I have around 13 UITableViews on UIScrollview,scrollview scrolls horizontally and shows all uitableviews.
on each scroll I want to scroll to particular point and i did that using the code
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
if(position >= 12)
position=-1;
position++;
[self scrollToPosition:position];
}
-(void)scrollToPosition:(int) tempPos{
[scrollView setContentOffset:CGPointMake(635*tempPos+tempPos*5, 0)];
}
Problem is: How can I detect whether I scrolled to left or right ??
as per my code whatever direction of the scroll it'll just increase contentOffset, But I want to achieve left scroll as well as right scroll along with setting particular contentOffset to each scroll.
Also, If i scroll any of my uitableViews vertically, then these delegates will get called and set the contentOffset so that it'll scorll horizontally...! so that I cant see the content of the table I scrolled.
I want to scroll horizontally to show each uitableViews(by setting some contentOffset) also I want to achieve verticle scrolling of each table individually.
and How to find which table is currently scrolling with multiple UITableViews on UIScrollView ??
any problem with my code ?? how to achieve this ??
Thanks,
Ranganatha
Related
I'd like to have a UITableView with cells wider than 320 points. The user should be able to scroll sideways to be able to view different parts of a UITableViewCell. Is this kind of behavior possible with a UITableView, or should I go and try to implement a tiling UIScrollView?
I tried wrapping a UITableView within a UIScrollView, and the results are terrible - they compete for the scroll gestures and most of the time the scroll view wins, preventing the table from being traversed vertically.
Any input is appreciated!
Thank you!
Update: I tried the proposed solution and it scrolls properly, but the tableview is still only 320 pixels wide. Is tableView's width linked to the window bounds ?
Wrapping the table view with the scroll view is the right way.
UIScrollView with
Show horizontal scrollers
scrolling enabled
autosize to full screen
Inside that, a UITableView
shows vertical scrollers
scrolling enabled
Then I set the table view's frame, with w, being the calculated width of the table view with all columns, whatever your width, and kTableScrollViewHeight being the fixed height of both the table view and the scroll view, in my case, for example 367 points (screen minus status, navbar and tabbar):
tv.frame = CGRectMake(0, 0, w, kTableScrollViewHeight);
and the scroll view's content size
scrollView.contentSize = CGSizeMake(w, kTableScrollViewHeight);
If you want the scroll-to-top behavior when the user taps the status bar, you might want to set
scrollView.scrollsToTop = NO;
because otherwise the scroll view will take away the tap from the table view.
I have a UIScrollView in which vertical only scrolling is enabled. I'm displaying a grid of buttons (similar to the photo viewer image grid). The grid has to be drawn differently based on screen orientation, so that all of the screen real estate is used. Given the size of my buttons, I can fit 3 per row in portrait, and 4 per row in landscape.
I reposition all of the buttons in: willRotateToInterfaceOrientation:duration and then call: setContentSize: on my UIScrollView. Everything seems to work just fine, with the exception of the auto-scrolling that occurs after the call to SetContentSize:. In other words, let's say I was in portrait, and scrolled 3/4 of the way down the list, when I rotate to landscape, it auto-scrolls all the back up to the top.
The interesting thing is, in the same scenario, if I were to do a small flick scroll up or down, and then immediately rotate the device, the scroll view redraws correctly, and retains the current scroll position!
So, to be clear, the culprit here seems to be SetContentSize:, but obviously I have to call that for the scroll view to scroll correctly.
Any ideas on how I can retain the current scroll position?
Thanks!
You might try implementing the UIScrollViewDelegate method scrollViewShouldScrollToTop:, which tells the caller whether to scroll to the top or not. You may have to have some flag in your delegate that indicates if a rotation is underway or not, because under normal conditions you may actually want the ability to tap the status bar and have the scroll view scroll to the top.
If, on the other hand, you don't ever want the scroll view to scroll to the top automaticlly, simply implement that delegate method and have it return NO.
