Here's how the scroll views work: One scroll view is paging enabled in the horizontal direction. Each 'page' of this scroll view contains a vertically scrolling UITableView. Without modification, this works OK, but not perfectly.
The behaviour that's not right: When the user scrolls up and down on the table view, but then wants to flick over to the next page quickly, the horizontal flick/swipe will not work initially - it will not work until the table view is stationary (even if the swipe is very clearly horizontal).
How it should work: If the swipe is clearly horizontal, I'd like the page to change even if the table view is still scrolling/bouncing, as this is what the user will expect too.
How can I change this behaviour - what's the easiest or best way?
NOTE For various reasons, a UIPageViewController as stated in some answers will not work. How can I do this with cross directional UIScrollViews (/one is a table view, but you get the idea)? I've been banging my head against a wall for hours - if you think you can do this then I'll more than happily award a bounty.
According to my understanding of the question, it is only while the tableView is scrolling we want to change the default behaviour. All the other behaviour will be the same.
SubClass UITableView. UITableViews are subClass of UIScrollViews. On the UITableView subClass implement one UIScrollView's UIGestureRecognizer's delegate method
- (BOOL)gestureRecognizer:(UIPanGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UISwipeGestureRecognizer *)otherGestureRecognizer
{
//Edit 1
//return self.isDecelerating;
//return self.isDecelerating | self.bounces; //If we want to simultaneous gesture on bounce and scrolling
//Edit 2
return self.isDecelerating || self.contentOffset.y < 0 || self.contentOffset.y > MAX(0, self.contentSize.height - self.bounds.size.height); // #Jordan edited - we don't need to always enable simultaneous gesture for bounce enabled tableViews
}
As we only want to change the default gesture behaviour while the tableView is decelerating.
Now change all 'UITableView's class to your newly created tableViewSubClass and run the project, swipe should work while tableView is scrolling. :]
But the swipe looks a little too sensitive while tableView is scrolling. Let's make the swipe a little restrictive.
SubClass UIScrollView. On the UIScrollView subclass implement another UIGestureRecognizer's delegate method gestureRecognizerShouldBegin:
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
CGPoint velocity = [(UIPanGestureRecognizer *)gestureRecognizer velocityInView:self];
if (abs(velocity.y) * 2 < abs(velocity.x)) {
return YES;
}
}
return NO;
}
We want to make the "swipe is clearly horizontal". Above code only permits gesture begin if the gesture velocity on x axis is double than on y axis. [Feel free to increase the hard coded value "2" if your like. The higher the value the swipe needs to be more horizontal.]
Now change the `UiScrollView' class (which has multiple TableViews) to your ScrollViewSubClass. Run the project. :]
I've made a project on gitHub https://github.com/rishi420/SwipeWhileScroll
Although apple doesn't like this method too much:
Important: You should not embed UIWebView or UITableView objects in UIScrollView objects. If you do so, unexpected behavior can result
because touch events for the two objects can be mixed up and wrongly
handled.
I've found a great way to accomplish this.
This is a complete solution for the problem. In order to scroll the UIScrollView while your UITableView is scrolling you'll need to disable the interaction you have it.
- (void)viewDidLoad
{
[super viewDidLoad];
_myScrollView.contentSize = CGSizeMake(2000, 0);
data = [[NSMutableArray alloc]init];
for(int i=0;i<30;i++)
{
[data addObject:[NSString stringWithFormat:#"%d",i]];
}
UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
[self.view addGestureRecognizer:tap];
}
- (void)handleTap:(UITapGestureRecognizer *)recognizer
{
[_myTableView setContentOffset:_myTableView.contentOffset animated:NO];
}
- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = NO;
}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = YES;
}
To sum up the code above, if the UITableView is scrolling, set userInteractionEnabled to NO so the UIScrollView will detect the swipe. If the UITableView is scrolling and the user taps on the screen, userInteractionEnabled will be set to YES.
Instead of using UIScrollView as a container for these multiple table views, try using a UIPageViewController.
You can even integrate this into your existing view controller setup as a child view controller (directly replacing the UIScrollView).
