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Stop UIWebView from "bouncing" vertically?

Does anyone know how to stop a UIWebView from bouncing vertically? I mean when a user touches their iphone screen, drags their finger downwards, and the webview shows a blank spot above the web page I had loaded?

I've looked at the following possible solutions, but none of them worked for me:

http://www.iphonedevsdk.com/forum/iphone-sdk-development/996-turn-off-scrolling-bounces-uiwebview.html

http://forums.macrumors.com/showthread.php?t=619534

How do I stop a UIScrollView from bouncing horizontally?

I hope you have considered the usability implications of disabling that feature. It's there for a reason. That said, I'm curious, too, how you'd do that.
The way I have it embedded in my app, it appears seemlessly with some other view elements I have, and the only time it doesn't appear so is when the bounce happens.... Definitely a good point though!

S
S.M.Mousavi
for (id subview in webView.subviews)
  if ([[subview class] isSubclassOfClass: [UIScrollView class]])
    ((UIScrollView *)subview).bounces = NO;

...seems to work fine.

It'll be accepted to App Store as well.

Update: in iOS 5.x+ there's an easier way - UIWebView has scrollView property, so your code can look like this:

webView.scrollView.bounces = NO;

Same goes for WKWebView.


It works. No subclassing required and if Apple ever change the UIWebView hierarchy, it shouldn't crash.
This fix seems to only work in my OS 4.1 Simulator, not on my OS 3.1.3 iPhone. Does anybody know if this fix only works on particular OS versions?
@MirukRusin - How can you guarantee that this app will be accepted based on three lines of code? :P
@Mirek - You missed my point. How do you know that nothing else in the app will get it rejected?
This worked fine for me. For convenience, I added a category to UIWebView so I could call [webView setBounces:NO] anywhere I wanted to.
B
Brad Parks

I was looking at a project that makes it easy to create web apps as full fledged installable applications on the iPhone called QuickConnect, and found a solution that works, if you don't want your screen to be scrollable at all, which in my case I didn't.

In the above mentioned project/blog post, they mention a javascript function you can add to turn off the bouncing, which essentially boils down to this:

    document.ontouchmove = function(event){
        event.preventDefault();
    }

If you want to see more about how they implement it, simply download QuickConnect and check it out.... But basically all it does is call that javascript on page load... I tried just putting it in the head of my document, and it seems to work fine.


This answer is the correct way to stop the vertical scrolling of the content within a UIWebView.
You could have given the whole answer, firstly I don't want to download a whole scource code of another app, and I can't even find it. Your answer relies on another website being the same as when you answered.
This answer & the accepted answer above seem to be required at times. In my case, I found that if the web view was not loaded yet, the bounciness would be there until the JS above was actually loaded into the system. So the answer seems to be that this and the accepted answer above are both, at times, required.
as Jessedc said, this will stop vertical scrolling, not only bouncing. that means if you have div or so that requires scrolling, it will not scroll.
Z
Zigglzworth

Well all I did to accomplish this is :

UIView *firstView = [webView.subviews firstObject];

if ([firstView isKindOfClass:[UIScrollView class]]) {

    UIScrollView *scroll = (UIScrollView*)firstView;
   [scroll setScrollEnabled:NO];  //to stop scrolling completely
   [scroll setBounces:NO]; //to stop bouncing 

}

Works fine for me... Also, the ticked answer for this question is one that Apple will reject if you use it in your iphone app.


This is the best and most simplest way. This should be the accepted answer! +1
Dont do that - my app got rejected for using the first line. Wasted so much time for me. i used [[webView.subviews lastObject] setScrollEnabled:NO]; and apple said it was a private API and hence rejected it; am about to resubmit now but used "userInteractionEnabled:NO" since i dont need any active links in the app.
UIWebView inherits from UIView. UIView has property subviews. What is private here? All of this you can find on developer.apple.com
I have something like 4 apps on the appstore using this. You app was clearly rejected for another reason. this is not a private API.
This is really not a good idea. You're relying on the fact that the UIScrollView is the first subview of UIWebView which may well be the case for now but this could easily change in future (even minor) updates to iOS or particular configurations. You should really do a for iteration over subviews to actually find the UIScrollView (it really isn't that much work and at least you are guaranteed to get a UIScrollView and not crash your program...
C
Community

In the iOS 5 SDK you can access the scroll view associated with a web view directly rather than iterating through its subviews.

