react-native-toast/ios/RCTToast/Toast+UIView.m

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

/*
 *  CONFIGURE THESE VALUES TO ADJUST LOOK & FEEL,
 *  DISPLAY DURATION, ETC.
 */

// general appearance
static const CGFloat CSToastMaxWidth            = 0.8;      // 80% of parent view width
static const CGFloat CSToastMaxHeight           = 0.8;      // 80% of parent view height
static const CGFloat CSToastHorizontalPadding   = 10.0;
static const CGFloat CSToastVerticalPadding     = 10.0;
static const CGFloat CSToastTopBottomOffset     = 20.0;
static const CGFloat CSToastCornerRadius        = 5.0;
static const CGFloat CSToastOpacity             = 0.8;
static const CGFloat CSToastFontSize            = 16.0;
static const CGFloat CSToastMaxTitleLines       = 0;
static const CGFloat CSToastMaxMessageLines     = 0;
static const NSTimeInterval CSToastFadeDuration = 0.2;

// shadow appearance
static const CGFloat CSToastShadowOpacity       = 0.8;
static const CGFloat CSToastShadowRadius        = 6.0;
static const CGSize  CSToastShadowOffset        = { 4.0, 4.0 };
static const BOOL    CSToastDisplayShadow       = YES;

// display duration and position
static const NSString * CSToastDefaultPosition  = @"bottom";
static const NSTimeInterval CSToastDefaultDuration  = 1.5;

// image view size
static const CGFloat CSToastImageViewWidth      = 80.0;
static const CGFloat CSToastImageViewHeight     = 80.0;

// activity
static const CGFloat CSToastActivityWidth       = 100.0;
static const CGFloat CSToastActivityHeight      = 100.0;
static const NSString * CSToastActivityDefaultPosition = @"center";

// interaction
static const BOOL CSToastHidesOnTap             = YES;     // excludes activity views

// associative reference keys
static const NSString * CSToastTimerKey         = @"CSToastTimerKey";
static const NSString * CSToastActivityViewKey  = @"CSToastActivityViewKey";

static UIView *prevToast = NULL;

@interface UIView (ToastPrivate)

- (void)hideToast:(UIView *)toast;
- (void)toastTimerDidFinish:(NSTimer *)timer;
- (void)handleToastTapped:(UITapGestureRecognizer *)recognizer;
- (CGPoint)centerPointForPosition:(id)position withToast:(UIView *)toast withAddedPixelsY:(int) addPixelsY;
- (UIView *)viewForMessage:(NSString *)message title:(NSString *)title image:(UIImage *)image;
- (CGSize)sizeForString:(NSString *)string font:(UIFont *)font constrainedToSize:(CGSize)constrainedSize lineBreakMode:(NSLineBreakMode)lineBreakMode;

@end


@implementation UIView (Toast)

#pragma mark - Toast Methods

- (void)makeToast:(NSString *)message {
    [self makeToast:message duration:CSToastDefaultDuration position:CSToastDefaultPosition];
}

- (void)makeToast:(NSString *)message duration:(NSTimeInterval)duration position:(id)position {
    UIView *toast = [self viewForMessage:message title:nil image:nil];
    [self showToast:toast duration:duration position:position];
}

- (void)makeToast:(NSString *)message duration:(NSTimeInterval)duration position:(id)position addPixelsY:(int)addPixelsY {
  UIView *toast = [self viewForMessage:message title:nil image:nil];
  [self showToast:toast duration:duration position:position addedPixelsY:addPixelsY];
}

- (void)makeToast:(NSString *)message duration:(NSTimeInterval)duration position:(id)position title:(NSString *)title {
    UIView *toast = [self viewForMessage:message title:title image:nil];
    [self showToast:toast duration:duration position:position];
}

- (void)makeToast:(NSString *)message duration:(NSTimeInterval)duration position:(id)position image:(UIImage *)image {
    UIView *toast = [self viewForMessage:message title:nil image:image];
    [self showToast:toast duration:duration position:position];
}

- (void)makeToast:(NSString *)message duration:(NSTimeInterval)duration  position:(id)position title:(NSString *)title image:(UIImage *)image {
    UIView *toast = [self viewForMessage:message title:title image:image];
    [self showToast:toast duration:duration position:position];
}

- (void)showToast:(UIView *)toast {
    [self showToast:toast duration:CSToastDefaultDuration position:CSToastDefaultPosition];
}