In addition, you'll likely want to implement the required methods from UIPageViewControllerDataSource and possibly one or more of the methods from UIPageViewControllerDelegate.
Did you try the methods : directionalLockEnabled of both your table and scroll and set them up to horizontal for one and vertical for the other ?
Edit :
1)
What you want to do is very complicate since the touch wait some time (like 0.1s) to know what your movement will be. And if your table is moving, it will take your touch immediately whatever it is (because it's suppose to be reactive movement on it).
I don't see any other solution for you but to override touch movement from scratch to detect immediately the kind of mouvement you want (like if the movement will be horizontal) but it will be more than hard to do it good.
2)
Another solution I can advise you is to make your table have left and right margin, where you can touch the parent scroll (pages thing so) and then even if your table is scrolling, if you touch here, only your paging scroll will be touched. It's simpler, but could not fit with your design maybe...
Use UIPageViewController and in the -viewDidLoad method (or any other method what best suits your needs or design) get UIPageViewController's UIScrollView subview and assign a delegate to it. Keep in mind that, its delegate property won't be nil. So optionally, you can assign it to another reference, and then assign your object, which conforms to UIScrollViewDelegate, to it. For example:
id<UIScrollViewDelegate> originalPageScrollViewDelegate = ((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]).delegate;
[((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]) setDelegate:self];
So that you can implement UIScrollViewDelegate methods with ease. And your UIPageViewController will call your delegate's -scrollViewDidScroll: method.
By the way, you may be obliged to keep original delegate, and respond to delegate methods with that object. You can see an example implementation in ViewPagerController class on my UI control project here
I faced the same thing recently. My UIScrollview was on paging mode and every page contained a UITableView and like you described it worked but not as you'd expected it to work. This is how solved it.
First I disabled the scrolling of the UIScrollview
Then I added a UISwipeGestureRecognizer to the actual UITableView for left and right swipes.
The action for those swipes were:
[scroll setContentOffset:CGPointMake(currentPointX + 320, PointY) animated:YES];
//Or
[scroll setContentOffset:CGPointMake(currentPointX - 320 , PointY) animated:YES];
This works flawlessly, the only down side is that if the user drags his finger on the UITableVIew that will be considered as a swipe. He won't be able to see half of screen A and half of screen B on the same screen.
You could subclass your scroll view and your table views, and add this gesture recognizer delegate method to each of them...
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:
(UIGestureRecognizer *)otherGestureRecognizer {
return YES;
}
I can't be sure this is exactly what you are after, but it may come close.
I have two UITableView. I need to scrolling toghether vertically.
I tried to insert both tables inside a UIScrollView and disabling scrolling of UITableView.
It works but the UITableView which is below is cut it seems as if the table size was set to the maximum size of the screen).
The UITableView i put them inside the view through the storyboard.
I tried to increase the frame of the table within the viewDidLoad method but does not work. If I insert it inside the method viewDidAppear works but it makes me a failure when I click on a UICell and then came back.
Any suggest?
you should work with sections. But if this is not an option for what ever reason you could listen to the scrollViewDidScroll: delegate method and set the offset of the two tables as appropriate. Small Example:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
if (scrollView == self.firstTable) {
self.secondTable.contentOffset = scrollView.contentOffset;
} else {
self.firstTable.contentOffset = scrollView.contentOffset
}
}
you might need to store the touched table in an ivar to determine which scrollevents are initialized by user-interaction and which by your code to avoid 'scroll'-loops.
EDIT:
I might misunderstood your question. You want them to behave as one Table?
I have a table with static cells. One of these cells has a view in it with a pan gesture recogniser on it.
When I am scrolling down my tableview, when I get to the cell with the view with pan gesture recogniser, scrolling doesn't seem to work. If I touch outside the view (to the side or top or bottom) it works and I can scroll. I have an if statement in my gesturerecognizer that tests whether a certain area has been touched, and if so performs an action.
