keyDown: Not Called on NSClipView Subclass - objective-c

My app is not document based, and its sole window is managed by a custom, xib-based NSWindowController subclass that I instantiate within the app delegate code:
- (void) applicationDidFinishLaunching:(NSNotification*) aNotification
{
_mainWindowController = [MainWindowController new];
// (stored in ivar just to prevent deallocation)
//[_mainWindowController showWindow:self];
// ↕︎ Not sure about the difference between these two... both seem to work.
[[_mainWindowController window] makeKeyAndOrderFront:self];
}
I have subclassed NSClipView to "center content inside a scroll view" (instead of having it pegged to the lower left corner) when it is zoomed to a size smaller than the clip view, and also implement custom functionality on mouse drag etc.
My window does have a title bar.
My window isn't borderless (I think), so I am not subclassing NSWindow.
I have overriden -acceptsFirstResponder, -canBecomeKeyView and -becomeFirstResponder in my NSClipview subclass (all return YES).
The drag events do trigger -mouseDown: etc., and if I set a breakpoint there, the first responder at that point is the same as the window hosting my clip view: [self.window firstResponder] and [self window] give the same memory address.
What am I missing?
Update
I put together a minimal project reproducing my setup.
I discovered that if my custom view is the window's main view, -keyDown: is called without problems. But if I place a scroll view and replace its clip view by my custom view (to do that, I need to change the base class from NSView to NSClipView, of course!), -keyDown: is no longer triggered.
I assume it has something to do with how NSScrollView manages events (however, as I said before, -mouseDown:, -mouseDragged: etc. seem to be unaffected).
I also discovered that I can override -keyDown: in my window controller, and that seems to work, so I have decided to do just that (still open to an answer, though). Also, since I'm trying to detect the shift key alone (not as a modifier of another key), I'd rather use:
- (void) flagsChanged:(NSEvent *) event
{
if ([event modifierFlags] & NSShiftKeyMask) {
// Shift key is DOWN
}
else{
// Shift key is UP
}
}
...instead of -keyDown: / -keyUp: (taken from this answer).

Related

After bouncing of table to top App get crash [duplicate]

