If while scrolling header section in UICollectionview rose above navigationitem how can I know the index of the header section which is not visible?
You can use view.window property if its nil it means its not visible.
Since Collection view re-uses views you would like to check which last header view is visible
instead and subtract one .
1) For the UIViews which are visible get the min index.
2) All the view above it are not visible.
Related
I'm working with UICollectionViewController. At some point In need to make some configurations to the visible footers and for each one of them, I need to know its' current section number. Current because sections may be replaced and the section of a reusable view may change.
self.collectionView.visibleSupplementaryViews(ofKind: UICollectionView.elementKindSectionFooter)
.filter { $0.reuseIdentifier == reuseIdentifierFooter}
.forEach {
// Here I need to know the section number of each view
}
Get the index path for the visible views: https://developer.apple.com/documentation/uikit/uicollectionview/1618034-indexpathsforvisiblesupplementar
Then iterate through the indexPaths and query the view with https://developer.apple.com/documentation/uikit/uicollectionview/1618041-supplementaryview
In my code I have a stack view that initially has 1 element PhoneNumberField. Another PhoneNumberFieldscan be added dynamically in the runtime:
#IBAction func addAlternatePhoneNumberAction(_ sender: UIButton) {
let alternateNumberView = PhoneNumberField()
...
phoneNumberStackView.addArrangedSubview(alternateNumberView)
}
This is what xib for PhoneNumberFieldlooks like:
The problem is that I would like to be able to dynamically hide the 'Name for other phone' field based on the content of 'Mobile combobox'. When I set the 'isHidden' parameter everything works as expected, the only problem is that the PhoneNumberField height stays the same. I would like it to shrink when the 'Name for other phone' field is hidden.
I tried doing it using the outlet for height constant for otherNumberNameField in the PhoneNumberField.swift file but the problem is that in that case all of the PhoneNumberFields in the stack view have the size of the first field.
What would be the correct solution for this?
edit: In addition to the answer below: I had to set the distribution for the phoneNumberStackView to equal spacing. Worked like a charm.
First, create StackView.
Don't set its height constraint, just set top, leading, trailing and bottom constraints.
Bottom constraint set equal to Error label top constraint.
Then set its distribution to Fill Equally.
Now put first two Views into one view and put this view together with OtherNumberField view to this StackView.
So now your hierarchy should look like this:
Now when you hide one view from StackView, StackView will be smaller because you didn't set its height.
i have a stackview desing in storyboard with 5 view inside composed of 1 buttom, a small view with a label and a button. like this.
what i want is to remove one of the the view let say the one with orange background.
i tried this on viewdidload
stackview.view2.isHiden = true
stackview.view2.removeFromSuperview()
this remove the view and all elements but the remaing does not distribute as expected any idea how to achive this
// Appears to remove the first arranged view from the stack.
// The view is still inside the stack, it's just no longer visible, and no longer contributes to the layout.
let firstView = stackView.arrangedSubviews[0]
firstView.isHidden = true
I have a custom UITableView header which I want to be able to scroll above the top of the table. Normally the header would stick to the top of the table, is it not possible to somehow change to scrolling ability so that it can go beyond that and scrolls with the cells in the table?
Thanks.
Well if that is the desired behavior you want, just put the header as the first cell's content. It is possible to customize any particular cell you want. UITableViewDelegate documentaion will help you in that matter.
PS: the whole point of using tableView header is to make it stick to the top of the window.
EDIT: If it is necessary that you have to do the way you want, then you can try this: move your tableView a little down by setting its contentOffset. eg: myTableView.contentOffset= CGPointMake(0,heightOfYourView) . Now add yourView at the top
myTableView.tableViewHeader = myCustomTableHeaderView;
This would set myCustomTableHeaderView as the header of your table view and it would scroll with the table view.
By implementing tableView:viewForHeaderInSection: for section of index 0, you can instead have the header as the first section that should disappear when it scrolls. In this way, it's not a header for the whole UITableView.
If you only have one header for the whole table, can't you just set the tableHeaderView property?
You might, like me, have been searching for the tableHeaderView property. See this SO question for more info.
You should use Grouped TableView Style and in your ViewDidLoad method, add following line of code:
myTableView.backgroundColor=[UIColor clearColor];
myTableView.opaque=NO;
myTableView.backgroundView=nil;
Also in nib file, you should clear background color of grouped table;
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGFloat sectionHeaderHeight = 40;//Change as per your table header hight
if (scrollView.contentOffset.y<=sectionHeaderHeight&&scrollView.contentOffset.y>=0) {
scrollView.contentInset = UIEdgeInsetsMake(-scrollView.contentOffset.y, 0, 0, 0);
} else if (scrollView.contentOffset.y>=sectionHeaderHeight) {
scrollView.contentInset = UIEdgeInsetsMake(-sectionHeaderHeight, 0, 0, 0);
}
}
I need to set custom section height for my table view, and I'm trying to do it in pretty straightforward way by calling some delegate method:
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
return 39.0;
}
I do get desired result - a taller section but I'v noticed one problem. When I tap the table (start dragging), move my finger up to top, and release the table, then the table bounces back but does not return to the correct initial place. If What I mean is the section header overlaps the first row. Here is the screen:
Any ideas why this happens or what workarounds exist?
UPDATE: I also tried increasing section height property of the tableView in IB. This increases the height but the same problem exist.
It sounds like you're dragging the table up so that the last row of the table, plus empty space below it, is showing, like this:
When you let go, it slides the table back down so that bottom edge of the last table row is flush against the bottom edge of the view.
This is the expected behavior for a table view. You're seeing the top row slip partly underneath your section header because the view height, minus the section header height, isn't an integer multiple of the row height. If you don't like this, you need to make sure the view height minus the section header height is an integer multiple of the row height.
There is another way to set the section height without using the delegate:
self.tableView.sectionHeaderHeight = 39.0;
If this does not help, you will have to fiddle with the UIScrollView Delegate.
Also, from your screen shot I see that you might be interested in the property tableHeaderView, which is a header above the table that will scroll off-screen when the table view is scrolled.