Add a UIView over the top of UITableViewController in Swift - ios

I currently use a UITableViewController (PFQueryTableViewController), I would like to display a UIView over the top of the TableView.
Ideally I'd like to do this in the storyboard, so I can easily add additional Labels/buttons to it. However, I can't seem to figure out how or if you can do it in storyboard. Is that right?
I have tried it programmatically. I first created the variable at the top:
var filterLabelView:UIView = UIView()
I then added the following in ViewDidLoad :
filterLabelView.frame = CGRect(x: self.view.frame.width/2, y: self.view.frame.height/2, width: self.view.frame.width, height: 40)
filterLabelView.center = CGPointMake(self.view.frame.size.width / 2, self.view.frame.size.height / 2)
filterLabelView.backgroundColor = UIColor.redColor()
self.view.addSubview(filterLabelView) // See below
I also tried:
self.view.insertSubview(filterLabelView, aboveSubview: tableView)
This creates the red UIView, but it seems to be embedded to the tableview, as when I scroll up and down, the View moves with it.
What I want to create
Ideally, I want the view to sit at the bottom of the screen, and not move when the user scrolls. An example screenshot of how I want it look is below:
I have read that the best way is to use a UIViewController with a UITableView inside it, but I'd rather not take that approach seeing how much my app is already built up.
Can anyone help me create this look? Thanks in advance

You have to derive from UIViewController to get full layout control.
Then simply add a UITableView instance in Storyboard. Constrain it normally, edge-flush, top-flush, and have customView.top = tableView.bottom. Make a normal outlet to your controller.
You just need to remember to make your custom UIViewController adopt the usual dataSource and delegate protocols, as well as assigning itself as those roles to the properties of the UITableView on initialization (usually viewDidLoad()).
There's one more finesse related to clearing the selected cell when on viewDidAppear(), but there's nothing else special about a UITableViewController -- it's just a UIViewController with a built-in tableView property and automatically assigned delegates and a very inflexible layout.
ADDENDUM based on comment about how to get around this: It's sort of like asking if there is any way to make a screwdriver drive a nail into wood. Just use the right tool. The top-level view property of a UITableViewController is the UITableView itself. See below, a stock UITableViewController with nothing else, zero code, in layout debug mode.
This means the entire tree of views is embedded in a scrolled entity, so all subviews will scroll with it.
It really shouldn't be that big a deal to re-do this one VC in Storyboard. After all, your rendering code in cellForRowAtIndexPath and your dataSource and delegate generally, don't change at all.
ADDENDUM 2:
Not knowing Parse intimately, this may not be possible. (!! Thanks, Parse.) If Parse doesn't supply you with a separable PFQueryTableView that you can embed yourself, the following workaround may be possible, but you'll need to understand the Objective-C code:
https://www.parse.com/questions/pfquery-tableview-for-uiviewcontroller

Related

How to access custom view properties after initialize

I'm targeting IOS 8+.
I have a form that is used in more than one place. So I decided to create a custom view where I define the various "form" text fields.
I have built my XIB, and the UIView subclass contains the outlets for each textField.
The view is composed of a background image and a scroll with the form fields over it.
Now, my first obstacle was: I need to have this custom view in a container that may or may not have a navigation bar. This made me create a constraint outlet so I could update its value to push down the scroller view. This way I'd have the whole image in the frame, the top being behind the navbar and the scroller bellow the nav bar).
Here's a manual drawing to help understanding the problem.
It's very possible that I'm making a lot of mess and confusion on my way to solve this. :)
The problem is:
After awakeFromNib runs I have no access to the constraint property. I then noticed the same thing happens for the TextFields outlets.
So, how can I access the custom view's properties when I instantiate them programatically?
Something like:
Controller:
let customView = SignupView(frame: f)
view.addSubview(customView)
customView.pushScrollerDownBy(50.0)
Custom view:
func pushScrollerDownBy(yOffset: CGFloat) {
//topScrollerConstraint is the outlet for the textField.
topScrollerConstraint.constant = yOffset //right now topScrollerConstraint is nil.
}
You should check if you have connected your topScrollerConstraint to the file's owner since it will not get instantiated and therefore, error. Here is a recent SO question regarding difference between these two:
What is File’s owner in XIB in this case?

