Generally:
Is it OK to add a UITableView as a subview of another UITableView? Or, should I create a UIView and add each UITableView to it?
Specifically:
For a ComposeTableViewController with a typeahead, like in the iPhone's native Mail app, which approach would you recommend and why?
Note: I prefer to construct things 100% programmatically (no Interface Builder).
Subclass UITableViewController.
Then, to show the typeahead results, create and add a resultsTableView as a subview of self.tableView positioned directly underneath the the cell (of self.tableView) with the typeahead text field.
The nice thing about this approach is that resultsTableView scrolls with self.tableView automatically.
But, is it OK to add a UITableView as a subview of another UITableView?
Subclass UIViewController.
Create and add tableView (custom property) as a subview of self.view.
Create and add resultsTableView also as a subview of self.view.
The annoying thing about this approach is that I have to reposition resultsTableView manually anytime self.tableView scrolls.
I think I'd prefer approach 1, but adding a UITableView as a subview of another UITableView just seems smelly to me.
TableViews cannot have subviews. You can try adding a tableview as the view of a TableViewCell, but then you have to ask yourself how it would scroll, if you tried scrolling in the subtableview would it scroll the child tableview or the parent tableview? It is much easier to present multiple tableviews within a view. This can be done easily by setting your custom viewcontroller as the datasource of both tableviews contained within its view and then comparing the tableview pointer that is sent as a parameter of the datasource method to the two tableview pointers that are IVars of your custom view controller.
Hold stuff like this in a container. Create a container view controller which only does typeahead. This container view controller will hold your main table view controller (and its table view) and it will hold the typeahead view controller (and its view).
It will keep the logic needed for the typeahead out of your main table view and as a bonus you might end up with a reusable typeahead container which could be applied to other views.
Yes it is good to go for adding UITableView in as a cell of another UITableView.
I had one issue and posted a question
Multiple Views as subviews
And requirement was like a group of controls with list of other controls. I thought that time that it will be messy if i'm going to add UITableView as a cell of UITableView.
What i found that... Boy !! it's how iOS meant to be. There is no any lag while doing this.
Tested for below functionalities:
Scrolls like a charm
Separate delegates called for each
Reordering of both UITableView cell
Swipe and remove cell
Runtime datasource update for both UITableView and reload both at the same time.
There is no any reason not to add subview UITableView.
You can do it but it is against the principle of MVC. You will be setting the delegate of a view to another view which is wrong.
Related
I'v never used UITableViewControllers or UICollectionViewControllers, because you can have the same functionality by using UIViewController with its root UIView, then adding UITableView in xib or storyboard and assigning its delegate and datasource. And I also was able to put activity indicator inside the center of root UIView.
Now the things get a little bit complicated when using UICollectionViewController where its root view is UICollectionView. I need to update some code of other guys and they put activity indicator inside UICollectionView (in storyboard). The problem is this activity indicator gets hidden when cells are reused because activity indicator view is the most bottom one. I was unable to change visibility priority storyboard and also this code in view didLoad is not working:
[self.itemsCollectionView bringSubviewToFront:self.activityIndicator];
Because labels, images and etc. views of collection view cell are placed later, during collectionView:cellForItemAtIndexPath:. I could try to call bringSubviewToFront: in collectionView:cellForItemAtIndexPath: but that would be a wrong decision. Any ideas how to achieve this when using UITableViewControllers or UICollectionViewControllers?
IMHO the only reason to use UITableViewControllers or UICollectionViewControllers is because static cells are not shown storyboards when designing layout.
UPDATE It appears iOS wraps UICollectionView inside UICollectionViewControllerWrapperView. Tried to add activity to this wrapper view in viewWillAppear:
[self.itemsCollectionView.superview addSubview:self.activityIndicator];
But with no luck - activity indicator is still is below the cells.
I'v ended in refactoring existing UICollectionViewController in storyboards: I'v opened storyboard xml file with TextEdit, searched for the screen and changed its type from collectionViewController to viewController because was unable to find another way how to change the type of controller, though I hope there will appear some more elegant way for that in the nearest future. Then, I'v wrapped collectionView inside root view and placed activityIndicator inside this view. It's proven classical approach that works like a charm.
I'm trying to change the size of a tableView I have in interface builder and can't seem to. When I first started the app I could drag it around and stretch the sides but all of a sudden I can't adjust it. I tried to delete my tableView and add a new one but the same thing happened. Thanks in advance. Here's what I see when I try to change the size:
if your using a UIViewController you can drag and drop a tableView and can place in a custom position you want. but if your using a UITableViewController you cant move the tableView to your custom position. if you want to do it in UITableViewController you can do like below
if you want your tableView content should show from a point, that you want you can do this way,
[self.tableView setContentInset:UIEdgeInsetsMake(100,0,0,0)];
else if you want set your tableView to a frame in UITableViewController you do this way,
- (void) viewWillLayoutSubviews
{
[super viewWillLayoutSubviews];
self.tableView.frame = CGRectMake(0,100,320,300);
}
hope this will help you.
What kind of view controller are you using to manage your table view? Since you show "prototype cells", I'm guessing it's a UITableViewController. Those are built to fill the entire screen with a single table view (which has always annoyed me.)
