I currently have a view controller that is comprised of a Navigation bar, followed by a UIView that has two UIButtons added as subViews. There is then a UITableView underneath that begins at the bottom of the container UIView.
At the moment, when the user scrolls the UITableView it goes behind the UIView and UIButtons. What I actually want to happen is for the UIView and UIButtons to move up with the table view but only by the value of their height which in this case is 58 pixels. The flow would be like this...
1) Table scrolls and the UIView moves with it for the first 58 pixels.
2) The user continues to scroll the table but the UIView "pins" itself just out of view under the navigation bar.
3) When the user scrolls the table back down the UIView is then picked up and dragged back into view. I believe the new Facebook app does something similar in the timeline.
I don't want to set the UIView as the TableHeaderView of the table as I also have a pull-to-refresh which then sits above the buttons and looks terrible. I've tried playing around with the contentOffset properties of the underlying scrollview of the table but have hit a brick wall.
Any advice on where to start would be appreciated.
Thanks
EDIT: I am gotten a little further and using this code to move the frame of the UIView.
-(void) scrollViewDidScroll:(UIScrollView *)scrollView
{
NSLog (#"Content Offset: %f", self.tableView.contentOffset.y);
NSLog (#"Button Frame: %f", self.btnBackground.frame.origin.y);
if (self.tableView.contentOffset.y > 0)
{
CGRect newFrame = self.btnBackground.frame;
newFrame.origin.x = 0;
newFrame.origin.y = -self.tableView.contentOffset.y;
[self.btnBackground setFrame: newFrame];
}
}
The problem now is that the scrollViewDidScroll delegate method doesn't get fired quickly enough if the table view is scrolled fast. The result is that the UIView doesn't quite make all way back to its original position when scroll quickly.
The scroll content offset is a good idea. Also if you tableview has only one section one approach is to do a custom header view representing the top level widgets. If there is more than one sections create an additional empty section which would return your custom header.
You can refer to this stack overflow post.
Customize UITableview Header Section
Well Asked Question (y)
well , for me i would first : use a main UIScrollView that contains both your topView and the tableView under it and that has the same width as your top UIView and UITableView and set its height to be height(tableView) + height(topView).
Second : since UITableView is a subClass of UISCrollView you can use scrollViewDidScroll delegate to know if the tableview is scrolled up or down.
in this cas you will have Two cases :
1) tableview is scrolled up = > you set the content offset of the main scrollView to be
[scrollView setContentOffset:CGPointMake(0, 58) animated:YES];
2) when the table view is scrolled down you can reset the content offset again
[scrollView setContentOffset:CGPointMake(0, 0) animated:YES];
Related
I have already built out 2 collection views, 1 horizontally scrolling (at the top) & 1 vertically scrolling (at the middle - bottom) that are used to view 2 different sets of content in my Objective-C iOS application similar to this Instagram screenshot:
I am trying to add functionality to make it so that the horizontally scrolling Collection View disappears when the user scrolls up on the vertically scrolling one. What is the best way to accomplish this task? I have looked up tutorials on adding a collection view in another collection view's cell but I cant find anything on just adding a collection view to the 1st cell of another collection view. What would be the best way to accomplish this functionality?
I think you should you use UITableView with UICollectionView. On the screeshot, I think horizontal collectionview is embedded in first cell of the tableview. And when use starts to scroll tableview, first row is gone as you want.
Edit
Create uitableview with 2 prototype cells. Create horizontall collectionview and embed it in first cell of tableview, this is first prototype cell. Then create second prototype cell for images. And when user will start scroll the tableview first cell will gone, as you want.
If you don't want to go with the other suggested method of embedding the horizontal collection view into the top cell of the vertical collection view, you could use the vertical collection view's scrolling callbacks (scrollViewDidScroll, since UICollectionView subclasses UIScrollView). When the vertical collection view scrolls, you can apply a transform to the top collection view to move it off the top of the screen based on the contentOffset of the vertical collection view, and then have it reappear once the contentOffset approaches 0.
Keep in mind that with this approach, the vertical collection view's frame will likely be the height of the screen minus the height of the horizontal collection view. Therefore, you will need a bit of extra logic to expand the vertical collection view's frame to take up the whole screen once the horizontal collection view has disappeared from sight. Otherwise, you will have an awkward blank bar at the top of the screen where the horizontal collection view initially was while you scroll.
You have two scroll view lets call it "cvHorizontal" and "cvVertical".
You can manage scrollViewDidScroll method to hide cvHorizontal when scrolled up and show cvHorizontal when scrolled down.
