UIView+Tooltips.m (Broadcasts)

UIView+Tooltips.m

//
//  UIView+Tooltips.m
//  Crossword
//
//  Created by Steven Troughton-Smith on 13/09/2019.
//  Copyright © 2019 Steven Troughton-Smith. All rights reserved.
//

#import "UIView+Tooltips.h"
#import <objc/runtime.h>

/*
 WARNING:
	USE_APPKIT_TOOLTIPS enables the use of private AppKit API. This may break in the future
 */
#define USE_APPKIT_TOOLTIPS (TARGET_OS_MACCATALYST)
#define SIMULATE_TOOLTIPS_ON_LONGPRESS 0

#if USE_APPKIT_TOOLTIPS
@interface NSObject (AppKitToolTipManager)

+(id)sharedToolTipManager;
-(void)_displayTemporaryToolTipForView:(id)nsView withString:(NSString *)string;
- (id)nsWindow;
-(id)contentView;
-(void)orderOutToolTipsImmediately:(BOOL)b;
@end
#endif

#if !TARGET_OS_TV
@implementation UITooltipView

+ (instancetype)sharedInstance
{
	static UITooltipView *sharedInstance = nil;
	static dispatch_once_t onceToken; // onceToken = 0
	dispatch_once(&onceToken, ^{
		sharedInstance = [[UITooltipView alloc] init];
	});
	
	return sharedInstance;
}

- (instancetype)init
{
	self = [super init];
	if (self) {
		UIBlurEffect *blurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleSystemMaterial];
		UIVisualEffectView *blurView = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
		
		blurView.bounds = self.bounds;
		blurView.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
		
		[self addSubview:blurView];
		
		self.tooltipLabel = [[UILabel alloc] init];
		
		self.tooltipLabel.text = @"";
		self.tooltipLabel.font = [UIFont systemFontOfSize:14];
		self.tooltipLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
		self.tooltipLabel.lineBreakMode = NSLineBreakByClipping;
		
		[[blurView contentView] addSubview:self.tooltipLabel];
		
		self.layer.borderWidth = 1.0/[UIScreen mainScreen].scale;
		self.layer.borderColor = [UIColor secondarySystemFillColor].CGColor;
		
		self.layer.shadowColor = [UIColor blackColor].CGColor;
		self.layer.shadowRadius = 6;
		self.layer.shadowOffset = CGSizeMake(0, 0);
		self.layer.shadowOpacity = 0.3;
	}
	return self;
}

-(void)_sizeToFit
{
	[self.tooltipLabel sizeToFit];
	
	self.frame = CGRectInset(self.tooltipLabel.bounds, -5, -3);
	
	self.tooltipLabel.frame = CGRectInset(self.bounds, 5, 3);
}

-(CGRect)displayRectForViewRect:(CGRect)convertedRect
{
	CGRect labelRect = self.bounds;
	
	return CGRectMake(convertedRect.origin.x+convertedRect.size.width/2-labelRect.size.width/2, convertedRect.origin.y+convertedRect.size.height, self.frame.size.width, self.frame.size.height);
}

-(void)showFromRect:(CGRect)convertedRect
{
	
#if USE_APPKIT_TOOLTIPS
	id nsWindow = [self.window nsWindow];
	
	if (NSClassFromString(@"NSToolTipManager") && [NSClassFromString(@"NSToolTipManager") respondsToSelector:@selector(sharedToolTipManager)])
	{
		id manager = [NSClassFromString(@"NSToolTipManager") sharedToolTipManager];
		
		if (manager && [manager respondsToSelector:@selector(_displayTemporaryToolTipForView:withString:)])
		{
			[manager _displayTemporaryToolTipForView:[nsWindow contentView]  withString:self.tooltipLabel.text];
		}
	}
	self.visible = YES;
#else
	[CATransaction setDisableActions:YES];
	[self _sizeToFit];
	
	CGRect labelRect = self.bounds;
	self.alpha = 0;
	CGRect safeRect = CGRectMake(convertedRect.origin.x+convertedRect.size.width/2-labelRect.size.width/2, convertedRect.origin.y+convertedRect.size.height, self.frame.size.width, self.frame.size.height);
	
	CGFloat edgePadding = 8;
	
	if (safeRect.origin.x+safeRect.size.width > self.window.bounds.size.width)
		safeRect.origin.x = self.window.bounds.size.width - edgePadding - safeRect.size.width;
	
	if (safeRect.origin.x < 0)
		safeRect.origin.x = edgePadding;

	
	self.frame = safeRect;
	[CATransaction setDisableActions:NO];
	
	self.visible = YES;
	
	[UIView animateWithDuration:0.1 animations:^{
		self.alpha = 1;
	} completion:nil];
#endif
}