Here's how the scroll views work: One scroll view is paging enabled in the horizontal direction. Each 'page' of this scroll view contains a vertically scrolling UITableView. Without modification, this works OK, but not perfectly.
The behaviour that's not right: When the user scrolls up and down on the table view, but then wants to flick over to the next page quickly, the horizontal flick/swipe will not work initially - it will not work until the table view is stationary (even if the swipe is very clearly horizontal).
How it should work: If the swipe is clearly horizontal, I'd like the page to change even if the table view is still scrolling/bouncing, as this is what the user will expect too.
How can I change this behaviour - what's the easiest or best way?
NOTE For various reasons, a UIPageViewController as stated in some answers will not work. How can I do this with cross directional UIScrollViews (/one is a table view, but you get the idea)? I've been banging my head against a wall for hours - if you think you can do this then I'll more than happily award a bounty.
According to my understanding of the question, it is only while the tableView is scrolling we want to change the default behaviour. All the other behaviour will be the same.
SubClass UITableView. UITableViews are subClass of UIScrollViews. On the UITableView subClass implement one UIScrollView's UIGestureRecognizer's delegate method
- (BOOL)gestureRecognizer:(UIPanGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UISwipeGestureRecognizer *)otherGestureRecognizer
{
//Edit 1
//return self.isDecelerating;
//return self.isDecelerating | self.bounces; //If we want to simultaneous gesture on bounce and scrolling
//Edit 2
return self.isDecelerating || self.contentOffset.y < 0 || self.contentOffset.y > MAX(0, self.contentSize.height - self.bounds.size.height); // #Jordan edited - we don't need to always enable simultaneous gesture for bounce enabled tableViews
}
As we only want to change the default gesture behaviour while the tableView is decelerating.
Now change all 'UITableView's class to your newly created tableViewSubClass and run the project, swipe should work while tableView is scrolling. :]
But the swipe looks a little too sensitive while tableView is scrolling. Let's make the swipe a little restrictive.
SubClass UIScrollView. On the UIScrollView subclass implement another UIGestureRecognizer's delegate method gestureRecognizerShouldBegin:
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
CGPoint velocity = [(UIPanGestureRecognizer *)gestureRecognizer velocityInView:self];
if (abs(velocity.y) * 2 < abs(velocity.x)) {
return YES;
}
}
return NO;
}
We want to make the "swipe is clearly horizontal". Above code only permits gesture begin if the gesture velocity on x axis is double than on y axis. [Feel free to increase the hard coded value "2" if your like. The higher the value the swipe needs to be more horizontal.]
Now change the `UiScrollView' class (which has multiple TableViews) to your ScrollViewSubClass. Run the project. :]
I've made a project on gitHub https://github.com/rishi420/SwipeWhileScroll
Although apple doesn't like this method too much:
Important: You should not embed UIWebView or UITableView objects in UIScrollView objects. If you do so, unexpected behavior can result
because touch events for the two objects can be mixed up and wrongly
handled.
I've found a great way to accomplish this.
This is a complete solution for the problem. In order to scroll the UIScrollView while your UITableView is scrolling you'll need to disable the interaction you have it.
- (void)viewDidLoad
{
[super viewDidLoad];
_myScrollView.contentSize = CGSizeMake(2000, 0);
data = [[NSMutableArray alloc]init];
for(int i=0;i<30;i++)
{
[data addObject:[NSString stringWithFormat:#"%d",i]];
}
UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTap:)];
[self.view addGestureRecognizer:tap];
}
- (void)handleTap:(UITapGestureRecognizer *)recognizer
{
[_myTableView setContentOffset:_myTableView.contentOffset animated:NO];
}
- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = NO;
}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
scrollView.userInteractionEnabled = YES;
}
To sum up the code above, if the UITableView is scrolling, set userInteractionEnabled to NO so the UIScrollView will detect the swipe. If the UITableView is scrolling and the user taps on the screen, userInteractionEnabled will be set to YES.
Instead of using UIScrollView as a container for these multiple table views, try using a UIPageViewController.
You can even integrate this into your existing view controller setup as a child view controller (directly replacing the UIScrollView).
In addition, you'll likely want to implement the required methods from UIPageViewControllerDataSource and possibly one or more of the methods from UIPageViewControllerDelegate.
Did you try the methods : directionalLockEnabled of both your table and scroll and set them up to horizontal for one and vertical for the other ?
Edit :
1)
What you want to do is very complicate since the touch wait some time (like 0.1s) to know what your movement will be. And if your table is moving, it will take your touch immediately whatever it is (because it's suppose to be reactive movement on it).
I don't see any other solution for you but to override touch movement from scratch to detect immediately the kind of mouvement you want (like if the movement will be horizontal) but it will be more than hard to do it good.
2)
Another solution I can advise you is to make your table have left and right margin, where you can touch the parent scroll (pages thing so) and then even if your table is scrolling, if you touch here, only your paging scroll will be touched. It's simpler, but could not fit with your design maybe...
Use UIPageViewController and in the -viewDidLoad method (or any other method what best suits your needs or design) get UIPageViewController's UIScrollView subview and assign a delegate to it. Keep in mind that, its delegate property won't be nil. So optionally, you can assign it to another reference, and then assign your object, which conforms to UIScrollViewDelegate, to it. For example:
id<UIScrollViewDelegate> originalPageScrollViewDelegate = ((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]).delegate;
[((UIScrollView *)[pageViewController.view.subviews objectAtIndex:0]) setDelegate:self];
So that you can implement UIScrollViewDelegate methods with ease. And your UIPageViewController will call your delegate's -scrollViewDidScroll: method.
By the way, you may be obliged to keep original delegate, and respond to delegate methods with that object. You can see an example implementation in ViewPagerController class on my UI control project here
I faced the same thing recently. My UIScrollview was on paging mode and every page contained a UITableView and like you described it worked but not as you'd expected it to work. This is how solved it.
First I disabled the scrolling of the UIScrollview
Then I added a UISwipeGestureRecognizer to the actual UITableView for left and right swipes.
The action for those swipes were:
[scroll setContentOffset:CGPointMake(currentPointX + 320, PointY) animated:YES];
//Or
[scroll setContentOffset:CGPointMake(currentPointX - 320 , PointY) animated:YES];
This works flawlessly, the only down side is that if the user drags his finger on the UITableVIew that will be considered as a swipe. He won't be able to see half of screen A and half of screen B on the same screen.
You could subclass your scroll view and your table views, and add this gesture recognizer delegate method to each of them...
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:
(UIGestureRecognizer *)otherGestureRecognizer {
return YES;
}
I can't be sure this is exactly what you are after, but it may come close.

