView addSubview:myButton];
scrollView.userInteractionEnabled = YES;
[scrollView setContentSize:CGSizeMake(320, 1000)];
Here your scrollView is not scrolling due to the autoLayout, uncheck the auto Layout if you are not using.
I Just made a similar to your requirement. It is working fine, and after allowing autoLayout it just stopped scrolling.
The auto layout constraints fits to the visible part of the screen, if the objects in scrollView are more then screen size, it will scroll.
So my suggestion if you are not using autoLayout just uncheck it, and works fine.
Here is an helpful link: http://developer.apple.com/library/ios/#releasenotes/General/RN-iOSSDK-6_0/_index.html#//apple_ref/doc/uid/TP40012166-CH1-SW19
Basically what this says is that, with auto-layout you don't and shouldn't have to use setContentSize:. Instead your inner view should have it's edges snapped to the edges of the scrollview. Let me demonstrate how I solved it.
scrollBackground : a view that contains every other view that needs to scroll in the scrollview.
[scrollview addSubview:scrollBackground];
[scrollview addConstraints:[NSLayoutConstraint
constraintsWithVisualFormat:#"V:|[scrollBackground(1000.0f)]|"
options:0 metrics:nil
views:NSDictionaryOfVariableBindings(scrollBackground)]];
[scrollview addConstraints:[NSLayoutConstraint
constraintsWithVisualFormat:#"H:|[scrollBackground(==scrollview)]|"
options:0 metrics:nil
views:NSDictionaryOfVariableBindings(scrollBackground)]];
The key here being those | at beginning and end of the VisualFormat String. These will tell the scrollview what is the contentSize. Of course if you have a contentSize smaller than the frame size of the scrollview it won't scroll in that direction. In my example this is true for width. It only scrolls up and down.
Make sure you set your content size in viewDidLoad or at some point after the view has already been loaded from the nib file.
As vishy Pointed out, your Button should be part of the ScrollView's Hierarchy, else you'll just be scrolling an empty view.
In the case you posted, the scrollview will not scroll because all of the content is visible. Try changing that last line to:
[scrollView setContentSize:CGSizeMake(50, 50)];
and it will start scrolling, because the content size is smaller than all of the content in the view.
check d2burke answer in this question
you should place your code in viewWillLayoutSubviews instead of viewDidAppear
Related
in some iPhone apps i saw a button which was floating over the content view, eg. in the app EyeEm. When the user is scrolling the content, the button remains where it is and is still an interaction element.
Ho do I implement this?
My approach would be:
Create a view with content
Put a button on it
But how to make the button floating?
edit:
The floating seems to be the default behavior. Interestingly addSubview and insertSubview have the same behavior when placing the button... both are floating over the content.
- (void)addOverlayButton {
UIButton *oButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[oButton addTarget:self
action:#selector(aMethod:)
forControlEvents:UIControlEventTouchDown];
[oButton setTitle:#"Show View" forState:UIControlStateNormal];
oButton.frame = CGRectMake(80.0, 210.0, 160.0, 40.0);
[self.view addSubview:oButton];
//[self.view insertSubview:oButton aboveSubview:_scrollView]; // same result as addSubview.
// Both solutions let the button float over the content.
}
Add a subview to your window's content view with insertSubview:aboveSubview: method with your button and scrollview as arguments, but be careful: if two sibling views both have transparency, the resulting drawing behaviour is undefined.
if you using storyboard just add button over it, like
if you want to do with code insertSubview:buttonView aboveSubview:scrollView
no matters its table or scroll view
So I've seen this question asked a couple times, but haven't come across an answer that solves my problem. Right now I basically have MainMenu.xib with a label centered on the top, a large custom view and a button centered on the bottom that switches subviews of the custom view (see picture below). I've set the window and the custom view to autoresize subviews in the interface builder and all the buttons, labels, etc. have constraints relating them to the sides of the view, but when I resize the window, the contents of the subview do not resize. I think the custom view is resizing with the window because when I switch subviews with the button, the subview that loads is resized with the window, they just aren't resizing with the window in real time.
MainMenu.xib:
Normal subview:
After window is expanded:
Subview switched and then switched back:
CONSTRAINTS:
MainMenu.xib:
BlockViewController.xib:
Figured it out! Really simple, just one line of code in the awakeFromNib method of each ViewController subclass:
[self.view setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
From the pictures and the description in the comments it seems that the problem is that the custom view does not get any layout constraints to determine how to resize the subview.
The following piece of code (typed directly in the browser, so beware) should provide the necessary constraints to "glue" the borders of the subview to the custom view.