- (void)showToast:(UIView *)toast duration:(NSTimeInterval)duration position:(id)point {
  [self showToast:toast duration:CSToastDefaultDuration position:CSToastDefaultPosition addedPixelsY:0];
}

- (void)showToast:(UIView *)toast duration:(NSTimeInterval)duration position:(id)point addedPixelsY:(int) addPixelsY  {
    [self hideToast];
    prevToast = toast;
    toast.center = [self centerPointForPosition:point withToast:toast withAddedPixelsY:addPixelsY];
    toast.alpha = 0.0;

    if (CSToastHidesOnTap) {
        UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:toast action:@selector(handleToastTapped:)];
        [toast addGestureRecognizer:recognizer];
        toast.userInteractionEnabled = YES;
        toast.exclusiveTouch = YES;
    }

    // make sure that if InAppBrowser is active, we're still showing Toasts on top of it
    UIViewController *vc = [self getTopMostViewController];
    UIView *v = [vc view];
    [v addSubview:toast];

    [UIView animateWithDuration:CSToastFadeDuration
                          delay:0.0
                        options:(UIViewAnimationOptionCurveEaseOut | UIViewAnimationOptionAllowUserInteraction)
                     animations:^{
                         toast.alpha = CSToastOpacity;
                     } completion:^(BOOL finished) {
                         NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:duration target:self selector:@selector(toastTimerDidFinish:) userInfo:toast repeats:NO];
                         // associate the timer with the toast view
                         objc_setAssociatedObject (toast, &CSToastTimerKey, timer, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
                     }];

}

- (UIViewController*) getTopMostViewController {
  UIViewController *presentingViewController = [[[UIApplication sharedApplication] delegate] window].rootViewController;
  while (presentingViewController.presentedViewController != nil) {
    presentingViewController = presentingViewController.presentedViewController;
  }
  return presentingViewController;
}

- (void)hideToast {
  if (prevToast){
    [self hideToast:prevToast];
  }
}

- (void)hideToast:(UIView *)toast {
    [UIView animateWithDuration:CSToastFadeDuration
                          delay:0.0
                        options:(UIViewAnimationOptionCurveEaseIn | UIViewAnimationOptionBeginFromCurrentState)
                     animations:^{
                         toast.alpha = 0.0;
                     } completion:^(BOOL finished) {
                         [toast removeFromSuperview];
                     }];
}

#pragma mark - Events

- (void)toastTimerDidFinish:(NSTimer *)timer {
    [self hideToast:(UIView *)timer.userInfo];
}

- (void)handleToastTapped:(UITapGestureRecognizer *)recognizer {
    NSTimer *timer = (NSTimer *)objc_getAssociatedObject(self, &CSToastTimerKey);
    [timer invalidate];

    [self hideToast:recognizer.view];
}

#pragma mark - Toast Activity Methods

- (void)makeToastActivity {
    [self makeToastActivity:CSToastActivityDefaultPosition];
}

- (void)makeToastActivity:(id)position {
    // sanity
    UIView *existingActivityView = (UIView *)objc_getAssociatedObject(self, &CSToastActivityViewKey);
    if (existingActivityView != nil) return;

    UIView *activityView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, CSToastActivityWidth, CSToastActivityHeight)];
    activityView.center = [self centerPointForPosition:position withToast:activityView withAddedPixelsY:0];
    activityView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:CSToastOpacity];
    activityView.alpha = 0.0;
    activityView.autoresizingMask = (UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin);
    activityView.layer.cornerRadius = CSToastCornerRadius;

    if (CSToastDisplayShadow) {
        activityView.layer.shadowColor = [UIColor blackColor].CGColor;
        activityView.layer.shadowOpacity = CSToastShadowOpacity;
        activityView.layer.shadowRadius = CSToastShadowRadius;
        activityView.layer.shadowOffset = CSToastShadowOffset;
    }

    UIActivityIndicatorView *activityIndicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
    activityIndicatorView.center = CGPointMake(activityView.bounds.size.width / 2, activityView.bounds.size.height / 2);
    [activityView addSubview:activityIndicatorView];
    [activityIndicatorView startAnimating];

    // associate the activity view with self
    objc_setAssociatedObject (self, &CSToastActivityViewKey, activityView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

    [self addSubview:activityView];

    [UIView animateWithDuration:CSToastFadeDuration
                          delay:0.0
                        options:UIViewAnimationOptionCurveEaseOut
                     animations:^{
                         activityView.alpha = 1.0;
                     } completion:nil];
}

