Question

I’m trying to re-write an application I have for Windows in Objective-C for my Mac, and I want to be able to do something like Mac’s hot corners. If I move my mouse to the left side of the screen it will make a window visible, if I move it outside of the window location the window will hide again. (window would be pushed up to the left side of screen).

Does anyone know where I can find some demo code (or reference) on how to do this, or at least how to tell where the mouse is at, even if the current application is not on top. (not sure how to word this, too used to Windows world).

Thank you

-Brad

Answer 1

Here’s what I came up with. Thanks to Peter for the above tips.

   @interface SlidingWindow : NSWindow
    {
        CGRectEdge _slidingEdge;
        NSView *_wrapperView;
    }


    @property (nonatomic, assign) CGRectEdge slidingEdge;
    @property (nonatomic, retain) NSView *wrapperView;

    -(id)initWithContentRect:(NSRect) contentRect 
                   styleMask:(unsigned int) styleMask 
                     backing:(NSBackingStoreType) backingType 
                       defer:(BOOL) flag;

    - (NSView*)wrapperViewWithFrame:(NSRect)bounds;

    - (BOOL)mayOrderOut;

    @end

    @interface SlidingWindow ()

    - (void)adjustWrapperView;

    - (void)setWindowWidth:(NSNumber*)width;
    - (void)setWindowHeight:(NSNumber*)height;

    @end


    @implementation SlidingWindow


@synthesize slidingEdge = _slidingEdge;
@synthesize wrapperView = _wrapperView;


- (id)initWithContentRect:(NSRect) contentRect 
                styleMask:(unsigned int) styleMask 
                  backing:(NSBackingStoreType) backingType 
                    defer:(BOOL) flag
{

    if ((self = [super initWithContentRect:contentRect
                                 styleMask:NSBorderlessWindowMask 
                                   backing:backingType
                                     defer:flag])) {
        /* May want to setup some other options, 
         like transparent background or something */

        [self setSlidingEdge:CGRectMaxYEdge];
        [self setHidesOnDeactivate:YES];
        [self setCollectionBehavior:NSWindowCollectionBehaviorCanJoinAllSpaces];
    }

    return self;
}

- (NSView*)wrapperViewWithFrame:(NSRect)bounds
{
    return [[[NSView alloc] initWithFrame:bounds] autorelease];
}

- (void)adjustWrapperView
{
    if (self.wrapperView == nil) {
        NSRect frame = [self frame];
        NSRect bounds = NSMakeRect(0, 0, frame.size.width, frame.size.height);
        NSView *wrapperView = [self wrapperViewWithFrame:bounds];
        NSArray *subviews =  [[[[self contentView] subviews] copy] autorelease];

        for (NSView *view in subviews) {
            [wrapperView addSubview:view];
        }

        [wrapperView setAutoresizingMask:(NSViewWidthSizable | NSViewHeightSizable)];
        [[self contentView] addSubview:wrapperView];

        self.wrapperView = wrapperView;
    }

    switch (self.slidingEdge) {
        case CGRectMaxXEdge:
            [self.wrapperView setAutoresizingMask:(NSViewHeightSizable | NSViewMaxXMargin)];
            break;

        case CGRectMaxYEdge:
            [self.wrapperView setAutoresizingMask:(NSViewWidthSizable | NSViewMaxYMargin)];
            break;

        case CGRectMinXEdge:
            [self.wrapperView setAutoresizingMask:(NSViewHeightSizable | NSViewMinXMargin)];
            break;

        case CGRectMinYEdge:
        default:
            [self.wrapperView setAutoresizingMask:(NSViewWidthSizable | NSViewMinYMargin)];
    }
}

- (void)makeKeyAndOrderFront:(id)sender
{
    [self adjustWrapperView];

    if ([self isVisible]) {
        [super makeKeyAndOrderFront:sender];
    }
    else {
        NSRect screenRect = [[NSScreen menubarScreen] visibleFrame];
        NSRect windowRect = [self frame];