Design iOS View in Code without storyboard

I want to design and generate view elements in code, without using storyboard. But I haven't figure out a simple way to locate where should I put my view elements by describing its CGRect. For example, I can drag a button direct into the storyboard and put it where i want, however, in code, I have to write something like
[button setFrame:CGRectMake(24.0f, 113.0f, 271.0f, 140.0f)];
Is there any way or any software can help me?
Your question is a bit broad. You can create your view in code by including in your subclass of UIViewController properties for each subview (control) element and then make all the initialisation in designated initialiser and setting frames and other customisation in viewDidLoad method most likely. But for details where to what set you should go to references for UIViewController lifecycle as it may depend on what you want to achieve. in some cases setting frames in viewDidLoad will be fine whereas sometimes you will need to make some changes in viewDidLayoutSubviews for example.

How are NSTableCellViews supposed to be laid out?

I have a fairly basic MainWindow.xib with a source list-style sidebar. I created it by dragging the Source List template into the window, which already contains two NSTableCellViews: HeaderCell and DataCell.
The latter consists of an icon (using NSImageView) and a label (NSTextField). Instead, I want the label and another, smaller label underneath. In IB, this looks as follows:
If I focus on just DataCell, it highlights accordingly:
Thing is, actually running the program, it looks nothing like the template:
Notice how the two NSTextFields just get smashed together into one. My understanding was that view-based NSOutlineViews (and view-based NSTableViews, for that matter) are supposed to be designed as a template from within IB. Instead, the dimensions from the template seem to get mostly ignored.
Here's the code that sets the view's values from the data source:
public class TourSourceListDelegate : NSOutlineViewDelegate
{
public override bool IsGroupItem(NSOutlineView outlineView, MonoMac.Foundation.NSObject item)
{
return (item as TourSourceListDataSource.Item).IsHeader;
}
public override NSView GetView(NSOutlineView outlineView, NSTableColumn tableColumn, MonoMac.Foundation.NSObject item)
{
if (IsGroupItem(outlineView, item))
{
return outlineView.MakeView("HeaderCell", this);
}
else
{
var data = item as TourSourceListDataSource.Item;
var dataView = outlineView.MakeView("DataCell", this);
(dataView.Subviews[0] as NSTextField).StringValue = data.Name;
(dataView.Subviews[1] as NSTextField).StringValue = data.Date_start.ToShortDateString();
return dataView;
}
}
}
I've tried overriding GetRowHeight, but that doesn't seem to resolve the problem (it makes more room, but still doesn't let the views distribute themselves properly), nor does it seem necessary.
I've also tried playing with the various Autosizing, Autoresizes Subviews, etc. toggles in IB, but that doesn't seem to produce intuitive results, and again, it doesn't seem necessary — the view as presented in IB is exactly what I want, just with slightly longer labels in practice.
I haven't tried converting this to AutoLayout yet.
What obvious step am I missing?
Some more info that probably doesn't make a difference: this is a Xamarin.Mac/MonoMac project with Xcode 5.0, MacOSX10.8.sdk, Xamarin Studio 4.0.12, Xamarin.Mac 4.0.12, and Mono 3.2.3 (targeting Mono / .NET 4.0). I've also enabled App Sandboxing.
What's important in interface builder is the view hierarchy. What kind of view is that cell? Are those labels really subviews of the cellview or not? The hierarchy should look something like:
One thing that's fishy that I see is accessing dataView.Subviews[0] and [1]. If you're adding subviews to your cells then should be creating your own NSTableViewCell subclasses, with each view connecting to the subclass' IBOutlet properties. The subclass doesn't need any code in its implementation, just the declaration of its properties in #interface, such as titleField and descriptionField, and an empty #implementation that auto-synthesizes them.
Then makeViewWithIdentifier (or apprently the glue MakeView in Xamarin) when passed the right identifier should create your NSTableViewCell subclass, and at runtime you can verify that using po dataView in the debugger. Then you access the subviews using the properties of your NSTableViewCell subclass' interface instead of assuming which view is in which position with the subview array, using dataView.titleField and dataView.descriptionField.
If your cell view has one text field then you can use NSTableViewCell without subclassing, but do connect up the textField outlet (its connected by default as long as you don't delete & recreate the cell view's label view) so you can access it through the property, again instead of having to dive into the subviews array.
All that said, it's not really clear why you're seeing what you are. It looks like those aren't the subviews you expect, and might even look like the wrong fonts as well as in the wrong positions. Using a custom subclass of NSTableViewCell and verifying its class at runtime is a good way of making sure it's creating the view you expect, but you can also dump the subview within the debugger using po [dataView _subtreeDescription].

