I'm not really sure why this isn't working, hopefully you can help me find the missing piece. I have a UIScrollView with paging enabled. I'm using it for side-scrolling through a tutorial. I have a button that when tapped should scroll the user back to the beginning of the tutorial. I originally tried using the scroll view's frame as the rect to scroll to because that CGRect should represent the first page. I've tried a couple of different CGRects to no avail though.
- (IBAction) touchedButtonReturnToBeginning:(id)sender {
// I've tried several CGRect's, none of which cause the UIScrollView to move.
// CGRect beginning = self.containerScrollView.frame
// CGRect beginning = self.containerScrollView.bounds;
CGRect beginning = CGRectMake(0, 44, 1, 1);
[self.containerScrollView scrollRectToVisible:beginning animated:YES];
}
I have verified that self.containerScrollView is hooked up in my xib as well as the touchedButtonReturnToBeginning action is connected to my button. I've used my debugger to step through this method, so I have verified that it is getting called. All of the variables are appropriately set, but when I call scrollRectToVisible the scroll view just doesn't do anything.
Any ideas?
I don't know why that wouldn't work, but have you tried [self.containerScrollView setContentOffset:CGPointZero animated:YES]?
To make scrollRectToVisible works check your self.containerScrollView.contentSize. It should be big enough :)
Related
I'm having a serious problem that I just can't seem to fix and it's driving me insane for the last two days. I have searched far and wide and I can't find a solution, even though I have tried many.
I have a UITextView inside a UIScrollView. I am able to dynamically resize the UITextView inside the scrollview to display the text. But when the UITextView contains very large text it gets cut off when I scroll almost to the end. However, the UIScrollView's frame is still being sized correctly.
I read these posts: this this and many similar ones.
The UIScrollview and UITextview are both created in the xib using AutoLayout.
Here is my current code and a screenshot as you can see the blank spot in the screenshot should be filled with text. please help.
- (void)viewDidAppear:(BOOL)animated
{
CGRect frame = self.longDescField.frame;
frame.size.height = self.longDescField.contentSize.height;
self.longDescField.frame = frame;
self.scrollView.contentSize = CGSizeMake(self.view.frame.size.width, self.longDescField.contentSize.height + 200);
self.scrollView.scrollEnabled = YES;
[self.scrollView flashScrollIndicators];
}
This issue has existed since iOS 7 and is still present in iOS 12.
However, I wasn't able to keep the normal scrolling behaviour by setting scrollEnabled = NO before the resize, as #igz recommended. Instead I switched scrolling on and off after the resize
// Resize text view here
textView.scrollEnabled = NO;
textView.scrollEnabled = YES;
This forced the cut off text to render correctly.
Thanks everyone for your help. This is ultimately what ended up working for me in iOS7.
I had to disable auto layout for this particular xib.
Then did the following:
[textView setScrollEnabled:YES];
[textView setText:text];
[textView sizeToFit];
[textView setScrollEnabled:NO];
For me the solution was to put sizeToFit after customizing the textView
[self.yourTextView sizeToFit];
This should be the last thing you do when manipulating the textview, should not be before you populate the content text.
This issue can be fixed by setting the contiguous layout property to false.
textView.layoutManager.allowsNonContiguousLayout = false
Although the documentation says that the default value is false, it is actually set to true for a UITextView.
Definitely iOS7. I had this same problem applying to all UITextViews that were resized, both xib and code generated. I found the textContainer.size needed adjusting after UITextView frame was changed.
I created this category code to adjust the textContainer.size but it also seems to need adjusting after setting the text value as well, so I have to call adjustAfterFrameChange after any text changes if they are not followed by setting the frame size.
This code makes the assumption that UITextView is not doing anything with setFrame: itself so take out setFrame: and call adjustAfterFrameChange manually if you want to avoid that risk
Edit: changed
self.textContainer.size = self.frame.size; // fix for cut off text
to
self.textContainer.size = self.contentSize; // fix for cut off text
#interface UITextView(Extras)
- (void)adjustAfterFrameChange;
#end
#implementation UITextView(Extras)
- (void)adjustAfterFrameChange {
#if defined(__IPHONE_7_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_7_0
if ([self respondsToSelector:#selector(textContainer)])
self.textContainer.size = self.contentSize; // fix for cut off text
#endif
}
- (void)setFrame:(CGRect)frame {
[super setFrame:frame];
[self adjustAfterFrameChange];
}
#end
Try this
[self.textView setContentInset:UIEdgeInsetsMake(-8.0, 0, -8.0, 0)];
It work for the cut off text display in the UITextView.