I have looked at this issue (http://stackoverflow.com/questions/3295239/uigesturerecognizer-blocking-table-view-scrolling) but setting cancelsTouchesInView to NO didn't work, I don't have anywhere setting the state property and using the method - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
I don't know where to get the 'otherGestureRecognizer' from or what object to call that method on.
I'm assuming I wan't to put my gesture recogniser as the first argument, and the tableview's scroll gesture recogniser as the otherGestureRecogniser, is that correct? If so, how do I get that?
UIPanGestureRecognizer *windPanGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(moveWindHandle:)];
[self.windRangeView addGestureRecognizer:windPanGesture];
Then in my moveWindHandle:
-(void)moveWindHandle:(UIPanGestureRecognizer *)gesture
{
gesture.cancelsTouchesInView = NO;
isMovingHandle = [self isPoint:startedTouchAt insideHandle:_toHandleWindImageView];
if(isMovingHandle) {
if(gesture.state == UIGestureRecognizerStateBegan) {
//do stuff
}
}
else
{
//i want it to ignore this gesture and just scroll like normal if that is what hte user did
}
}
I have set the tableviewcontroller as a UIGestureRecognizerDelegate, but I don't know what to do with that.
You would not be the one calling -gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:. That method is called by the system. You need to set your table view controller as the delegate for your window pan gesture.
windPanGesture.delegate = self;
At that point, when you do the pan, the system will call the delegate method -gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer: with your gesture recognizer as one argument and the scroll view's gesture recognizer as the other.
Update
You may also want to implement the -gestureRecognizerShouldBegin: method and return NO if you are not in one of the certain areas.
Is there a proper way to determine if a NSView is actually drawn in the current view hierarchy or not, considering cases like:
The view is completely offscreen (not mandatory)
The view is not on top of the view hierarchy
The -isHidden and -isHiddenOrHasHiddenAncestor are unfortunately not set when e.g. a view disappears because a tab view switches to another tab.
The reason for this is that I have an attached child window and I would like to be able to hide it as well when the view that it is attached to is not drawn.
I have found a trick to tell if it is visible, but it requires subclassing. It works by toggling an ivar on 2 events.
- (void)discardCursorRects {
isDrawn_ = NO;
[super discardCursorRects];
}
- (void)resetCursorRects {
isDrawn_ = YES;
[super resetCursorRects];
}
Whether (or when) it's drawn is supposed to be "none of your business" and really have nothing to do with whether or not it's on-screen. Use NSView's -viewDidMoveToSuperview or -viewDidMoveToWindow to manage this.
i made a second uiview in mei .xib file. the first view is landscape and i get it by following code
ItemController *newItem;
newItem = [[ItemController alloc] init];
newItem.view.....
how can i "activate" the second view, so i can use it with
newItem.view2...
is that possible? the second view is portait mode, so it should be hidden and when turning the ipad the first view should be hidden and the second gets visible.
thanks
If I understand your question correctly, you can use the method willRotateToInterfaceOrientation:duration: in UIViewController.
You can declare two UIView variables and set connections to them using IB:
IBOutlet UIView *view1;
IBOutlet UIView *view2;
Then, in willRotateToInterfaceOrientation:duration: you can swap the views. Assuming that your ItemController is a subclass of UIViewController, you could have something like this:
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
if (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft) || (toInterfaceOrientation == UIInterfaceOrientationLandscapeRight) {
[self setView:view1];
}
else {
[self setView:view2];
}
}
When the user rotates the iPad this method will get called automatically.
NOTE: make sure you set shouldAutorotateToInterfaceOrientation: to return YES, and you may have to check the orientation to set the view property to the correct view initially.
EDIT: My answer is assuming that you have two views with distinct layouts/elements and not two views that are essentially the same thing sized for different orientations. If the latter is the case, there is probably a better way to do it using only one view.
The approach you are taking will lead you to a trouble situation when you have some IBActions to associate with click of buttons or change the label text (which is on xib) etc.
The best approach is to change the frame height width and positions when the orientation changes. Although this is difficult in beginning but it will save you from lots of troubles.
For assistance check Rotate UIViewController to counteract changes in UIInterfaceOrientation
Hope this helps.
Thanks,
Madhup