        CGFloat x;
        CGFloat y;
        NSRect startWindowRect;
        NSRect endWindowRect;

        switch (self.slidingEdge) {
            case CGRectMinXEdge:
                x = 0;
                y = (screenRect.size.height - windowRect.size.height) / 2 + screenRect.origin.y;
                startWindowRect = NSMakeRect(x - windowRect.size.width, y, 0, windowRect.size.height);
                break;

            case CGRectMinYEdge:
                x = (screenRect.size.width - windowRect.size.width) / 2 + screenRect.origin.x;
                y = 0;
                startWindowRect = NSMakeRect(x, y - windowRect.size.height, windowRect.size.width, 0);
                break;

            case CGRectMaxXEdge:
                x = screenRect.size.width - windowRect.size.width + screenRect.origin.x;
                y = (screenRect.size.height - windowRect.size.height) / 2 + screenRect.origin.y;
                startWindowRect = NSMakeRect(x + windowRect.size.width, y, 0, windowRect.size.height);
                break;

            case CGRectMaxYEdge:
            default:
                x = (screenRect.size.width - windowRect.size.width) / 2 + screenRect.origin.x;
                y = screenRect.size.height - windowRect.size.height + screenRect.origin.y;
                startWindowRect = NSMakeRect(x, y + windowRect.size.height, windowRect.size.width, 0);
        }

        endWindowRect = NSMakeRect(x, y, windowRect.size.width, windowRect.size.height);

        [self setFrame:startWindowRect display:NO animate:NO];

        [super makeKeyAndOrderFront:sender];

        [self setFrame:endWindowRect display:YES animate:YES];

        [self performSelector:@selector(makeResizable)
                   withObject:nil
                   afterDelay:1];
    }
}

- (void)makeResizable
{
    NSView *wrapperView = self.wrapperView;
    NSRect frame = [self frame];
    NSRect bounds = NSMakeRect(0, 0, frame.size.width, frame.size.height);

    [wrapperView setFrame:bounds];
    [wrapperView setAutoresizingMask:(NSViewWidthSizable | NSViewHeightSizable)];
}

- (void)orderOut:(id)sender
{
    [self adjustWrapperView];

    NSRect startWindowRect = [self frame];
    NSRect endWindowRect;

    switch (self.slidingEdge) {
        case CGRectMinXEdge:
            endWindowRect = NSMakeRect(startWindowRect.origin.x, 
                                       startWindowRect.origin.y,
                                       0,
                                       startWindowRect.size.height);
            break;

        case CGRectMinYEdge:
            endWindowRect = NSMakeRect(startWindowRect.origin.x, 
                                       startWindowRect.origin.y, 
                                       startWindowRect.size.width, 
                                       0);
            break;

        case CGRectMaxXEdge:
            endWindowRect = NSMakeRect(startWindowRect.origin.x + startWindowRect.size.width, 
                                       startWindowRect.origin.y,
                                       0,
                                       startWindowRect.size.height);
            break;

        case CGRectMaxYEdge:
        default:
            endWindowRect = NSMakeRect(startWindowRect.origin.x, 
                                       startWindowRect.origin.y + startWindowRect.size.height, 
                                       startWindowRect.size.width, 
                                       0);
    }

    [self setFrame:endWindowRect display:YES animate:YES];

    switch (self.slidingEdge) {
        case CGRectMaxXEdge:
        case CGRectMinXEdge:
            if (startWindowRect.size.width > 0) {
                [self performSelector:@selector(setWindowWidth:)
                           withObject:[NSNumber numberWithDouble:startWindowRect.size.width]
                           afterDelay:0];
            }
            break;

        case CGRectMaxYEdge:
        case CGRectMinYEdge:
        default:
            if (startWindowRect.size.height > 0) {
                [self performSelector:@selector(setWindowHeight:)
                           withObject:[NSNumber numberWithDouble:startWindowRect.size.height]
                           afterDelay:0];
            }
    }

    [super orderOut:sender];
}

- (void)setWindowWidth:(NSNumber*)width
{
    NSRect startWindowRect = [self frame];
    NSRect endWindowRect = NSMakeRect(startWindowRect.origin.x, 
                                      startWindowRect.origin.y, 
                                      [width doubleValue],
                                      startWindowRect.size.height);

    [self setFrame:endWindowRect display:NO animate:NO];    
}

- (void)setWindowHeight:(NSNumber*)height
{
    NSRect startWindowRect = [self frame];
    NSRect endWindowRect = NSMakeRect(startWindowRect.origin.x, 
                                      startWindowRect.origin.y, 
                                      startWindowRect.size.width, 
                                      [height doubleValue]);

    [self setFrame:endWindowRect display:NO animate:NO];    
}

- (void)resignKeyWindow
{
    [self orderOut:self];

    [super resignKeyWindow];
}

- (BOOL)canBecomeKeyWindow
{
    return YES;
}

- (void)performClose:(id)sender
{
    [self close];
}

- (void)dealloc
{
    [_wrapperView release], _wrapperView = nil;

    [super dealloc];
}

@end


@implementation NSScreen (MenubarScreen)

+ (NSScreen*)menubarScreen
{
    NSArray *screens = [self screens];

    if ([screens count] > 0) {
        return [screens objectAtIndex:0];
    }

    return nil;
}
@end