- (void)hideToastActivity {
    UIView *existingActivityView = (UIView *)objc_getAssociatedObject(self, &CSToastActivityViewKey);
    if (existingActivityView != nil) {
        [UIView animateWithDuration:CSToastFadeDuration
                              delay:0.0
                            options:(UIViewAnimationOptionCurveEaseIn | UIViewAnimationOptionBeginFromCurrentState)
                         animations:^{
                             existingActivityView.alpha = 0.0;
                         } completion:^(BOOL finished) {
                             [existingActivityView removeFromSuperview];
                             objc_setAssociatedObject (self, &CSToastActivityViewKey, nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
                         }];
    }
}

#pragma mark - Helpers

- (CGPoint)centerPointForPosition:(id)point withToast:(UIView *)toast withAddedPixelsY:(int) addPixelsY {
    if([point isKindOfClass:[NSString class]]) {
        // convert string literals @"top", @"bottom", @"center", or any point wrapped in an NSValue object into a CGPoint
        if([point caseInsensitiveCompare:@"top"] == NSOrderedSame) {
            return CGPointMake(self.bounds.size.width/2, (toast.frame.size.height / 2) + addPixelsY + CSToastVerticalPadding + CSToastTopBottomOffset);
        } else if([point caseInsensitiveCompare:@"bottom"] == NSOrderedSame) {
            return CGPointMake(self.bounds.size.width/2, (self.bounds.size.height - (toast.frame.size.height / 2)) - CSToastVerticalPadding - CSToastTopBottomOffset + addPixelsY);
        } else if([point caseInsensitiveCompare:@"center"] == NSOrderedSame) {
            return CGPointMake(self.bounds.size.width / 2, (self.bounds.size.height / 2) + addPixelsY);
        }
    } else if ([point isKindOfClass:[NSValue class]]) {
        return [point CGPointValue];
    }

    NSLog(@"Warning: Invalid position for toast.");
    return [self centerPointForPosition:CSToastDefaultPosition withToast:toast withAddedPixelsY:addPixelsY];
}

- (CGSize)sizeForString:(NSString *)string font:(UIFont *)font constrainedToSize:(CGSize)constrainedSize lineBreakMode:(NSLineBreakMode)lineBreakMode {
    if ([string respondsToSelector:@selector(boundingRectWithSize:options:attributes:context:)]) {
        NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
        paragraphStyle.lineBreakMode = lineBreakMode;
        NSDictionary *attributes = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paragraphStyle};
        CGRect boundingRect = [string boundingRectWithSize:constrainedSize options:NSStringDrawingUsesLineFragmentOrigin attributes:attributes context:nil];
        return CGSizeMake(ceilf(boundingRect.size.width), ceilf(boundingRect.size.height));
    }

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
    return [string sizeWithFont:font constrainedToSize:constrainedSize lineBreakMode:lineBreakMode];
#pragma clang diagnostic pop
}

- (UIView *)viewForMessage:(NSString *)message title:(NSString *)title image:(UIImage *)image {
    // sanity
    if((message == nil) && (title == nil) && (image == nil)) return nil;

    // dynamically build a toast view with any combination of message, title, & image.
    UILabel *messageLabel = nil;
    UILabel *titleLabel = nil;
    UIImageView *imageView = nil;
    
    // create the parent view
    UIView *wrapperView = [[UIView alloc] init];
    wrapperView.autoresizingMask = (UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin);
    wrapperView.layer.cornerRadius = CSToastCornerRadius;
    
    if (CSToastDisplayShadow) {
        wrapperView.layer.shadowColor = [UIColor blackColor].CGColor;
        wrapperView.layer.shadowOpacity = CSToastShadowOpacity;
        wrapperView.layer.shadowRadius = CSToastShadowRadius;
        wrapperView.layer.shadowOffset = CSToastShadowOffset;
    }

    wrapperView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:CSToastOpacity];
    
    if(image != nil) {
        imageView = [[UIImageView alloc] initWithImage:image];
        imageView.contentMode = UIViewContentModeScaleAspectFit;
        imageView.frame = CGRectMake(CSToastHorizontalPadding, CSToastVerticalPadding, CSToastImageViewWidth, CSToastImageViewHeight);
    }
    
    CGFloat imageWidth, imageHeight, imageLeft;
    