Show NSWindow on right click in NSTableView

I'd like to display an NSWindow when right clicking an item in an NSTableView, similarly to how the available outlets are shown in Interface Builder when you right click an object:
Unfortunately you can only use an NSMenu subclass as the menu property.
I also didn't find a delegate method of NSTableView that notifies about right clicks.
I was able to subclass NSTableView and implement rightMouseDown: and rightMouseUp: to be notified about those events, but if I set the menu property of the row cells to nil, they are not highlighted when right clicked, even though I call the super implementation):
- (void)rightMouseDown:(NSEvent *)theEvent {
[super rightMouseDown:theEvent];
NSPoint eventLocation = [theEvent locationInWindow];
eventLocation = [self convertPoint:eventLocation fromView:nil];
NSInteger rowIndex = [self rowAtPoint:eventLocation];
NSLog(#"Right clicked at row index %d", rowIndex);
}
I would like to have the highlight effect in the image below but display a window instead of the context menu:
First for the right click: explicitly select the row on right click (e.g. via this message). Then create your own NSWindow descendant, set an own NSView class as contentView and in the view you can draw the black background, rounded borders and what not. Show this window in your right click handler.
You can use an NSPopover, which works quite nicely. A popover creates a window for you, even if it is somewhat hidden. You'll get it from your controls if you send them the window message, and can register to listen for events, for instance.
The whole popover can be created in IB, and just have to implement the showRelativeToRect:ofView:preferredEdge: method in code.
To catch the right click event, you can use rightMouseDown:, which is originally defined in NSResponder, but is overridden in NSView to simply catch the event and show menu and it doesn't pass the event upwards in the responder chain (or the inheritance chain, for that matter). Hence, you simply implement that method to call showRelativeToRect:ofView:preferredEdge:.
You will typically need to have the contents in an NSViewController and its own accompanying nib file.
The NSPopover's contentViewController property can be set in IB, too.
All in all, not much code needed.
This tutorial is useful.

Control+Click not triggering menuForEvent

All,
So I have a subclass of NSBox and have subviews in it like a label and two imageViews. I have overridden menuForEvent: in it. However, when I click on the NSBox to select it and then later Control+Click on any of its subviews then menuForEvent: is never called.
I don't understand why that is the case.
There is a difference in how control-clicks and right-clicks are handled by NSView (as jfewtr pointed out). Contextual menus will appear for a right-click if the click falls within a subview, but not for a control-click.
I was surprised by this and actually wrote a post about it with more details here: NSView control-click quirks
There are a couple potential solutions, but overriding/customizing your entire subview tree is probably not the best choice. I've found the best fix for this is to display your contextual menu explicitly in your top-level view (your NSBox subclass) for a control-click:
- (void)mouseDown:(NSEvent *)theEvent
{
if (theEvent.modifierFlags & NSControlKeyMask)
{
[NSMenu popUpContextMenu:[self menuForEvent:theEvent] withEvent:theEvent forView:self];
}
}
While it's not great to hardcode this behavior, it avoids manipulating or traversing your entire subview tree, which can incur more problematic side effects/bugs.
You need to implement menuForEvent: in the subviews too, and forward the event to your superview's (NSBox subclass) implementation of menuForEvent:
- (NSMenu *)menuForEvent:(NSEvent *)event
{
return [[self superview] menuForEvent:event];
}
I assumed that it would automatically fall through to the superview without the need for subclassing the subviews. I found that a right-click does, but, for some reason, a control-click does not.

