Is there a way to select a segue anchor programmatically? - objective-c

Suppose I have a Storyboard containing a view that contains a button. When the user presses this button, a popover comes up.
Thus, I need to set an anchor by dragging the segue to the button using Xcode (and then do performSegueWithIdentifier:).
So, my question is: is there a way to set this "anchor" programmatically?
Thank you.

In my case I've added programmatically several UIBarButtonItem.
The problem of only using an invisible view as an archor is that, if like in my case, the size of the UIBarButtonItem is changing it's size, the arrow of the popover doesnt appear centered, and althought it works, looks a bit strange.
How to solve it.
Create a small view in storyboard ( the size doesnt really matter ), make it invisible, and link it.
In my case this is called invisibleViewAsArchor
Connect the UIBarbutton item with the follow action.
-(IBAction) showMyPopover:(id)sender {
if([self.popoverController isPopoverVisible])
{
[self.popoverController dismissPopoverAnimated:YES];
}else{
self.invisibleViewAsArchor.frame = CGRectMake([sender view].frame.origin.x,
[sender view].frame.origin.y-50,
[sender view].frame.size.width,
[sender view].frame.size.height);
[self performSegueWithIdentifier:#"segue_to_something" sender:self];
}
}
as you can see before it shows the popover (with performSegueWithIdentifier), I'm changing the frame
of the Archor with the values from the button that has fired the event.
Hope it helps.

In the storyboard anchor the popover to some arbitrary button. Don't worry too much about which one as it will get overridden in the code.
In the view controller method prepareForSegue, add the code:
let dest = segue.destinationViewController
dest.popoverPresentationController?.barButtonItem = <your bar button here>
or if you want to anchor to a view instead
dest.popoverPresentationController?.barButtonItem = nil
dest.popoverPresentationController?.sourceView = <your view here>

You can't programmatically create segue's as explained here: Creating a segue programmatically, however, you can configure which destination controller you want to display at run-time. This is explained in the apple documentation here: Configuring the Destination Controller When a Segue is Triggered.
Hopefully this helps!

I had the same problem where I was creating a BarButtonItem programmatically. You may also be able to get around it by creating an invisible, disabled button which you can set as the anchor in IB.

Related

Can't rename or set new backBarButtonItem in UINavigationBar

I am using the XCode 4.3.2 and only want to set the text of my back button in my UINavigationBar.
Theh simple way is use
- (void)loadView {
[super loadView];
self.navigationItem.backBarButtonItem =
[[UIBarButtonItem alloc] initWithTitle:#"Back"
style: UIBarButtonItemStyleBordered
target:nil
action:nil];
}
But id don't work. I open my Storyboard and see this:
The back button is disable. So, I can't set the button or disable it. What can I do now?
The backBarButton is used to set what the back button will say on your next view controller that you push, i.e. what the back button will say to let the user know how to get back to the current view controller. It's not used to control what the back button says on the current view controller. That's a common source of confusion.
In terms of what appears in IB, I'm not at all sure about what you're doing there. If you have a navigation bar, and you're pushing view controllers as the user goes through the app, there's nothing you need to do in IB (other than making sure you've got your navigation controller set up in your initial view). But there's no need to set up the back button in IB.
If you're trying to do something else, let us know, but that's the standard flow.