I had a similar issue, wherein long text was getting cut off after a resize of the text view.
Turning off scrollingEnabled before the resize seemed to fix it. Sure seems like an IOS 7 bug.
We had the same problem, except the left half or right half of the UITextView was getting cut off. Happened on both iOS 7 and iOS 6, on a variety of phones. Calling:
myTextView.scrollEnabled = NO;
in viewWillAppear worked around the problem.
Just try this.
In IOS 8 and Xcode 6.3,
textview.scrollEnabled=YES;
[self.textview setContentInset:UIEdgeInsetsMake(-10.0, 0, -5.0, 0)];
We had an issue like this with the rollout of iOS7. When we called setText which added a new line (or lines) to our UITextView, the textview wasn't using the correct new height for its redrawing. The setNeedsDisplay, setNeedsLayout, redrawing layers, redrawing the entire view, etc all didn't work. Finally we forced a loss and gain of focus:
[textView resignFirstResponder];
[textView becomeFirstResponder];
This forced the height recalculation and correct redraw. Thankfully it does not cause the keyboard to pop out and in, but it's worth regression testing that on any iOS versions your app supports.
This happens all the way, from in Interface Builder too.
When text view selected, in Utilities Inspector uncheck the option Shows Vertical Indicator. The cropped text appears now.
None of these answers worked for me.
I was fooling with the storyboard and somehow it's working now. It still looks wrong in the storyboard but on the device it's now displaying fine.
I did various things, including toggling many of the options for the textfield.
I think what fixed it for me was making the view larger, building, and making it the right size again.
My apologies for a vague uncertain answer, but maybe it helps. This project was originally written for iOS 5, and the text view may not have been messed with much since then.
I have the same Problem for a textview (without a scrollview). Solved this (Xcode 7.3.1, iOS 9.3) just by unchecking "Scrolling Enabled" in the Attributes Inspector.
I may be wrong but I do not understand your problem thoroughly but what is the use of using a UIScrollView since with the UITextView class implements the behavior for a scrollable, multiline text region ?
You should discard the UIScrollView.
I am facing the same situation. I have to disable the UITextView's scrolling and doing that causes the last line is cliped. Here is my solution:
//In the UITextView subClass, override "gestureRecognizerShouldBegin" and let the scrolling of UITextView remain on.
-(BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]] && gestureRecognizer.view == self){
return NO;
}
return [super gestureRecognizerShouldBegin:gestureRecognizer];
}
In Swift I fixed this issue by simply setting the textContainerInset of my UITextView:
textView.textContainerInset = UIEdgeInsets(top: 0.0, left: 0.0,
bottom: 50.0, right: 0.0)
This worked for me:
textView.scrollEnabled = NO;
//resize here
textView.scrollEnabled=YES;
I'm trying to get my code to programmatically zoom into a small area of the larger picture. I'll add the tap code later, but right now I just want to see it work.
The zoomToRect in this code does absolutely nothing and I simply don't understand why. When I build it, the image just sits there at the 0,0 origin.
I've tried using:
setContentOffset and scrollRectToVisible and both these work fine -the image moves to the specified coordinates. But neither of these is what I want, because I need to move and zoom the image, not just move it.
But zoomToRect utterly refuses to do anything. I've read about 50 pages of examples and tutorials on this now and not a damn thing works. I'm tearing my hair out not knowing why. Clearly I'm missing some really fundamental or important point.
UIImage *myFirstImage = [UIImage imageNamed:#"manga_page.jpg"];
UIImageView *myFirstImageView = [[UIImageView alloc] initWithImage:myFirstImage];
[myFirstImageView setFrame:CGRectMake(0, 0, myFirstImage.size.width, myFirstImage.size.height)];
UIScrollView *myFirstScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[myFirstScrollView setContentSize:CGSizeMake(myFirstImage.size.width, myFirstImage.size.height)];
[myFirstScrollView addSubview:myFirstImageView];
[self.view addSubview:myFirstScrollView];
[myFirstScrollView zoomToRect:CGRectMake(300, 300, 300, 300) animated:YES];
The problem was that I hadn't defined the delegate for zooming - see viewForZoomingInScrollView (bottom of page) here:
https://developer.apple.com/library/ios/documentation/uikit/reference/uiscrollviewdelegate_protocol/Reference/UIScrollViewDelegate.html#//apple_ref/occ/intfm/UIScrollViewDelegate/viewForZoomingInScrollView
I don't have a code fragment in Objective C as I switched to the Xamarin framework. However the C# solution is as follows:
scrollView.ViewForZoomingInScrollView = delegate (UIScrollView sv) { return imageView; };
Where imageView is the UIImageView containing the image to be scrolled around.