- (void)scrollViewDidScroll:(UIScrollView *)scrollView{
if (lastContentOffset > scrollView.contentOffset.y){
[self showCategory:YES];
lastContentOffset = scrollView.contentOffset.y;
} else if (lastContentOffset < scrollView.contentOffset.y) {
[self showCategory:NO];
lastContentOffset = scrollView.contentOffset.y;
}
}
-(void)showCategory:(BOOL)flag{
if(flag){
[UIView animateWithDuration:0.6 animations:^{
if(cvHorizontal.hidden ){
cvHorizontal.hidden=NO;
cvHorizontalHeight.constant=65.0f;//manage the cvHorizontal height and all the other constraints calculation if any
}
}];
}else {
[UIView animateWithDuration:0.6 animations:^{
cvHorizontal.hidden=YES;
cvHorizontalHeight.constant=0;
}];
}
}
I have a UITableViewController and I put a UIView right under the navigation item and above the actual table. The problem that I have is that the view scrolls with the tableview.
How would I get it to behave exactly like the nav bar, and have the items in the tableview scroll behind it.
Rather than having the view scroll, it should remain in its position and have everything go behind it. Sorry for reiterating, but I've found thats necessary sometimes.
The view you're placing above the cell in the storyboard becomes the table view's tableHeaderView.
You can make the header view appear fixed by resetting its frame.origin to the table view's bounds.origin every time the table view lays out its subviews:
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
UIView *header = self.tableView.tableHeaderView;
CGRect frame = header.frame;
frame.origin = self.tableView.bounds.origin;
header.frame = frame;
}
Result:
Assuming you don't want the map view to move then you could set its user interaction to false.
Alternatively you could set the header of your tableView (if you only have one section) to the map view.
I have an iPad app (XCode 4.6.3, iOS 6.2, ARC and Storyboards) which has the following structure on the bottom half of one of the scenes (all of the grids are UIViews, as is SubViewData).
The purpose is to have something that looks like a spreadsheet; I need to be able to scroll horizontally and the Left Grid will stay locked and if I scroll vertically, the Top Grid will stay locked.
This what it looks like now, without the scrolling (there is more to the right and also down):
UPDATE: This is the code that defines the UIViews:
I have looked in SO and Google and found no examples of this. Can someone please tell me what I need to change to get this code to work properly, or give me some good docs where I can get detailed information on contentOffset? (I have already read the UIScrollView, and it's no help!)
SOLVED - it's now working... this is how I got it to work, with the help of Fogmeister:
created a separate top row and left row UIView to hold the grid hours and staff names
embedded those new UIViews in UIScrollViews (Editor -> Embedd in scroll view)
followed the instructions from Fogmeister with regard to the code to make it happen.
This is the new structure:
And this is the code to make it happen:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGPoint mainOffset = [scrollView contentOffset];
NSLog(#"\n\nmainOffset.x: %f\nmainOffset.y: %f", mainOffset.x, mainOffset.y);
// set the horizontal offset of the main view onto the column headers
[self.topGridSV setContentOffset:CGPointMake(mainOffset.x, 0)];
if(mainOffset.x < 0) {
[self.topGridSV setContentOffset:CGPointMake(0, 0)];
[self.schedScrollView setContentOffset:CGPointMake(0, 0)];
}
// set the vertical offset onto the row headers
[self.leftGridSV setContentOffset:CGPointMake(0, mainOffset.y)];
if(mainOffset.y < 0) {
[self.leftGridSV setContentOffset:CGPointMake(0, 0)];
[self.schedScrollView setContentOffset:CGPointMake(0, 0)];
}
OK, the way I'd do this is to move the "header" row and column into their own scroll view.
So you'll have a scrollview in the middle with the actual cells in.
Then you'll have a scroll view along the top that ONLY CONTAINS the column headers.
Then have a scroll view down the left that ONLY CONTAINS the row headers.
Now, make the "owning" view controller the delegate of the "main" scrollView with the cells in.
So you'll have...
UIScrollView *cellScrollView;
UIScrollView *columnHeaderScrollView; // along the top
UIScrollView *rowHeaderScrollView; // down the left
You will have to set the content accordingly. Obviously, you don't want the headers in the cellScrollView. etc...
Now, in the delegate method...
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
// scrollView here should always be == self.cellScrollView
// as this is where the delegate method is triggered from.
CGPoint *mainOffset = [scrollView contentOffset];
// set the horizontal offset of the main view onto the column headers
[self.columnHeaderScrollView setContentOffset:CGPointMake(mainOffset.x, 0)];
// set the vertical offset onto the row headers
[self.rowHeaderScrollView setContentOffset:CGPointMake(0, mainOffset.y)];
}
Something like this should easily get the effect you're after.