NSView's context NSMenu is never shown even though all the right methods are being called

I have an NSCollectionView with a bunch of NSViews in it, stacked vertically, to make it look a bit like UIKit's UITableView. Everything works as expected, except for one thing:
When right-clicking any one of the NSViews, I expect the NSMenu I set to be view's menu to be shown, but alas - nothing happens.
The crazy part is all the right methods are being called, exactly as could be expected: -rightMouseDown:, -menuForEvent: and finally -menu.
When I set up any object as the NSMenu's delegate, menuWillOpen: is not called, so it seems to me something fails over on Apple's side of things, just in between asking for the menu, and actually showing it.
Would anyone be able to shed a light on this?
Thanks in advance.
PS. For what it's worth, NSMenus I present manually (without relying on Apple's right-click handling) using popUpMenuPositioningItem:atLocation:inView: are shown.
Edit / Update / Clarification
The NSCollectionView in question is inside an NSWindow that's being shown when an NSStatusItem is clicked, like CoverSutra/TicToc/what have you. Some code from the MyWindow NSWindow subclass:
- (void)awakeFromNib {
[self setStyleMask:NSBorderlessWindowMask];
[self setExcludedFromWindowsMenu:YES];
}
- (BOOL)canBecomeMainWindow {
return YES;
}
- (BOOL)canBecomeKeyWindow {
return YES;
}
- (BOOL)isMovable {
return NO;
}
- (void)presentFromPoint:(NSPoint)point {
point.y -= self.frame.size.height;
point.x -= self.frame.size.width / 2;
[self setFrameOrigin:point];
[self makeMainWindow];
[self makeKeyAndOrderFront:self];
}
presentFromPoint: is the method I use to present it from any point I like, in my case from just below the NSStatusItem. (Not really relevant to this problem)
My application has LSUIElement in its Info.plist set to YES by the way, so it doesn't show a menu bar or a Dock icon. It lives in the status bar, and has a window that's shown when the NSStatusItem is clicked.
The view hierarchy is as follows:
MyWindow => contentView => NSScrollView => NSCollectionView
The NSCollectionView has an NSCollectionViewItem subclass connected to its itemPrototype property, and the NSCollectionViewItem subclass has an NSView subclass connected to its view property.
The NSView subclass, in turn, has an NSMenu connected to its menu property.
And last but not least: This NSMenu has one NSMenuItem sitting inside it.
Both the NSCollectionViewItem subclass and the NSView subclass do nothing interesting as of now, they're just empty subclasses.
The NSMenu connected to the NSView's menu property is what should be shown when the NSView is right-clicked, but as I hope I have made clear: It isn't actually shown.
Update
I still have no idea what caused this problem, but I've decided to 'move on' from NSCollectionView, as it wasn't really fit for what I was trying to do anyway, and I am now using TDListView which works like a charm.

UISplitViewController non root, forcing custom rotation methods, makes master view dissappear

I'm trying to add a split view inside of a tab bar, and since the split view isn't the root, it doesn't properly get the rotation notifications, so the delegate's methods are never called to add the button to the toolbar in the detail view.
I've rigged it up so I can generate the popover when rotated, but when this method is called, the view dissappears from the landscape mode, and if you activate it and then rotate back into landscape, it's a black empty box where the master view used to be. How do I get rid of this occuring?
-(void) displayPopover:(id)sender
{
//Toggle the popover: if it's showing, hide it
if (popoverController != nil && [popoverController isPopoverVisible])
{
[popoverController dismissPopoverAnimated:NO];
}
else
{
//Create a Popover displaying the master view
if (popoverController == nil)
{
popoverController=[[UIPopoverController alloc] initWithContentViewController:self->rootController];
popoverController.popoverContentSize=CGSizeMake(300, 500);
}
[popoverController presentPopoverFromBarButtonItem:[detailController.toolbar.items objectAtIndex:0] permittedArrowDirections:UIPopoverArrowDirectionAny animated:NO];
}
You will need to remove all the objects from window using:
[appdelegate window ] subviews] objectAtIndex:0] removeFromSuperview];
Then add your splitview to the window, you can get the view callbacks.
I would recommend either finding a way to get your SplitViewController to be root, or creating a custom subclass of the UISplitViewController that allows for non-root placement.
I really like what Matt Gemmell did here: http://mattgemmell.com/2010/07/31/mgsplitviewcontroller-for-ipad
Using a custom subclass like Matt's will allow you to benefit from all the same delegate methods that a SplitView as root would allow. I used it in a project where I wanted my SplitView to appear as a modal - almost impossible with a traditional UISplitViewController.
so your split view has rotation enabled (shouldAutorotateToInterfaceOrientation:) now you have to make sure that the tab controller has also rotation enabled (should be the appDelegate, am I right?) AND you have to make sure that every other view that is in your TabBar has also rotation enabled!
so if your TabBar contains 2 tabs you have to set the rotation in 3 classes.