    // the imageView frame values will be used to size & position the other views
    if(imageView != nil) {
        imageWidth = imageView.bounds.size.width;
        imageHeight = imageView.bounds.size.height;
        imageLeft = CSToastHorizontalPadding;
    } else {
        imageWidth = imageHeight = imageLeft = 0.0;
    }
    
    if (title != nil) {
        titleLabel = [[UILabel alloc] init];
        titleLabel.numberOfLines = CSToastMaxTitleLines;
        titleLabel.font = [UIFont boldSystemFontOfSize:CSToastFontSize];
        titleLabel.textAlignment = NSTextAlignmentLeft;
        titleLabel.lineBreakMode = NSLineBreakByWordWrapping;
        titleLabel.textColor = [UIColor whiteColor];
        titleLabel.backgroundColor = [UIColor clearColor];
        titleLabel.alpha = 1.0;
        titleLabel.text = title;
        
        // size the title label according to the length of the text
        CGSize maxSizeTitle = CGSizeMake((self.bounds.size.width * CSToastMaxWidth) - imageWidth, self.bounds.size.height * CSToastMaxHeight);
        CGSize expectedSizeTitle = [self sizeForString:title font:titleLabel.font constrainedToSize:maxSizeTitle lineBreakMode:titleLabel.lineBreakMode];
        titleLabel.frame = CGRectMake(0.0, 0.0, expectedSizeTitle.width, expectedSizeTitle.height);
    }
    
    if (message != nil) {
        messageLabel = [[UILabel alloc] init];
        messageLabel.numberOfLines = CSToastMaxMessageLines;
        messageLabel.font = [UIFont systemFontOfSize:CSToastFontSize];
        messageLabel.lineBreakMode = NSLineBreakByWordWrapping;
        messageLabel.textColor = [UIColor whiteColor];
        messageLabel.backgroundColor = [UIColor clearColor];
        messageLabel.alpha = 1.0;
        messageLabel.text = message;
        
        // size the message label according to the length of the text
        CGSize maxSizeMessage = CGSizeMake((self.bounds.size.width * CSToastMaxWidth) - imageWidth, self.bounds.size.height * CSToastMaxHeight);
        CGSize expectedSizeMessage = [self sizeForString:message font:messageLabel.font constrainedToSize:maxSizeMessage lineBreakMode:messageLabel.lineBreakMode];
        messageLabel.frame = CGRectMake(0.0, 0.0, expectedSizeMessage.width, expectedSizeMessage.height);
    }
    
    // titleLabel frame values
    CGFloat titleWidth, titleHeight, titleTop, titleLeft;
    
    if(titleLabel != nil) {
        titleWidth = titleLabel.bounds.size.width;
        titleHeight = titleLabel.bounds.size.height;
        titleTop = CSToastVerticalPadding;
        titleLeft = imageLeft + imageWidth + CSToastHorizontalPadding;
    } else {
        titleWidth = titleHeight = titleTop = titleLeft = 0.0;
    }
    
    // messageLabel frame values
    CGFloat messageWidth, messageHeight, messageLeft, messageTop;

    if(messageLabel != nil) {
        messageWidth = messageLabel.bounds.size.width;
        messageHeight = messageLabel.bounds.size.height;
        messageLeft = imageLeft + imageWidth + CSToastHorizontalPadding;
        messageTop = titleTop + titleHeight + CSToastVerticalPadding;
    } else {
        messageWidth = messageHeight = messageLeft = messageTop = 0.0;
    }

    CGFloat longerWidth = MAX(titleWidth, messageWidth);
    CGFloat longerLeft = MAX(titleLeft, messageLeft);
    
    // wrapper width uses the longerWidth or the image width, whatever is larger. same logic applies to the wrapper height
    CGFloat wrapperWidth = MAX((imageWidth + (CSToastHorizontalPadding * 2)), (longerLeft + longerWidth + CSToastHorizontalPadding));    
    CGFloat wrapperHeight = MAX((messageTop + messageHeight + CSToastVerticalPadding), (imageHeight + (CSToastVerticalPadding * 2)));
                         
    wrapperView.frame = CGRectMake(0.0, 0.0, wrapperWidth, wrapperHeight);
    
    if(titleLabel != nil) {
        titleLabel.frame = CGRectMake(titleLeft, titleTop, titleWidth, titleHeight);
        [wrapperView addSubview:titleLabel];
    }
    
    if(messageLabel != nil) {
        messageLabel.frame = CGRectMake(messageLeft, messageTop, messageWidth, messageHeight);
        [wrapperView addSubview:messageLabel];
    }
    
    if(imageView != nil) {
        [wrapperView addSubview:imageView];
    }
        
    return wrapperView;
}

@end