Starting with iOS 6, though, you can create a "container" view in another view controler, and then drag an embed segue from your container view onto the table view controller. That does all the housekeeping to make the table view controller a child view controller of the other one, and then you can make it whatever size you want.
If you don't want to use a UITableViewController as a child of another view controller, you can use a regular view controller and wire up the data source and delegate methods yourself. However, things like static table views and prototype cells don't work then.
Hopefully this helps someone still coming across this problem. What I did was make sure the UIViewController had a UIView as its direct child, then dragged the UITableView as a child of the UIView, this allowed me to resize the UITableView.
UPDATE (SOLVED ALREADY) :)
I tried to recreate my scene from scratch. And I found out that if the Class of the table view controller is "UITableViewController", the repositioning of view when keyboard appears happens properly. But when I set the Class of the table view controller to my custom class, the repositioning doesn't happen. Why is this so? Given that my custom class is a subclass of UITableViewController and nowhere in my implementation did I implement any data source and data delegate since I am using static cells?
I forgot to add the delegate in my interface declaration. Now it's working already.
#interface CustomClass : UITableViewController <UITableViewDelegate>
I have a UITableViewController where the tableview content is static cells and style is plain. I added 7 table view cells. In each cell, I added a text field.
When I click on a table view cell, the keyboard shows but the table view did not reposition; thus hiding the table view cell that I selected.
I have solved this before but I was using a view controller then which I embedded inside a scrollview. But seeing from documentation, UITableViewController, which has a scrollview by default, is supposed to automatically resize and reposition it's table view.
I am working on XCode 5 and using iOS 7 latest version.
You can change the offset (y) of the tableView whenever textField's action is didBeginEditing.
If you need any more help let me know ;D
It should automatically change its size, but not necessarily adjust its position/offset.
Are you sure the table view still covers the entire screen, even below the keyboard?
You can check this by scrolling and looking at the scrollbars.
If you want to adjust the content offset, do so in the callback when the user begins editing the text field.
Eliminate the code that sets the content offset of the table view.
The table cell for text field with the first responder status should automatically scroll above the keyboard. You shouldn't have to write a lick of code for this.
If you are using static cells, make sure that your table view controller does not implement the table view data source methods. Also, the view controller that you dragged onto the IB canvas must be a UITableViewController; it can't be a UIViewController that contains a UITableView dragged from the objects library.
After thorough checking, I realised, my custom class only subclass UITableViewController without adding the delegate :(
below solves the problem... at last! :)
#interface CustomClass : UITableViewController <UITableViewDelegate>
I'd like to have the section header (for an UITableView) for the uppermost cell only , a sort of header for the table that sticks to the top, showing some additional information about the uppermost cell.
is it somehow possible? if not (as I suppose since I've carefully read all the documentation) do you have any idea how to replicate this behaviour?
You need to create your own view to use as the header. It will be simplest to make your custom header view be a sibling of the table view, and position it so that it's above the table view on the screen.
Since UITableView is a subclass of UIScrollView, your table view's delegate is also a scroll view delegate and receives the UIScrollViewDelegate messages. You want to implement this method:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
Each time your delegate receives that message, you want it to look at which table view row is at the top of the table view (using [tableView indexPathForRowAtPoint:tableView.contentOffset]) and update the contents of your custom header view accordingly.
Read the Apple documentation for UITableView. The property you're looking for is tableHeaderView.
This is hard (not impossible) with UITableViewController because it forces the tableView to be the root view.
If you implement your own controller, inherit from UIViewController instead of UITableViewController.
You must adopt the data source and delegate protocols, and implement the methods appropriately, but then you have a normal view as your root view. You can then add a UITableView in any location and size you want, with anything you want around it.
The only real restriction is static table views you build in IB. However, in that case, you can implement view controller containment, and just parent your table view controller into another controller, and give it a specific view to take over.
The first option is dead simple, but the second is an advanced technique, and you need to understand view controller containment to do it right.
Here is my app.
http://www.flickr.com/photos/baozhiqiang/6943921630/
http://www.flickr.com/photos/baozhiqiang/6943921900/
You can see three buttons at the top of the main screen. When you click it, the gallery will change to next. They are not the same layout style.
I created it by making three ScrollView in a big ScrollView. Code like this:
[backgroundScrollView addSubview:innerNewsScrollView];
[backgroundScrollView addSubview:innerHotScrollView];
[backgroundScrollView addSubview:innerLinkScrollView];
And when click the button, I changed the frame of the ScrollView.
Now there is a problem, when I add more than 100 Pictures(UIButton with image) to the ScrollView, It had crashed. I want to use UITableView replace ScrollView. But how can I Control more than one UITableView in a UIViewController?
Anybody can help me!
Two possibilities:
All the table view delegate methods include the table in question as one of the paramters, so it would simply be a case of checking which table is requesting data/information
You don't have to point your table views to the view controller. Your view controller could store two objects whose only purpose is to repond to table view delegate methods
Unless the tables are trivial, I think the second option is the cleanest.
Add all of your UITableViews in the UIViewController's view, set their tag properties to something you can distinct them and also set their delegates (usually self if your UIViewController implements the UITableViewDelegate protocol). Every method in the UITableViewDelegate passes UITableView reference as an argument and with the value of the tag property you can find out which table view is processed.