-(void)hide
{
#if USE_APPKIT_TOOLTIPS
	if (NSClassFromString(@"NSToolTipManager") && [NSClassFromString(@"NSToolTipManager") respondsToSelector:@selector(sharedToolTipManager)])
	{
		id manager = [NSClassFromString(@"NSToolTipManager") sharedToolTipManager];
		
		if (manager && [manager respondsToSelector:@selector(orderOutToolTipsImmediately:)])
		{
			[manager orderOutToolTipsImmediately:YES];
		}
	}
	
	self.visible = NO;
#else
	
	[UIView animateWithDuration:0.1 animations:^{
		self.alpha = 0;
	} completion:^(BOOL finished) {
		self.visible = NO;
	}];
#endif
}

@end
#endif

@implementation UIView (Tooltips)

#pragma mark - Properties


-(void)set_tooltipMouseOver:(BOOL)tooltipMouseOver
{
	objc_setAssociatedObject(self, @selector(_tooltipMouseOver), @(tooltipMouseOver), OBJC_ASSOCIATION_ASSIGN);
}

- (BOOL)_tooltipMouseOver
{
	return [objc_getAssociatedObject(self, @selector(_tooltipMouseOver)) boolValue];
}

#if !TARGET_OS_TV
-(void)set_tooltipRecognizer:(UIHoverGestureRecognizer *)obj
{
	objc_setAssociatedObject(self, @selector(_tooltipRecognizer), obj, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIHoverGestureRecognizer *)_tooltipRecognizer
{
	return objc_getAssociatedObject(self, @selector(_tooltipRecognizer));
}
#endif

-(void)setToolTip:(NSString *)obj
{
	objc_setAssociatedObject(self, @selector(toolTip), obj, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
	
#if !TARGET_OS_TV
	if (!self._tooltipRecognizer && obj && [obj length])
		[self _installTooltipRecognizer];
#endif
}

- (NSString *)toolTip
{
	return objc_getAssociatedObject(self, @selector(toolTip));
}

-(void)setToolTipRect:(CGRect)obj
{
	objc_setAssociatedObject(self, @selector(toolTipRect), @(obj), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (CGRect )toolTipRect
{
	NSValue *possibleRect = objc_getAssociatedObject(self, @selector(toolTipRect));
	
	if (possibleRect)
		return [possibleRect CGRectValue];
	
	return self.bounds;
}

-(void)setLastMouseLocation:(CGPoint)obj
{
	objc_setAssociatedObject(self, @selector(lastMouseLocation), @(obj), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (CGPoint )lastMouseLocation
{
	NSValue *possibleLocation = objc_getAssociatedObject(self, @selector(lastMouseLocation));
	
	if (possibleLocation)
		return [possibleLocation CGPointValue];
	
	return CGPointZero;
}

#pragma mark - Recognizer

-(void)_installTooltipRecognizer
{
#if !TARGET_OS_TV
	self._tooltipRecognizer = [[UIHoverGestureRecognizer alloc] initWithTarget:self action:@selector(tooltipHover:)];
    
    if (![[self class] isKindOfClass:[UIButton class]] || ([[self class] isKindOfClass:[UIButton class]] && ((UIButton *)self).buttonType != UIButtonTypeCustom))
    {
        [self addGestureRecognizer:self._tooltipRecognizer];
    }
    
#endif
	
#if SIMULATE_TOOLTIPS_ON_LONGPRESS
	self._tooltipRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(tooltipHover:)];
	[self addGestureRecognizer:self._tooltipRecognizer];
#endif
}

#if !TARGET_OS_TV
-(void)_beginTooltipTimer
{
	CGFloat time = 2.0;
	
	if ([UITooltipView sharedInstance].visible)
		time = 0.0;
	
	[NSTimer scheduledTimerWithTimeInterval:time repeats:NO block:^(NSTimer * _Nonnull timer) {
		if (self._tooltipMouseOver)
		{
			if (!CGRectContainsPoint(self.toolTipRect, self.lastMouseLocation))
			{
				return;
			}
			
			CGRect convertedRect = [self convertRect:self.bounds toView:self.window];
			
			[UITooltipView sharedInstance].tooltipLabel.text = self.toolTip;
			[self.window addSubview:[UITooltipView sharedInstance]];
			[[UITooltipView sharedInstance] showFromRect:convertedRect];
		}
	}];
}

-(void)tooltipHover:(UIHoverGestureRecognizer *)recognizer
{
	CGPoint p = [recognizer locationInView:self];
	self.lastMouseLocation = p;
	
	switch (recognizer.state)
	{
		case UIGestureRecognizerStateBegan:
		{
			self._tooltipMouseOver = YES;
			[self _beginTooltipTimer];
			
			break;
		}
		case UIGestureRecognizerStateChanged:
		{
			break;
		}
		case UIGestureRecognizerStateEnded:
		case UIGestureRecognizerStateCancelled:
		case UIGestureRecognizerStateFailed:
		{
			self._tooltipMouseOver = NO;
			[[UITooltipView sharedInstance] hide];
			
			break;
		}
		default:
			break;
	}
}
#endif
@end