I have a mockup that looks like this:
This is all one big Table Controller that you can scroll.
When the section header hits the top of the page it freezes along the top, like so:
Which is working fine. However, when you go back to the top and do a pull to refresh, I want it to do this:
So the pull to refresh dialog appears between the top table header cell and the section header (that is no longer frozen).
Is this possible? I haven't found an implementation like this in my searches.
You can do the following to achieve this,
Add a UIScrollView as the subview of UIViewController's view.
Add a UIView and UITableView as the subview of this scroll view
UIView inside scroll view represents table header cell.
Section header can be the header of UITableview and table contents represents the UITableView's cells.
Add UIRefreshControl as subview of UITableView and set its target method.
Implement the scrollview delegate - (void)scrollViewDidScroll:(UIScrollView *)scrollView for both UITableview and UIScrollview.
When you are scrolling the tableview, move the parent scrollview whenever the table view header moves in the upward direction till the header reaches the top. Add an if condition in scrollview delegate to check for this.
When the table view is moved the downward direction, move the parent scrollview until the UIView table cell header is visible after this stop scrolling of UIScrollview and allow table view to scroll. This will enable the UIRefreshControl.
Here the key thing is the - (void)scrollViewDidScroll:(UIScrollView *)scrollView method and how you implement the scrolling. You can add a check for contentOffset to determine how much tableview and scrollview has been scrolled. In order to restrict the scrolling you can manually set this value in this delegate method to a particular value and it wont scroll after that.
Related
I'm developing an app and I need a view with these elements:
- UITableView
- UITextField and UIButton
- TabBar
As you can guess, I am developing a chat, but when I put the elements in the .xib, I can't show de layer: UITextField and UIButton. If I put them without a view, they dont appear.
If I put a view under the table, and in that view I put the text and the button I get this error: http://pastebin.com/CKfxijz9 (I put the error there because it's to long)
Thanks in advance
There are some ways of dealing with that, depending on how it should behave. Some of them are:
Provide a table footer or header view that holds the button and
the text field.
Nest the table view into another view. The table
view and the view containing the button and text fielt are on the
same level within the view hierarchy. They are rather siblings than
sub- and superview to each other.
Use a UISlider instead of a table. (However, I personally would use the table.)
Here's an approach I've used in the past (not sure if it's best practice, but it works).
Add your button and textfield to a new view (let's call it, bottomView)
Add bottomView to the superview of your tableview
Set the frame of your bottom view so that it fits to the bottom of the screen (this will make it so your tableview will scroll, but keep your bottomView always attached to the bottom of your mainview)
I'm trying to add a UIView on top over the UITableView to mimic the iPhone Facebook style menu. I have it working fine by making the controller a UIViewController then adding a tableview however I am unable to make the menu a static menu unless the controller is a UITableView.
Is it possible to add a view ontop of a tableview and only make the tableview in the background scrollable without the view in the foreground scrolling?
Here is what I have with the subclass being UIViewController
But I am unable to make the tableview cells static via IB since it is not a subclass of UITableView Controller.
EDIT per NSJones Code:
It seems to be going somewhat in the right track. However the view still blocks the table. If I remove the view from the storyboard it will only display the table.
You can make a view hover the same way you make any real thing hover; Hold it up with something invisible.
Basically what you want to do is create a clear UIView (with user interaction disabled) that is the size of your view controller's view, and add it as a subview to your view controller's view property. That way it sits invisibly on top. then you can add a subview to that clear view and that subview won't move.
Edit:
It seems this nice clean approach won't work for you since you need your view controller to be a UITableViewController. The answer for this slightly more complex approach is to use a delegate method for UIScrollView which also works for UITableView. Apple has a fantastic demo of this concept in the WWDC2011 - Session 125 - UITableView Changes, Tips, Tricks video. If you can watch it I highly recommend it. The meat of this issue begins at about 36:10.
But to sum it up you implement the scrollViewDidScroll: delegate method. And handle the movement of the tableview by adjusting the position properties of the view. Here I am keeping an UIView property named viewToKeepStill still using this method.
-(void)scrollViewDidScroll:(UIScrollView *)scrollView{
// CGFloat stillViewDesiredOriginY; declared ivar
CGRect tableBounds = self.tableView.bounds; // gets content offset
CGRect frameForStillView = self.viewToKeepStill.frame;
frameForStillView.origin.y = tableBounds.origin.y + stillViewDesiredOriginY; // offsets the rects y origin by the content offset
self.viewToKeepStill.frame = frameForStillView; // set the frame to the new calculation
}
Instead of adding it as a subview of the table view, add it as a subview of the superview of the table view; that way it won't scroll.