[self.customView addSubview: self.blockSubView.view];
self.blockSubView.view.frame = self.customView.bounds;
NSView *blockSubView = self.blockSubView.view;
NSDictionary *viewsDictionary = NSDictionaryOfVariableBindings(blockSubView);
NSArray *constraints = [NSLayoutConstraint constraintsWithVisualFormat:#"|[blockSubView]|"
options:0
metrics:nil
views:viewsDictionary];
constraints = [constraints arrayByAddingObjectsFromArray: [NSLayoutConstraint constraintsWithVisualFormat:#"V|[blockSubView]|"
options:0
metrics:nil
views:viewsDictionary]];
[self.customView addConstraints: constraints];
There is more about this in the docs. Notice the tricks for debugging - very useful to the point of being indispensable.
I have seen many questions in this forum which gives answer to this topic "UIButton inside a UIView, when animated doesn't work", but after having tried out the answers like
a) UIViewAnimationOptionAllowUserInteraction to the options
b) subView.setUserInteractionEnabled = YES
c) [button addTarget:self action:#selector(buttonPressed) forControlEvents:UIControlEventTouchUpInside];
none of them is working for me :-(
Here is the scenario. App is in landscape mode and a UIView called menuView is placed at x=480,y=0. Its height=200 and width=150. So, when I tap the button on the top right corner, the following code is executed
- (IBAction)showMenu {
[menuView setUserInteractionEnabled:YES];
[optionsButton setUserInteractionEnabled:YES];
[UIView animateWithDuration:0.5 delay:0.0 options:UIViewAnimationCurveEaseOut | UIViewAnimationOptionAllowUserInteraction
animations:^{
self.view.frame = CGRectOffset(self.view.frame, 0, 200);
}
completion:NULL];
}
Output?: View is appearing, but optionsButton inside the menuView is not clickable. I hooked up to an event, did an NSLog(#"Options button clicked"), but nothing happens :-(
Please tell me what I am doing wrong?
Update: When I place the subview that is "menuView" inside the self.view, then upon running and click the optionsButton, I get the NSLog message. Only if I specify the origin.x of menuView to be 480 and above, it doesn't work.
If you can see the UIButton, its userInteractionEnabled (YES by default!) is set, and its superview's userInteractionEnabled in the whole hierarchy is YES - you should be able to interact with it.
An animation will never change your userInteractionEnabled property! So what you are doing there is simply unnecessary. If you try to enable interaction during animation - that's a different story and is just an option passed to the animation message.
So if that's not your problem (and is probably not), then I guess one of the superview's frame is cropping the UIButton!
Now you see, if a UIButton (or any UIView) is outside a UIView's frame, it can still be visible, unless clipsToBounds is set on the superview.
And the outcome of that situation is: You can see me, but you can't touch me.
In my case missing a constraint on the height of the containing view caused the view height to be 0. Buttons were visible, below the view, but untouchable.
For me it was all about an overlooked mistake in the animation code itself. Where my new height was being called I was actually calling my new width, and where my new width was being called I was actually calling my new height, therefor causing the UIView to be super long yet super narrow, thus pushing all content within the center of view, outside of the view reach.
Change your UIViews background color to Red so that you can actually see where it animates to.
If your UIView is within another view, turn on clipSubviews so that you only see what is actually enabled within the subView.
Run your project.
If your UIView is not its normal height and width, more than likely you have overlooked some code in your animation call.
Make sure that your x, y, width, height are being shown in the correct orders within the animation code.
In my case, it seems like my animated transitioning is not yet completed. I forgot to to put completeTransition:Bool at the end of my animateTransition:context method.
I have a UIScrollView, with a UIImageView and UIButton inside of it.
I was reading in the answers here that if I have a single view that contains all of my zoomable content, then I should be fine. The problem is that the button doesn't zoom when the image does.
I thought that what I have would work, since the Scroll View is the zoomable view.
Do I need to create another UIView and put everything in there (and keep the same hierarchy?) ?
Have you checked your Springs and Struts? Look in the size inspector under "autosizing". Those little red lines.. if that doesn't make sense, search for 'auto layout'.
I ended up fixing this by declaring the button in code, and added a UView into the hiearchy. The uiview is a subview of the scroll view, and the imageview is a subview of the uiview. I then added the buttons to the uiview.
UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
...
[view addSubview:button];
I have main UIScrollView with lots off buttons which i create like this:
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom]
every button have an image:
UIImage *fileImage = [UIImage imageNamed:#"sun.png"];
[myButton setBackgroundImage:fileImage forState:UIControlStateNormal];
Buttons count could be more than 500. So i need to remove from UIscrollView invisible buttons with images to save memory ?
I believe in this method i need to calculate when UIscrollview is stopped scrolling and for example 20 images are invisible, then i need to remove them and reduce scroller contentOffset.
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
float bottomEdge = scrollView.contentOffset.y + scrollView.frame.size.height;
}
Maybe some one could give me tips on this. Or even have a good bookmarked tutorial.
I created a similar thing to this using UIViews in a UIScrollView. When the UIScrollView loads, I set the contentView size of the scrollView to be the size of all the views but only loaded the views that can be seen, then when the user scrolls i added the previous/next views and removed the hidden views.
This question helped me: How to implement UIScrollView with 1000+ subviews? especially akosma's answer