So to disable 'bouncing' in the scroll view you can use:

myWebView.scrollView.bounces = NO;

See the UIWebView Class Reference.

(However if you need to support versions of the SDK before 5.0, you should follow Mirek Rusin's advice.)


E
Ego Slayer

Swift 3

webView.scrollView.bounces = false

R
Raf

Warning. I used setAllowsRubberBanding: in my app, and Apple rejected it, stating that non-public API functions are not allowed (cite: 3.3.1)


J
Jugal K Balara

In Swift to disable bounces

webViewObj.scrollView.bounces = false

G
Gavin Maclean

Brad's method worked for me. If you use it you might want to make it a little safer.

id scrollView = [yourWebView.subviews objectAtIndex:0];
if( [scrollView respondsToSelector:@selector(setAllowsRubberBanding:)] )
{
    [scrollView performSelector:@selector(setAllowsRubberBanding:) withObject:NO];
}

If apple changes something then the bounce will come back - but at least your app won't crash.


i
il Malvagio Dottor Prosciutto

On iOS5 only if you plan to let the users zoom the webview contents (e.i.: double tap) the bounce setting isn't enough. You need to set also alwaysBounceHorizontal and alwaysBounceVertical properties to NO, else when they zoom-out (another double tap...) to default it will bounce again.


p
pedro

I traversed the collection of UIWebView's subviews and set their backgrounds to [UIColor blackColor], the same color as the webpage background. The view will still bounce but it will not show that ugly dark grey background.


Actually it's a pretty bad one, because if Apple ever changes the internals of UIWebView, this hack could break.
s
spymaster

It looks to me like the UIWebView has a UIScrollView. You can use documented APIs for this, but bouncing is set for both directions, not individually. This is in the API docs. UIScrollView has a bounce property, so something like this works (don't know if there's more than one scrollview):

NSArray *subviews = myWebView.subviews;
NSObject *obj = nil;
int i = 0;
for (; i < subviews.count ; i++)
{
    obj = [subviews objectAtIndex:i];

    if([[obj class] isSubclassOfClass:[UIScrollView class]] == YES)
    {
        ((UIScrollView*)obj).bounces = NO;
    }
}

R
Rolf Hendriks

I was annoyed to find out that UIWebView is not a scroll view, so I made a custom subclass to get at the web view's scroll view. This suclass contains a scroll view so you can customize the behavior of your web view. The punchlines of this class are:

@class CustomWebView : UIWebview
...

- (id) initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
// WebViews are subclass of NSObject and not UIScrollView and therefore don't allow customization.
// However, a UIWebView is a UIScrollViewDelegate, so it must CONTAIN a ScrollView somewhere.
// To use a web view like a scroll view, let's traverse the view hierarchy to find the scroll view inside the web view.
for (UIView* v in self.subviews){
    if ([v isKindOfClass:[UIScrollView class]]){
        _scrollView = (UIScrollView*)v; 
        break;
    }
}
return self;

}

Then, when you create a custom web view, you can disable bouncing with:

customWebView.scrollView.bounces = NO; //(or customWebView.scrollView.alwaysBounceVertically = NO)

This is a great general purpose way to make a web view with customizable scrolling behavior. There are just a few things to watch out for:

as with any view, you'll also need to override -(id)initWithCoder: if you use it in Interface Builder

when you initially create a web view, its content size is always the same as the size of the view's frame. After you scroll the web, the content size represents the size of the actual web contents inside the view. To get around this, I did something hacky - calling -setContentOffset:CGPointMake(0,1)animated:YES to force an unnoticeable change that will set the proper content size of the web view.


L
Luke

Came across this searching for an answer and I eventually just lucked on an answer of my own by messing about. I did

[[webview scrollView] setBounces:NO];

and it worked.


J
Jason G

This worked for me, and beautifully too (I am using phonegap with webView)

[[webView.webView scrollView] setScrollEnabled:NO];

or

[[webView scrollView] setScrollEnabled:NO];

P
PP-RD

I tried a slightly different approach to prevent UIWebView objects from scrolling and bouncing: adding a gesture recognizer to override other gestures.

It seems, UIWebView or its scroller subview uses its own pan gesture recognizer to detect user scrolling. But according to Apple's documentation there is a legitimate way of overriding one gesture recognizer with another. UIGestureRecognizerDelegate protocol has a method gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer: - which allows to control the behavior of any colliding gesture recognizers.