Adding a Navigation Controller to a View based Application adds top margin

I am trying to programmatically add a Navigation Controller to my View based Application. This is the code I am using (this code gets called after a button press in a view controller):
MainMenu *control = [[MainMenu alloc] initWithNibName: #"MainMenu" bundle: nil];
UINavigationController *navControl = [[UINavigationController alloc] initWithRootViewController: control];
[self.view addSubview:navControl.view];
[control release];
That works, but this ends up happening:
Notice the odd margin above the Navigation control.... My View controller that I am adding the Navigation Controller to has a gray background which you can see.
Any ideas??
If you have a better way of adding a Navigation Controller to a View based Application I am very open to suggestions!
Thank you in advance!
Thank you both for your response, but unfortunately, wantsFullScreenLayout set to YES or NO in the code didn't have any effect. I was able to push the Navigation Controller up by 20 using this line of code:
self.navigationController.navigationBar.frame = CGRectOffset(self.navigationController.navigationBar.frame, 0.0, -20.0);
but then what happened was that the View Controller did not move up with the Navigation bar and left a gap below the Navigation Bar and the View Controller. What eventually worked was checking the Wants Full Screen checkbox in IB in the MainWindow view controller that is automatically generated when you set up a view based application.
The gap you are seeing is the same height as a status bar. Check the status bar settings in your NIB file.
Chances are you want to make the UINavigationController the root view controller for the window, rather than whichever view controller you have now. That would be the better way to do it.
The reason you're seeing that extra margin at the top is because UINavigationController normally expects that it will be sized to fill the entire screen (except perhaps a tab bar at the bottom, if it's inside a UITabBarController), and therefore expects that the top edge of its view will be under the status bar if the status bar is visible. Therefore, it places its navigation bar 20 pixels below the top of its view to leave space for the status bar, without bothering to check whether its view actually is under the status bar. Interestingly, sometimes a re-layout operation will perform this check, but that's unreliable. What I've found works well in a situation like this is to set the UINavigationController's wantsFullScreenLayout property to NO. Then ti doesn't try to leave room for the status bar, so everything works as expected.
I've been struggling with this same issue this morning. Since setting the wantsFullScreenLayout property doesn't seem to have any effect, I resorted to using a little subclass, which worked fine:
#interface MyNavigationController : UINavigationController
#end
#implementation MyNavigationController
- (BOOL)wantsFullScreenLayout;
{
return NO;
}
#end
Its so simple to remove that gap..
self.navigationBar.view.frame = CGRectMake(0, -20, 320, 480);

How to make a custom tableView cell accessory

I have not yet found any really good examples on how to do this. There is an image that I want to use as the accessory button and when I put it in and click on it doesn't work. So it looks correct but doesn't work...
Here is my code:
[cell setAccessoryType:UITableViewCellAccessoryDetailDisclosureButton];
cell.accessoryView = [[UIImageView alloc]
initWithImage:[UIImage imageNamed:#"TableView_Green_Disclosure.png"]];
So how do I get my UIImageView to call accessoryButtonTappedForRowWithIndexPath whenever it is tapped?
A thorough reading of accessoryView and accessoryType would reveal that they are mutually exclusive ways to customize a cell.
Setting the accessoryType will cause the table view delegate method to be called when it is tapped.
Setting the accessoryView will ignore the setting of accessoryType and give you something to display. If you want to receive a callback from the custom view you've put in place, it should be a control that is wired up to do so. (Or any view with a gesture recognizer.)
If you use a button, and set its action to accessoryTapped:, you will receive the button as the "sender" argument. You can walk up the view hierarchy until you find a table view cell, and then ask your table view what the indexPath of that cell is. This will then get you an index into your model objects and you be able to act on it appropriately.
Alternate to the button, you can enable interaction on the UIImageView above, and add a gesture recognizer to it.
To make the button actually do something, you'll need to implement - (void)tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath from UITableViewDelegate.
When an accessory button is tapped in a row, this method will be called and you'll have the chance to act appropriately using the passed in index path to determine which row's accessory was tapped.
Check the blog post hdr->cmdline for creating custom accessory view for UITableView.
The author used UIButton objects with images for custom accessory view.
To make use of the accessoryView - you would need to set the cell's accessoryType to UITableViewCellAccessoryNone deposit a UIButton (with associated image) into the cell and then wire it up to receive user touches. You might use something like the code below as the IBAction response to the cell's UIButton being touched:
- (IBAction) accessoryButtonPressed:(id) sender
{
NSUInteger pathInts[] = { 0,0 };
pathInts[1] = self.currentselectedrow; // ivar set when tableview row last selected
NSIndexPath* indexPath = [NSIndexPath indexPathWithIndexes:pathInts length:2];
[self tableView:mytableview accessoryButtonTappedForRowWithIndexPath:indexPath];
}
The UIButton would be wired to execute this glue code by way of a line inside your tableview's "cellForRowAtIndexPath:" function
[thecell setButtonTarget:self action:#selector(accessoryButtonPressed:)];
One thing I noticed is that the UIButton seems to want a 'swipe right' versus a simple 'tap' touch in order to trigger the event - but it could be my beta iOS that's the problem. Note that I had added a UIButton* object named 'cell_accessoryButton' to the Custom Cell source.
In the cell's source you'd support the 'setButtonTarget' call with code like this:
- (void) setButtonTarget:(MyViewController*)inTarget action:(SEL) inAction
{
[self.cell_accessoryButton addTarget: inTarget
action: (SEL) inAction
forControlEvents: UIControlEventTouchUpInside];
}
It's so much easier to just use the accessoryType reference and let iOS do the heavy lifting - but, if you want a custom graphic, etc - this is another path that works.

