Cocoa objective-c, is there an equivalent to PHP sessions? - cocoa

My app lets the user create multiple custom views by clicking a button (the views are simple circles). When they mouseDown on the circle I send a message to the NotificationCenter and run Core Animation to make the view pulse (fade in and out). I also set NSView *activeView to the view passed to the NotificationCenter.
In the background of these user created views is a custom view named gameMap. If a user clicks outside of one of the circles then gameMap sends a message to the NotificationCenter.
What should happen here is the activeView (circle) should move to the mouse click point. But because the NotificationCenter is in my AppController class, if it is being notified of a click outside of a circle view it doesn't have an activeView to reference.
I need a way to store, independent of classes, the activeView. In PHP I would just use a $_SESSION['activeView'] = $thisView, or something similar. Can I do something like this in cocoa?

Related

How to drag a View Controller on top of a View Controller?

I have a View Controller that is presented when you first open the app, and I have another controller that can be shown on screen if you tap a button at the top of the screen. However, instead of doing it this way I was wondering if I can either drag the view down or tap the button and have an animation take care of that.
I have tried doing this with a PageView Controller, but this doesn't show the effect I wanted as it simply translates over to the next view and doesn't actually keep the initial view fixed in place while the second view slides over it.
Also, instead of a view controller would a view initially placed out of bounds in the main View Controller work? Thanks in advance!
You could use a side menu like MMDrawerController that has 4 type of animations for presenting the viewController.
Or you can create your custom UIView (not viewController) even using Interface Builder and animate that screen yourself. The animation can be started using UIScreenEdgePanGestureRecognizer.

OS X gesture and the responder chain

I have a window with a content view that does several things, including managing an iOS like navigation controller.
The window's content view front most view is an invisible custom view set here to manage drag n drop all over the window, called DragNDropView.
Now I want to manage the swipe gesture to navigate (left swipe only) in the navigation controller.
Unfortunately the DragNDropView catches the gesture (if I implement -(void)swipeWithEvent: and set acceptTouchEvents:YES on it), and I don't want that since I want the views behind it to catch it, so of course I set acceptTouchEvents to NO on the DragNDropView.
I'm suprised the gesture event does not "go down" the view hierarchy as the views below do have their acceptTouchEvents set to YES when the front most view has acceptTouchEvents set to NO.
If the front most view does not handle the gesture, the gesture event is not passed to the views behind it????
gestures handling seems to be in NSResponder, so I even expect my NSViewController subclass to handle it, but it seems I can't.
Can any one help me understanding the problem?

How to create a window in smalltalk

I am trying to make a window show up, but i keep getting a message not understood error.
The snippet:
Window new
label: 'Hello';
open
You can use this:
ScheduledWindow new
label: 'Hello';
open
Or to open larger:
ScheduledWindow new
label: 'Hello';
openIn: (20#20 extent: 300#300)
I suspect, however, that this isn't what you really want to do since it's hard to work with a window that's built this way. Can you explain more about what you want to do?
Ok, for a game like that you want to use a custom control. You start by creating a subclass of View for your game and override the displayOn: method to display the view. You can add the view to the UIPainter canvas using a ViewHolder. Set the View: property to be the name of a method that returns your custom view.
To intercept mouse clicks, you'll need to have a custom controller for your view. You'll subclass Controller or one of its subclasses to create the Controller. A method called defaultControllerClass in the View returns the name of the controller class. In the controller, you can intercept mouse events.
I suggest that you load an example game to get you started. Open the Parcel Manager, and select Toys from the list. You should see SpiderSolitaire there. This is a game written for VisualWorks that displays a custom view, does some simple animation on that view, and intercepts mouse events. That should serve as a good example to use.

Update NSView in function of events

I have a main view (subclass of NSView) and as i'm new to cocoa, i'd like to know how to update the view in function of events.
I know there are many methods that take events such as -(void)mouseMoved:(NSEvent*)event or - (void)mouseClicked:(NSEvent*)event My algorithm to determine what to do is ready. I want to know where I should update the main view: is it in the -(void)mouseMoved:(NSEvent*)event or in the - (void)drawRect:(NSRect)dirtyRect. And if it is in drawRect, then how should i pass the information to it?
Thanks in advance!
Here's a quick explanation that will hopefully get you on your way:
Handle events
User actions are communicated to your views and windows by events (keyboard + mouse) and actions (events interpreted by buttons and other controls). Your views should react to these events and actions by updating the model, which are the lower-level data structures that represent whatever your program displays to the user. If Cocoa, the view typically communicates through a controller object to make changes to the model.
Invalidate display / trigger redraw
After you have updated your model, you need to inform the view that it needs to redraw. This can be done in several ways, but the simplest way to do it is -setNeedsDisplay:YES. This will ensure that at some point in the immediate future, your view will redraw itself to display the updated model data.
Draw
At some point Cocoa will call -drawRect: on your view. Inside -drawRect:, you should read the requisite data from your model and draw the necessary graphics. You shouldn't do any manipulation of the model in this method.

Launch window from NSView subclass in cocoa

Is it possible to launch a window in an NSView subclass by clicking a NSRect? I have tried makeKeyAndOrderFront but this doesn't work.
You can't click on a rectangle. A rectangle is just four numbers.
You can have an NSView that responds to clicks, but you should consider using NSButton instead. If you really want a custom view, you can both create the button and add it as a subview of your view programmatically. Then, set the button's target to yourself and its action to the selector of a message you'll respond to by opening the window.
One more thing: You don't launch a window. Windows aren't applications and applications aren't windows. On Mac OS X, applications have windows—always more than one (counting at least the About panel). So, you'll load the window from a nib, then make it key (respond to events) and order it front.
On that point: You probably should not have your view owning a window. Consider making a controller object to own the window instead, and having your view simply forward the message to the controller object (or even hook the button up to the controller directly).

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