Scroll to UITableViewCell that contains a certain UITextField

I have a UITableView with static custom UITableViewCells, I need to scroll a text field into view as currently they are getting hidden behind the keyboard after the return key is pressed and the next responder is set. I know i need to use scrollToRowAtIndexPath:atScrollPosition:animated:. How would I go about scrolling to one of the text boxes?
I know this should scroll itself but if your UIViewController derives from UITableViewController (as Apple states it should be) then the UITableViewController class handles this behaviour for you by implementing UITextFieldDelegate, UIScrollViewDelegate etc. My application stopped doing this as I changed to derive from UIViewController and add the table view on top of the view controller's UIView. So basically I'm missing the features from UITableViewController because I (for other reasons) choose to derive from UIViewControler.
I do this all the time. The way that I do it is I have a method that is called in the UIControlEventEditingDidBegin for the textfield, and in that method, I do:
-(void)startEdit:(UITextField *)textField {
self.prevOffset = self.tableView.contentOffset.y; //I like storing the current offset so I can restore it when the text stops editing, you don't have to do this.
int offSet = [textField superview].frame.origin.y; //this gets the y coordinate of the cell the textField is in. If the table is not at 0,0, you also need to add [[textField superview] superview].frame.origin.y;
offSet-=(self.view.frame.size.height-KEYBOARD_HEIGHT)/2; //where KEYBOARD_HEIGHT is 216 in portrait and 160 in landscape;
if (offSet<0) offSet = 0;
[UIView animateWithDuration:0.3 animations:^{
[self.tableView setContentOffset:CGPointMake(0,offSet)];}];
}
I do a lot of other things as well, but I believe they are specific for my application.
First, if the offset is greater than 0, I set teh contentInset to UIEdgeInsetsMake(0,0,KEYBOARD_HEIGHT,0) because I was having some jumpy scrollViews before I did that.
Also, if the original offset (self.prevOffset) plus the frame's height is greater than the content size (which would also cause jumping as it sets the offset too low then jumps back), I set the prevOffset to MAX(0,contentSize.height-frame.size.height).
These things aren't neccessary, but you are getting Scroll/TableViews that are jumping around, try them out.
UITableViewController has the delegate protocols already in the header field. Since your class is no longer a UITableViewController, you need to manually add the delegate protocol headers for a UITableView to your .h file.
When I create a custom view controller that has a UITableView, I start off with a UITableViewController too, just to get the delegate methods, but then I change UITableViewController to UIViewController as you have done, and manually add the Delegate protocols to the header.
If you want, you can look at UITableViewController.h and copy over the delegate protocols.
For your reference they are:
<UITableViewDelegate, UITableViewDataSource>
So your .h file should look similar to this:
#interface MyTableViewController : UIViewController <UITableViewDelegate, UITableViewDataSource>
Also, don't forget to set the delegates of the controller to the file's owner in Interface builder, or to self in code.
You may also find it a lot easier to use a framework such as the freely available Sensible TableView framework. These frameworks usually provide all the data entry cells out of the box, and will take care of all scrolling/resizing chores on your behalf.

Where to place the code to change the properties of a UIView

If I'm creating a UIView programmatically and I wish to change the UIView properties (background, for example, or actually, messing with CALayers), must I place the code outside of UIView such as in the View controller? Can I put the code somewhere inside UIView?
I was checking out the CoreAnimationKioskStyleMenu example, its code is inside UIView but it's loaded from Nib and can be placed at awakeFromNib, so it doesn't seem to apply to my case.
That depends. Obviously, a good way to handle this is to use a xib file, as it is designed to hold data like this, but that isn't always the best answer for every situation.
If the view is meant to be reused frequently (like a button, or some widget) throughout the application, its best to store all that customization in a subclass of the UIView.
If its a single larger view that will always be managed by a UIViewController, you can keep some of the information in the UIViewController. However, if you end up subclassing a UIView anyway it's probably best practice to keep the data in the UIView.
As a general note, I believe its worth your time to push as much of this data into a xib using interface builder. Magic values (like colors or sizes) peppered through your code will always be a problem if you want to modify it. I have found modifying a xib to be much easier.
Actually there are some methods where you could place initialization/ customization code.
(void)willMoveToSuperview:(UIView *)newSuperview;
(void)didMoveToSuperview;
will get called as soon as u add the view as a subview to another view, at which point you already have the frame and all the properties, and you can do further customizing as you wish.
(void)layoutSubviews -- generally used for changing subviews' frames and layout organization.
Will get called each time the view needs to be redrawn by the system, or when you specifically call [self setNeedsLayout] on your UIView.
Hope this helps.

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