How do I add a navigation bar's Done button to a popover's passthroughViews?

I'm working in an iPad app that has a split view with a navigation controller in the detail view. The deepest view that can be in the navigation stack is an edit view where the user can edit data. I put an edit button as the rightBarButtonItem and when editing starts, change it to a done button.
When editing commences and the user touches on a particular field, I present a popoverview with a list of possible choices filtered by what they are typing - a form of autofill based on all the values of that field in all other objects.
This works fine, except if you try touching on the done button. The popover eats this touch and dismisses itself. So the user has to touch done again.
I tried using the uipopovercontroller's passthroughViews property, but UIBarButtonItem is not a view and there is no documented way to get the view for the done button or even the navigation bar. I can access the variable in gdb, but it isn't accessible via KVC.
Any ideas on how I can prevent the need to tap done twice?
I've thought about a gesture recognizer on the window, but that seems messy and I'd have to handle rotation.
In case anyone gets here from google, copypaste from other question:
The only solution I found for now is to create UIBarButtonItem with custom UIButton using
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
//code for styling button
UIBarButtonItem *b = [[[UIBarButtonItem alloc]
initWithCustomView:button]
autorelease]
and then
popoverController.passthroughViews = [NSArray arrayWithObject:b.customView];
But be prepared - you cannot create UIButton that looks like UIBarButtoItem. I ended up with creating image that reassembled UIBarButtonItem.

Why is it that my UITableViewController setEditing:animated: method is not called?

I must be doing stupid, but I can't see what: my UITableViewController subclass is never called when the edit button of my navigation is pressed.
What could be causing that?
My view hierarchy is loaded from a Nib file and put inside a popover. The [+] button is connected to the insertNewObject action of my UITableViewController subclass. It works fine.
The [Edit] button however has no action to connect to. The doc says it will automatically call the setEditing:animated: method of the view controller, which I override.
The nib file is set up pretty much as usual AFAICT. And in fact, I'm not sure what additional detail I can give that would suggest my mistake.
What is the control flow from the click on the [Edit] button to the call of the setEditing:animated method?
I feel like we must be missing the same thing.
Whatever the case, I made it work by doing the following.
IBOutlet UIBarButtonItem *editButton;
-(IBAction)editButtonPressed:(id)sender {
[self setEditing:YES animated:YES];
}
- (void)setEditing:(BOOL)editing animated:(BOOL)animate
{
if(self.tableView.isEditing)
{
self.editButton.style = UIBarButtonItemStylePlain;
self.editButton.title = #"Edit";
}
else
{
//self.editButton.style = UIBarButtonSystemItemDone;
self.editButton.style = UIBarButtonSystemItemEdit;
self.editButton.title = #"Done";
}
// Toggle table view state
[super setEditing:!self.tableView.isEditing animated:animate];
}
I hooked the editButton up to the button I added to the nav bar and it's action to the editButtonPressed IBAction. After doing that my setEditing: is called (obviously) and the super call toggles the table view's editing state.
I'd like to use the system defined button styles, but the appropriate one is commented out because while it did change style I couldn't figure out how to change the text from "Edit" to "Done" so I had to do it all manually (that only worked if I left the button as Custom and set the style generically). This has the downside of not being localized (for free), etc.