So, what I did was

in the view controller's viewDidLoad method:

// Install a pan gesture recognizer                                                                                        // We ignore all the touches except the first and try to prevent other pan gestures                                                     
// by registering this object as the recognizer's delegate                                                                                        
UIPanGestureRecognizer *recognizer;                                                                                                               
recognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanFrom:)];                                                   
recognizer.delegate = self;                                                                                                                       
recognizer.maximumNumberOfTouches = 1;                                                                                                            
[self.view addGestureRecognizer:recognizer];                                                                                                          
self.panGestureFixer = recognizer;                                                                                                                  
[recognizer release]; 

then, the gesture override method:

// Control gestures precedence                                                                                                                            
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer                                                                                        
        shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer                                                  
{                                                                                                                                                         
        // Prevent all panning gestures (which do nothing but scroll webViews, something we want to disable in                                          
        // the most painless way)                                                                                                                         
        if ([otherGestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]])                                                                        
        {
            // Just disable every other pan gesture recognizer right away                                                                             
            otherGestureRecognizer.enabled = FALSE;
        }                                                                                                                                                  
        return NO;                                                                                                                                        
}              

Of course, this delegate method can me more complex in a real application - we may disable other recognizers selectively, analyzing otherGestureRecognizer.view and making decision based on what view it is.

And, finally, for the sake of completeness, the method we registered as a pan handler:

- (void)handlePanFrom:(UIPanGestureRecognizer *)recognizer 
{ 
    // do nothing as of yet
}

it can be empty if all we want is to cancel web views' scrolling and bouncing, or it can contain our own code to implement the kind of pan motions and animations we really want...

So far I'm just experimenting with all this stuff, and it seems to be working more or less as I want it. I haven't tried to submit any apps to iStore yet, though. But I believe I haven't used anything undocumented so far... If anyone finds it otherwise, please inform me.


N
NANNAV

Here's two newer potential solutions. Apparently, you can use jqtouch or pastrykit to disable scrolling. However, I haven't got these to work. You might be more competent.

turning off vertical scrolling

digging into pastrykit


N
NANNAV

fixed positioning on mobile safari

This link helped me lot.....Its easy.. There is a demo..


M
Matthew Ferguson

(Xcode 5 iOS 7 SDK example) Here is a Universal App example using the scrollview setBounces function. It is an open source project / example located here: Link to SimpleWebView (Project Zip and Source Code Example)


r
rpetrich

One of the subviews of UIWebView should be a UIScrollView. Set its scrollEnabled property to NO and the web view will have scrolling disabled entirely.

Note: this is technically using a private API and thus your app could be rejected or crash in future OS releases. Use @try and respondsToSelector


I tried this out, and it faults when I try it... Strangely, i can access and set scrollView.bounces (with no effect), but when I try and set scrollEnabled, it faults...
I believe the subview is called UIScroller, not UIScrollView. UIScroller is an undocumented and unsupported class that shares a lot in common with UIScrollView, but you can't depend on everything working the same way and not changing in future OS versions.
I did this on an iPad (not iPhone) app running iOS 3.2, and was able to get a UIScrollView out of my UIWebView. I successfully customized this view to change more than just its bouncing behavior so I can testify to this working on iPad. My app did not go through the app store, but I don't think there will be a problem with undocumented API's here. The clever part for this solution is that you're just traversing a UIView hierarchy and using a UIScrollView - both of which are perfectly kosher.
A
Alex

Look into the bounces property of UIScrollView. Quoth the Apple docs:

If the value of the property is YES (the default), the scroll view bounces when it encounters a boundary of the content. Bouncing visually indicates that scrolling has reached an edge of the content. If the value is NO, scrolling stops immediately at the content boundary without bouncing.

Make sure you're using the right UIScrollView. I'm not sure what the hierarchy looks like for a UIWebView, but the scroll view could be a parent, not a child, of the UIWebView.


u
user7116

To disable UIWebView scrolling you could use the following line of code:

[ObjWebview setUserInteractionEnabled:FALSE];

In this example, ObjWebview is of type UIWebView.


K
Kumaresan P

webView.scrollView.scrollEnabled=NO; webView.scrollView.bounces=NO;


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