So instead of this:
[tableView addSubview:viewController.view];
Do this:
[tableView.superview addSubview:viewController.view];
Assuming you want something that is visible full-time with the table, start with a view which contains both the menu view and the UITableView. Make the table smaller so it ends where the menu view begins. The table view can work with less vertical space.
If you have your UIViewController's view to be your table view then your table is going to span over the whole screen, so you won't be able to add anything on top of it.
Why not try the following:
1) create a new UIViewController
2) add a view on top where you want your menu
3) in the space left under just drag a table view from the component library
4) don't forget to set the 2 table view delegates to be your view controller class
that's about it?
I have 2 table view, with the same number of cells.
Could you please point me the correct way, that I could implement simultaneous scrolling. I mean, when I scroll through one table, the other one is scrolling the same time. Thanks.
As uitable view is derived from uiscrollview you can get the scroll amounts in the delegate method
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
You can get content offset of the scrollview which is being scrolled and assign that to the other tableview.
In this method you should be able to access both tableviews.
The property you need to check is contentOffset.
firsttableview.contentOffset = scrollview.contentOffset
The "too long; didn't read" version: Is there any way to disable the automatic scrolling behaviour of UIScrollView when telling a UITextField to becomeFirstResponder?
I have a scroll view with paging enabled and several views as subviews, each subview being controlled by its own view controller. Each subview has a UITextField.
The requirement is that when a page is scrolled into view, it's text field should become first responder.
This is fine when using finger swipes to scroll -- I use the scroll view delegate method scrollViewDidEndDecelerating: to know when scrolling stops and a page is in view, I can tell the text field to become first responder.
However, when the scroll view is "autoscrolled", as in when telling the scrollview to scrollRectToVisible:animated:, the scroll view delegate method for deceleration isn't called. I use this method when scrolling newly created pages into view without the user's interation, or when the user taps the UIPageControl.
My solution was to simply set the first responder status of the text field before telling it to scroll into view - but it seems that telling a text field that is in a scroll view to become first responder causes the scroll view to automatically scroll it into view.
I assume this is behaviour used when putting text fields in table view cells (since table views are scroll view subclasses). If you set up a small test app, with a table view, and a text field within a table cell, if the keyboard would obscure the table view cell when it becomes first responder, the table view will automatically scroll it to be visible.
I don't understand, though, why this behaviour occurs in my example, where I'm not using a table view - just a plain scroll view.
I should also mention that my scroll view has vertical scrolling disabled and only scrolls horizontally.
I have tested in another test app that puts text fields as direct subviews of a scrollview (no view controllers or container views) and the same happens. If you tell a text field that is offscreen to become first responder, the scroll view with automatically scroll it for you.
This wouldn't normally be a problem, but it seems to screw up the paging of the scroll view. When I scroll with my finger, each view bounces and is centred properly. But when I scroll a rect to be visible with animation and tell a text field to become first responder, scroll view seems to become conflicted with itself and the view is only scrolled part of the way into view, and isn't centred.
Then, if I touch a view using my finger (not swipe, or even move), the scroll view jumps back to the first page.
My current work around for all this silly auto scrolling behaviour is to use an NSTimer to determine when to update the first responder.
I do the manual scrolling in code using scrollRectToVisible:animated and then after 0.3 seconds, call my method to update the text field to be first responder. (0.3 seconds was trial and error, trying to see which seemed to be the smallest amount of time to allow for the animation but still be long enough not to cause the conflict with the scrollview.
As you can see, this isn't elegant, and is likely to break.
Is there any way to disable the automatic scrolling behaviour of UIScrollView when telling a UITextField to becomeFirstResponder?
Call becomeFirstResponder, then right away, set the contentOffset of the scrollview to its current position..
[textField becomeFirstResponder];
[scrollview setContentOffset:scrollview.contentOffset animated:NO];
Not an answer to your question, but it should fix the problem:
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView
{
// Make the text field first responder...
}
I am populating a UITableViewController's UITableView through code only. At the bottom of the table I wish to position a button that scrolls into view as the user scrolls to the bottom of the table.
When in the UITableViewController life cycle should I populate the table footer with a button? viewDidLoad?
p.s. I wish to avoid using section footers in the UITableView.
Yes, viewDidLoad is the correct place. It's not a stone-set rule though - I have change footer view in many different situations, such as after rotation in didRotateFromInterfaceOrientation.
Note that the view will be repositioned to location immediately below the last row, so if you want to provide a margin or centering for your button I suggest adding a plan UIVIew as footer, and then add your button(s) into that UIView.
Yes, put it in viewDidLoad. Here is some sample code.
You can just set the tableFooterView property of a UITableView to your button.