I had this problem, just did this and it works well for me
- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
//calculate percentage down scrollview currently at
float c = self.scrollView.contentOffset.y / self.scrollView.contentSize.height;
//reposition subviews in the scrollview
[self positionThumbnails:toInterfaceOrientation];
//set the new scrollview offset to the same percentage,
// using the new scrollview height to calculate
self.scrollView.contentOffset =
CGPointMake(0, c * self.scrollView.contentSize.height);
}
In my case, I have a scrollview with a fixed width to device size, and variable height
I have a UIScrollView that has a single child view within it. If I set the contentSize of the UIScrollView immediately after creation, everything works as I expect and I get scrolling.
The challenge is the view within the UIScrollView is dynamically sized. The width is fixed, but the height is unknown at the time I set up the scrollview.
When I do a [scrollView setContentSize:CGRectMake(...)] after the inner view does it's thing, the scrollview updates to the proper size and scrolling works. So basic scrolling works fine.
However, the major problem is that when I setContentSize at a later point, the UIScrollView decides to scroll down(with animation) towards the end of the scrollview, which is not what I want, I want the scroll to stay at the top, and let the contents within the scrollview either get bigger or smaller, without changing the apparent scroll position.
What am I missing?
Why don't you also call [scrollview setContentOffset:CGPointMake(0,0)]; when you call the setContentSize?
To force UIScrollView to scroll only e.g. horizontally, I always set non-scrollable value for contentSize to 0, using:
CGSizeMake(contentSize.width, 0).
I have a UIScrollView which I create and size dynamically using...
scrollView.contentSize = CGSizeMake(scrollView.frame.size.width , length);
I then add subviews to the UIScrollView.
I do have scrollView.showsVerticalScrollIndicator = YES;
When scrolling the scroll indicator never appears.
Even if I call [scrollView flashScrollIndicators] nothing happens.
Ideas?
Had the same problem and couldn't find the cause. The last answer gave the final hint: whenever I added new subviews I first removed all existing subviews from the scrollview (and apparently also the scroll indicators).
After checking in my loop, if the subview really was of the kind I wanted to be removed the scroll indicators showed up:
for (NSObject * subview in [[[scrollView subviews] copy] autorelease]) {
if ([subview isKindOfClass:[MySubView class]]) {
[(MySubView*)subview removeFromSuperview];
}
}
Update: changed code to Nikolai's suggestion
When I've dealt with this before, in my implementation of a grid, I would occasionally get some cells over the top of the scroll indicator. To fix this I am now inserting subviews at index 0 rather than adding them, which adds them to the top. So try something like this:
[scrollview insertSubview:subview atIndex:0];
For me, the horizontal indicator had mysteriously disappeared in my app on iOS 7. Later found out that for some strange reason, I had to enable both Shows Horizontal Indicator and Shows Vertical Indicator to make the horizontal one show up. If I set it to not show the vertical indicator, it would also not show horizontal indicator.
I fix this by adding this code after add new subview:
self.showsVerticalScrollIndicator = NO;
self.showsVerticalScrollIndicator = YES;
It will also happen (at least in the case of a UITableView) if the contentSize is too small for the table view to scroll. If you have enabled bouncing, then the tableview does not actually scroll and does not display the indicators therefore. Try fitting more content inside.
It can happen also if the parent of the scrollview is smaller horizontally than the scroll view itself :
The scroll bar is stuck to the right side of the ScrollView / TableView and this right side is not visible due to the parent bounds ( with a clipToBounds hidding it for instance).
I've seen this issue so I share it in case it can help.
Just check the width of your ScrollView's frame not to be bigger than the width of its parent view frame.
Two conditions,
If you are using a storyboard
If you are using a UITableView inside a UIViewController
Then, you should check your indicator insets are set to 0 (or any other number that is relevant to your autolayout):
Noticed this when the UIScrollView was a 48 px tall horizontal band, scrollable horizontally. Maybe Cocoa decides the area is too small for a scroll indicator...
Let's say, i have two tableview inside a scrollview. After i scrolled up & down tableview1, and then touch and swipe to scroll the scrollview horizontally to tableview2, i want tableview2 to have the same vertical (up & down) position as tableview1. is there any way to achieve that?
thanks
You can put code in the UITableViews' viewWillDisplay: methods that grabs the other table view's scroll position (called a "content offset" in scroll view parlance) and calls setContentOffset:animated:. This way, whenever either scroll view will appear on the screen, it will automatically scroll to the other view's position.