Set the maximumZoomScale and minimumZoomScale properties for the UIScrollView.
I'm doing a cool CA3DTransform while a UIScrollview is scrolling in the scrollViewDidScroll delegate method. It works perfectly when you use your finger to scroll, so when scrolling manually everything is perfect.
But, when I set scrollview contentoffset programmatically like:
[scrollView setContentOffSet:CGPointMake(0,460) animated:YES];
It still calls the delegate method scrollviewdidscroll, so the same animation methods are called, so I still see the correct animation, BUT, somehow parts of the view are missing during and after the animation! I've tried to set the layer.zPosition on all things and it doesn't seem to help. It should be fine since manually scrolling does work without parts of views going missing... Somehow calling this method programmatically differs and I have no idea why!
Post your question in this way is not very clear, considering that with the delegate scrollViewDidScroll, I can print me the code, either manually or programmatically.
...
UIScrollView *sv = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 10, 320, 200)];
[sv setContentSize:CGSizeMake(640, 200)];
sv.delegate = self;
[sv setContentOffset:CGPointMake(320, 0) animated:YES];
[self.view addSubview:sv];
...
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
NSLog(#"---%#---", NSStringFromCGPoint(scrollView.contentOffset));
}
In this simple example, you can see that the delegate actually works.
Excuse the simplicity of the answer, but the only question you ask is hard to give you help.
I had a similar problem (in the context of using a scrollview for a slideshow) but solved it by using scrollRectToVisible:NO (NO for no animations), and wrapped that inside a UIView animation block where I also put my animation code.
Using this method to hide the status bar:
[[UIApplication sharedApplication] setStatusBarHidden:YES animated:YES];
When setting "hidden" back to NO, the tap-to-scroll-to-top (in UIWebView, UITableView, whatever) doesn't work any more, and requires a restart of the app to get the functionality back.
Is this a bug (I filed a rdar anyhow) or have I missed a step? Should I perhaps expect this behavior since the statusBar "loses touch" somehow with the respective view?
You could try setting the ScrollsToTop property to true again after re-showing it:
[currentView setScrollsToTop:YES];
If that's not working, are you definitely only showing one view? If there is more than one scrolling view a scrollViewDidScrollToTop message is ignored...
In iOS 5.0 you can access the scrollview property of the UIWebView
webView.scrollView.scrollsToTop = YES;
The following fix by Alex worked for me. Thanks!
((UIScrollView *)[[webView subviews] objectAtIndex:0]).scrollsToTop = NO;
Being in a hurry this fix worked great, however given more time I might've subclassed the UIWebView and accessed the protected UIScrollView member directly.
The worry I have with Alex' method is that it assumes that UIScrollView is at index zero of the subviews (encapsulation allows private members to change). Which suggests another solution still:
for (UIView* v in [webView subviews])
{
if ([v isKindOfClass:[UIScrollView class]])
{
(UIScrollView *)v.scrollsToTop = NO;
}
}
I was having a similar problem where the scroll-to-top functionality was lost. Turns out this will only work when you have only one active view at a time (within the same scroll view). In my case I had a table view and another view which would fade in/out. Adding a removeFromSuperview at the end of the animation did the trick.
The answer was in the UIScrollView.h file comments:
/*
this is for the scroll to top gesture. by default, a single scroll visible scroll view with this flag set will get the call. if there is more than one visible with this
flag set or the delegeat method returns NO, the view isn't scrolled
*/
#property(nonatomic) BOOL scrollsToTop; // default is YES. if set, special gesture will scroll to top of view after consulting delegate
You can use the following code to have the UIWebView ignore scrollToTop without the extra UIScrollView:
((UIScrollView *)[[webView valueForKey:#"_internal"] valueForKey:#"scroller"]).scrollsToTop = NO;
I had a similar problem after playing a Youtube video within my app. scrollsToTop was still set to YES but tapping the status bar had no effect.
