Mixing
Scroll a UIViewController to the top just like it is done when clicking on the iOS Status Bar
0
I would like to know if the method that Apple uses to scroll a UIViewController that contains a UIScrollView to the top when the user taps on the status bar is available to us.
I tried to find it, but I had no success.
I tried to reproduce it, but it did not work 100% when the UIViewController prefers to display large title (the large title is not expanded).
How can we scroll a UIViewController to the top just like Apple does?
Follows my trial:
extension UIViewController {
private var firstScrollView: UIScrollView? {
var scrollView: UIScrollView? = nil
var viewsToCheck = [self.view]
while !viewsToCheck.isEmpty && scrollView == nil {
let viewToCheck = viewsToCheck.remove(at: 0)!
if let viewToCheckAsScrollView = viewToCheck as? UIScrollView {
scrollView = viewToCheckAsScrollView
} else {
viewsToCheck.append(contentsOf: viewToCheck.subviews)
}
}
return scrollView
}
func scrollToTheTop(animated: Bool) {
if let firstScrollView = firstScrollView {
firstScrollView.scrollRectToVisible(CGRect(x: 0, y: 0, width: 1, height: 1), animated: true)
}
}
}
ios tableview scrollview
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
|
show 1 more comment
0
I would like to know if the method that Apple uses to scroll a UIViewController that contains a UIScrollView to the top when the user taps on the status bar is available to us.
I tried to find it, but I had no success.
I tried to reproduce it, but it did not work 100% when the UIViewController prefers to display large title (the large title is not expanded).
How can we scroll a UIViewController to the top just like Apple does?
Follows my trial:
extension UIViewController {
private var firstScrollView: UIScrollView? {
var scrollView: UIScrollView? = nil
var viewsToCheck = [self.view]
while !viewsToCheck.isEmpty && scrollView == nil {
let viewToCheck = viewsToCheck.remove(at: 0)!
if let viewToCheckAsScrollView = viewToCheck as? UIScrollView {
scrollView = viewToCheckAsScrollView
} else {
viewsToCheck.append(contentsOf: viewToCheck.subviews)
}
}
return scrollView
}
func scrollToTheTop(animated: Bool) {
if let firstScrollView = firstScrollView {
firstScrollView.scrollRectToVisible(CGRect(x: 0, y: 0, width: 1, height: 1), animated: true)
}
}
}
ios tableview scrollview
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41
|
show 1 more comment
0
0
0
I would like to know if the method that Apple uses to scroll a UIViewController that contains a UIScrollView to the top when the user taps on the status bar is available to us.
I tried to find it, but I had no success.
I tried to reproduce it, but it did not work 100% when the UIViewController prefers to display large title (the large title is not expanded).
How can we scroll a UIViewController to the top just like Apple does?
Follows my trial:
extension UIViewController {
private var firstScrollView: UIScrollView? {
var scrollView: UIScrollView? = nil
var viewsToCheck = [self.view]
while !viewsToCheck.isEmpty && scrollView == nil {
let viewToCheck = viewsToCheck.remove(at: 0)!
if let viewToCheckAsScrollView = viewToCheck as? UIScrollView {
scrollView = viewToCheckAsScrollView
} else {
viewsToCheck.append(contentsOf: viewToCheck.subviews)
}
}
return scrollView
}
func scrollToTheTop(animated: Bool) {
if let firstScrollView = firstScrollView {
firstScrollView.scrollRectToVisible(CGRect(x: 0, y: 0, width: 1, height: 1), animated: true)
}
}
}
ios tableview scrollview
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
I would like to know if the method that Apple uses to scroll a UIViewController that contains a UIScrollView to the top when the user taps on the status bar is available to us.
I tried to find it, but I had no success.
I tried to reproduce it, but it did not work 100% when the UIViewController prefers to display large title (the large title is not expanded).
How can we scroll a UIViewController to the top just like Apple does?
Follows my trial:
extension UIViewController {
private var firstScrollView: UIScrollView? {
var scrollView: UIScrollView? = nil
var viewsToCheck = [self.view]
while !viewsToCheck.isEmpty && scrollView == nil {
let viewToCheck = viewsToCheck.remove(at: 0)!
if let viewToCheckAsScrollView = viewToCheck as? UIScrollView {
scrollView = viewToCheckAsScrollView
} else {
viewsToCheck.append(contentsOf: viewToCheck.subviews)
}
}
return scrollView
}
func scrollToTheTop(animated: Bool) {
if let firstScrollView = firstScrollView {
firstScrollView.scrollRectToVisible(CGRect(x: 0, y: 0, width: 1, height: 1), animated: true)
}
}
}
ios tableview scrollview
ios tableview scrollview
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
edited Jan 3 at 8:02
Augusto Carmo
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
asked Jan 2 at 15:59
Augusto CarmoAugusto Carmo
863420
863420
The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41
|
show 1 more comment
The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41
The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41
|
show 1 more comment
1 Answer
1
active
oldest
votes
0
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
answered Jan 2 at 16:29
mattmatt
333k46544742
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
answered Jan 2 at 16:29
mattmatt
333k46544742
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
add a comment |
0
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
answered Jan 2 at 16:29
mattmatt
333k46544742
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
add a comment |
0
0
0
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
answered Jan 2 at 16:29
mattmatt
333k46544742
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
answered Jan 2 at 16:29
mattmatt
333k46544742
edited Jan 2 at 16:35
answered Jan 2 at 16:29
mattmatt
333k46544742
answered Jan 2 at 16:29
mattmatt
333k46544742
answered Jan 2 at 16:29
mattmatt
333k46544742
333k46544742
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
add a comment |
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
Thank you for your contribution, @matt. But this code is having the same behaviour as the one that I posted. In case the UIViewController prefers to display large title, when the scrolling is done, the large title is not expanded =/.
– Augusto Carmo
Jan 3 at 8:10
add a comment |
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The behaviour you describe is a native behaviour if you are using a UIScrollView subclass (UITableView or a UIScrollView). It's working for me without adding any additional code.
– Mourad
Jan 2 at 16:10
@Mourad is there any way that I can call it? I want to do it programatically.
– Augusto Carmo
Jan 2 at 16:14
can you please explain? when clicking on the iOS Status Bar nothing happend to me . You mean swipe down from top of status bar to see notification?
– user1376400
Jan 2 at 16:22
The method you are using 'scrollToTheTop' is correct. But i think that your problem is due to the implementation you are doing to get the UIScrollView instance. I think that your while loop is not working, because the 'viewsToCheck' variable is not instantiated properly. I think that it should be initialized with self.view.subviews and not just self.view (I suppose that your UIScrollView instance is added as a subview to your UIViewController's view) I hope this helps.
– Mourad
Jan 2 at 16:32
You do not explain what “but it did not work 100%“ means, so those words are meaningless. When you use your code what happens?
– matt
Jan 2 at 16:41