With one scroll view
You will have three sub views of the scroll view and references to these...
cellView
leftView
topView
These are all subclasses of UIView.
Initially you will have a layout of something like...
leftView frame == [0, 50, 80, some long height]
topView frame == [80, 0, some long width, 50]
cellView frame == [80, 50, some long width, some long height]
i.e. the cell view will be indented by the height of the top view and the width of the left view. (I hope this makes sense).
So in your scrollViewDidScroll...
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
// we will transform the position of the top view and left view using the offset.
// I chose a transform as it always acts from the original position.
// changing the view's frame will make it difficult to set it back again.
CGPoint offset = [scrollView contentOffset];
// move the left view to the left and right depending on the offset
leftView.transform = CGAffineTransformMakeTranslation(offset.x, 0);
// up and down is taken care of by the scroll view correctly.
// move the top view up and down depending on the offset
topView.transform = CGAffineTransformMakeTranslation(0, offset.y);
// left and right is taken care of by the scroll view correctly.
}
I chose to use transform as it make the calculations easier. Instead of trying to calculate the difference in position required each time, you just set the transform amount to the offset and it works.
I have a UIScrollView which contains a UIView and a UITableView. My goal is to adjust the height of the UIScrollView to allow me to scroll the contents of the UIScrollView to a specific point.
Here is my view: It has a UIView up top and a UITableView down below.
When I scroll, I want the UIView to stop at a specific point like so:
The tableView would be able to continue scrolling, but the UIView would be locked in place until the user scrolled up and brought the UIView back to its original state.
A prime example of what I am trying to do is the AppStore.app on iOS 6. When you view the details of the app, the filter bar for Details, Reviews and Related moves to the top of the screen and stops. I hope this all made sense.
Thanks
I ended up going with a simpler approach. can't believe I didn't see this before. I created two views, one for the UITableView's tableHeaderView and one for the viewForHeaderInSection. The view I wanted to remain visible at all times is placed in the viewForHeaderInSection method and the other view is placed in the tableHeaderView property. This is a much simpler approach, I think than using a scrollview. The only issue I have run into with this approach is all my UIView animations in these two views no longer animate.
Here is my code.
[self.tableView setTableHeaderView:self.headerView];
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
return self.tableViewHeader;
}
add yourself as a UIScrollViewDelegate to the UITableView and implement the - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView so that if your views are in their starter positions they do this:
- your UITableView animates its size to the second state:
[UIView animateWithDuration:.1f animations:^{
CGRect theFrame = myView.frame;
theFrame.size.height += floatOfIncreasedHeight;
myView.frame = theFrame;
}];
- your UIView animates its vertical movement
[UIView animateWithDuration:3 delay:0 options:UIViewAnimationOptionCurveLinear animations:^(void){
view.center = CGPointMake(view.center.x , view.center.y + floatOfVerticalMovement);
}completion:^(BOOL Finished){
view.center = CGPointMake(view.center.x , view.center.y - floatOfVerticalMovement);]
Finally always in the delegate implement – scrollViewDidScrollToTop: so that you know can animate back to the initial state (using the same techniques reversed).
UPDATE:
since your views are inside a scroll view, there is a simpler way if you are ok with the table view being partly out of bounds in your starter position (i.e. instead of changing size it just scrolls into view):
make the scroll view frame size as big as your final tableview + your initial (entire) view and place it at 0,0 (so its final part will be hidden outside of the screen)
scrollview.frame = CGRectMake(0,0,tableview.frame.size.width,tableview.frame.size.height + view.frame.size.height);
you make the container scrollview contents as big as the entire table view + the entire view + the amount of the view that you want out of the way when scrolling the table view.
scrollview.contentSize = CGSizeMake(scrollview.frame.size.width, tableview.frame.size.height + view.frame.size.height + floatOfViewHeightIWantOutOfTheWay);
you place the view one after the other in the scrollview leaving all the additional empty space after the table view
view.frame = CGRectMake(0,0,view.frame.size.width, view.frame.size.height);
tableview.frame = CGRectMake(0,view.frame.size.height, tableview.frame.size.width, tableview.frame.size.height);
now it should just work because since iOS 3 nested scrolling is supported
You can easily achieve this by setting the content size of the scrollView correctly and keep the height of the UITableView smaller than your viewcontroller's height, so that it fits the bottom part of the top UIView and the UITableView...
Another scenario is to split the top View in 2 parts.
The part that will scroll away and the part that will be visible.
Then set the part that will scroll away as the entire UITableView header and the part that will remain visible as the header view for the first table section.