I finally realised that my app window was no longer the key window. After adding the following line to a UIWindow subclass (which I already had for other reasons) everything worked as it should again:
if (![self isKeyWindow]) [self makeKeyWindow];
I just ran across a similar behavior in the app I'm currently working on. In its case, if you load a YouTube video from within a UIWebView, scroll to top stops working for the rest of the application's life cycle. I kind of assume this might happen after loading the movie player as well, but haven't confirmed. That functionality has been around a lot longer and probably has fewer bugs.
When there are multiple scrollview, you can also set scrollUpToTop to NO for the others scrollview. cf:
setScrollsToTop with multiple UIScrollView classes and/or subclasses(UITableView)
I want to add my case, I add an UIWebView on an UIScrollView, as h4xxr had answered on the top:
If there is more than one scrolling view a scrollViewDidScrollToTop message is ignored
So, I get a simply way to make it work on webView: just set the scrollView·s scrollsToTop property false.
And when tap the status bar, it won`t got intercepted by the scrollView, and the webView scrolls to the top!
UIScrollView *scrollView = [[UIScrollView alloc] init];
scrollView.frame = self.view.bounds;
scrollView.scrollsToTop = false; //igore scrollView`s scrollsToTop
[self.view addSubview:scrollView];
UIWebView *webView = [[UIWebView alloc] init];
webView.frame = scrollView.bounds;
[scrollView addSubview:webView];
Once again I've searched for about 45 minutes for an answer to this question and I thought I might have found the answer but then the situation I was reading wasn't exactly like the one I'm running into.
when I add my view it seems that it's not completely covering the window I was able to get rid of the status bar at the top but there is a section of space at the bottom that the view is not covering
alt text http://img177.imageshack.us/img177/8844/picture1zjv.png
as you can see from the screenshot there is an orange bar...it's orange because I know what it actually is under there (it's the viewController's view but everything I try I can't seem to get the added view to cover the screen.
this is the only code that's run
(void)viewDidLoad {
[super viewDidLoad];
[self.view addSubview:mainMenu];
}
Any help would be appreciated.
There are a few things that might be going wrong:
Your frame might be too short. In viewDidLoad: you can add a debug statement to check its height:
NSLog(#"Height is %f", self.view.frame.size.height);
It looks like you want that value to be 480, the full height of the screen.
Your origin might be too high. Similarly check your y offset:
NSLog(#"y origin is %f", self.view.frame.origin.y);
It looks like you want that value to be 0.
The origin of your superview might be too high. Assuming you this view only has one superview, this code will help check the absolute coordinates of your view's origin:
CGPoint absoluteOrigin = [self.view convertPoint:self.view.frame.origin
toView:self.view.superview];
NSLog(#"y origin in superview is %f", absoluteOrigin.y);
You can just tag on a few extra .superview's to find out the coordinates in terms of the prior views.
By the way, instead of just using 480 as a magic number in your code, you might want to do something like this to get the full height:
CGRect appFrame = [[UIScreen mainScreen] applicationFrame];
CGFloat screenHeight = appFrame.size.height;
The applicationFrame property takes into account whether or not the status bar is displayed.
You should post your code, but in general, you can make a UIView fill the screen as follows:
UIView *foo = [[UIView alloc] initWithFrame:CGRectMake(0,0,320,480)];
And you can set the frame later:
foo.frame = CGRectMake(0,0,320,480);
To fill the screen, you should use a 320 x 480 Rectangle, at origin (0,0). That's what that CGRectMake function above creates.
I've had this problem before, I fixed it by just moving the view down 20 pixels...
When you use interface builder it has that nifty little "simulate status bar" or "simulate toolbar" feature but I think its kind of finnicky.
Both Andrew and Tylers answers should work though, no shame in doing things programmatically :). If you are creating the stuff in interface builder, just do Andrew's second line though, don't need to reinitialize.
Ok, well I figured it out and now I feel kind of stupid...I went back to IB and realized that the height of each view was set at 460 and not 480...you guys did give me a bunch of good information and I appreciate it all. I wish I could mark them all as answers.
Thank you again,
BWC