So then you can achieve this with a single UITableView, without having to use a UIScrollView
What you're looking for is something like what Game Center happens to do with it's header which can actually be modelled with a table header, a custom section header view, and some very clever calculations that never actually involve messing with the frame and bounds of the table.
First, the easy part: faking a sticky view. That "view that's always present when scrolling the table" implemented as a section header. By making the number of sections in the table 1, and implementing -headerViewForSection:, it's possible to seamlessly make the view scroll with the tableview all for free (API-wise that is):
- (UITableViewHeaderFooterView *)headerViewForSection:(NSInteger)section {
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0,0,320,50)];
label.text = #"Info that was always present when scrolling the UITableView";
label.textAlignment = UITextAlignmentCenter;
label.backgroundColor = [UIColor colorWithRed:0.243 green:0.250 blue:0.253 alpha:1.000];
label.textColor = UIColor.whiteColor;
return label;
}
Finally, the hard part: KVO. When the table scrolls, we have to keep the header up there sticky with regards to the top of the view's frame, which means that you can KVO contentOffset, and use the resultant change in value to approximate the frame that the view should stick to with a little MIN() magic. Assuming your header is 44 pixels tall, the code below calculates the appropriate frame value:
CGPoint offset = [contentOffsetChange CGPointValue];
[self.tableView layoutSubviews];
self.tableView.tableHeaderView.frame = CGRectMake(0,MIN(0,offset.y),CGRectGetWidth(self.scrollView.frame),44);
If the above is infeasible, SMHeadedList actually has a fairly great, and little known, example of how complicated it can be to implement a "double tableview". That implementation has the added benefit of allowing the "header" tableview to scroll with the "main" tableview.
For future visitors, I've implemented a much simpler version, albeit one that accomplishes the goal with Reactive Cocoa, and a little bit of a different outcome. Even so, I believe it may be relevant.
What if you break the UIView into the top and bottom. The bottom will be the info.
Set UITableView.tableHeaderView = topView in viewDidLoad
and the return bottomView as Section Header in delegate method to make it float:
(UITableViewHeaderFooterView *)headerViewForSection:(NSInteger)section
{
return bottomView;
}
Just using the UITableView can solve with your problem. it is not need to use another scroll view.
set your view as the header view of UITableView. Then add your present view to the header view.
complete - (void)scrollViewDidScroll:(UIScrollView *)scrollView; . Tn the function to check the contentoffset of scroll view, and set the present view's frame.
I have a scroll view with 3 UITableViews in it for paging. All of the UITableViews loads more cells of data. The first UITableView loads more cells than the other two. When viewing this first UITableView I am able to scroll to the bottom, but when I scroll to a second UITableView and back to the first UITableView I can no longer scroll all the way down. It seems as though I have to resize my scroll view. Why can't I scroll to the bottom after a view refresh? Any help would be great.
*The first UITableView has a search bar at the top. The other two do not. I tried removing the search bar, but the error still occurs.
//Create a frame for each page and add the page to the scroll view
- (void)frameToScrollView{
if (pages!=NULL) {
for (int i = 0; i < pages.count; i++) {
//Get the current view controller
UITableViewController *controller = [pages objectAtIndex:i];
//Create a frame for the current table view controller
CGRect frame = controller.view.frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
controller.view.frame = frame;
//Add the the current table view controller page to the scroll view
[self.scrollView addSubview:controller.view];
}
}
}
Set Other properties:
//Set the properties for the scroll view
- (void)setScrollViewProperties{
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width * pages.count, self.scrollView.frame.size.height);
self.scrollView.contentOffset = CGPointMake(self.scrollView.frame.size.width, 0);
self.scrollView.scrollsToTop = NO;
}
UITableView is a subclass of UIScrollView. So you are basically adding 3 scrollviews to a scrollview. I dont think this is advisable.
I think the problem here is that the device is confused as to which scrollView will handle the touch/drag event.
If you really need the scrollView for paging, I suggest you create the scrollView, but disable touch event for this. You can add buttons to allow page navigation (instead of allowing user to do left/right swipe). This way, you can ensure that only the tableview that is visible is going to get the touch/drag event.
Found similar problem here: UITableView Won't Scroll In Certain Conditions.
My first UITableView has a search bar at top.
In the post above they recommend adding [self.tableView setAlwaysBounceVertical:YES];
I tested this and it does not work. I put it in my view did load for the UITableView.
Got it working:
(1) After "load more" cell is clicked and information is received I remove all subviews
(2) Then I create new frames and add them back to the subview
(3) Last I reload the table data