| // Copyright 2018-present the Material Components for iOS authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #import "MDCBottomDrawerPresentationController.h" |
| |
| #import "private/MDCBottomDrawerContainerViewController.h" |
| #import "MDCBottomDrawerPresentationControllerDelegate.h" |
| #import "MDCBottomDrawerViewController.h" |
| #import "MaterialPalettes.h" |
| |
| static CGFloat kTopHandleHeight = (CGFloat)2.0; |
| static CGFloat kTopHandleWidth = (CGFloat)24.0; |
| static CGFloat kTopHandleTopMargin = (CGFloat)5.0; |
| |
| /** View that allows touches that aren't handled from within the view to be propagated up the |
| responder chain. This is used to allow forwarding of tap events from the scrim view through to |
| the delegate if that has been enabled on the VC. */ |
| @interface MDCBottomDrawerScrimView : UIView |
| @end |
| |
| @implementation MDCBottomDrawerScrimView |
| |
| - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event { |
| // Cause the responder chain to keep bubbling up and propagate touches from the scrim view thru |
| // to the presenting VC to possibly be handled by the drawer delegate. |
| UIView *view = [super hitTest:point withEvent:event]; |
| return view == self ? nil : view; |
| } |
| |
| @end |
| |
| @interface MDCBottomDrawerPresentationController () <UIGestureRecognizerDelegate, |
| MDCBottomDrawerContainerViewControllerDelegate> |
| |
| /** |
| A semi-transparent scrim view that darkens the visible main view when the drawer is displayed. |
| */ |
| @property(nonatomic) UIView *scrimView; |
| |
| /** |
| The top handle view at the top of the drawer to provide a visual affordance for scrollability. |
| */ |
| @property(nonatomic) UIView *topHandle; |
| |
| /** |
| The bottom drawer container view controller. |
| */ |
| @property(nonatomic) MDCBottomDrawerContainerViewController *bottomDrawerContainerViewController; |
| |
| @end |
| |
| @implementation MDCBottomDrawerPresentationController { |
| UIColor *_scrimColor; |
| } |
| |
| @synthesize delegate; |
| |
| - (instancetype)initWithPresentedViewController:(UIViewController *)presentedViewController |
| presentingViewController:(UIViewController *)presentingViewController { |
| self = [super initWithPresentedViewController:presentedViewController |
| presentingViewController:presentingViewController]; |
| if (self) { |
| _topHandleHidden = YES; |
| _maximumInitialDrawerHeight = 0; |
| _maximumDrawerHeight = 0; |
| _drawerShadowColor = [UIColor.blackColor colorWithAlphaComponent:(CGFloat)0.2]; |
| _elevation = MDCShadowElevationNavDrawer; |
| _dismissOnBackgroundTap = YES; |
| _shouldDisplayMobileLandscapeFullscreen = YES; |
| } |
| return self; |
| } |
| |
| - (UIView *)presentedView { |
| if ([self.presentedViewController isKindOfClass:[MDCBottomDrawerViewController class]]) { |
| return super.presentedView; |
| } else { |
| // Override the presentedView property getter to return our container view controller's |
| // view instead of the default. |
| return self.bottomDrawerContainerViewController.view; |
| } |
| } |
| |
| - (void)presentationTransitionWillBegin { |
| MDCBottomDrawerContainerViewController *bottomDrawerContainerViewController = |
| [[MDCBottomDrawerContainerViewController alloc] |
| initWithOriginalPresentingViewController:self.presentingViewController |
| trackingScrollView:self.trackingScrollView]; |
| if (self.maximumInitialDrawerHeight > 0) { |
| bottomDrawerContainerViewController.maximumInitialDrawerHeight = |
| self.maximumInitialDrawerHeight; |
| } |
| if (self.maximumDrawerHeight > 0) { |
| bottomDrawerContainerViewController.maximumDrawerHeight = self.maximumDrawerHeight; |
| } |
| bottomDrawerContainerViewController.shouldIncludeSafeAreaInContentHeight = |
| self.shouldIncludeSafeAreaInContentHeight; |
| bottomDrawerContainerViewController.shouldIncludeSafeAreaInInitialDrawerHeight = |
| self.shouldIncludeSafeAreaInInitialDrawerHeight; |
| bottomDrawerContainerViewController.shouldUseStickyStatusBar = self.shouldUseStickyStatusBar; |
| bottomDrawerContainerViewController.shouldAdjustOnContentSizeChange = |
| self.shouldAdjustOnContentSizeChange; |
| bottomDrawerContainerViewController.shouldAlwaysExpandHeader = self.shouldAlwaysExpandHeader; |
| bottomDrawerContainerViewController.elevation = self.elevation; |
| bottomDrawerContainerViewController.drawerShadowColor = self.drawerShadowColor; |
| bottomDrawerContainerViewController.adjustLayoutForIPadSlideOver = |
| self.adjustLayoutForIPadSlideOver; |
| bottomDrawerContainerViewController.shouldDisplayMobileLandscapeFullscreen = |
| self.shouldDisplayMobileLandscapeFullscreen; |
| if ([self.presentedViewController isKindOfClass:[MDCBottomDrawerViewController class]]) { |
| // If in fact the presentedViewController is an MDCBottomDrawerViewController, |
| // we then know there is a content and an (optional) header view controller. |
| // We pass those view controllers to the MDCBottomDrawerContainerViewController that |
| // consists of the drawer logic. |
| MDCBottomDrawerViewController *bottomDrawerViewController = |
| (MDCBottomDrawerViewController *)self.presentedViewController; |
| self.delegate = bottomDrawerViewController; |
| bottomDrawerContainerViewController.contentViewController = |
| bottomDrawerViewController.contentViewController; |
| bottomDrawerContainerViewController.headerViewController = |
| bottomDrawerViewController.headerViewController; |
| } else { |
| bottomDrawerContainerViewController.contentViewController = self.presentedViewController; |
| } |
| bottomDrawerContainerViewController.animatingPresentation = YES; |
| self.bottomDrawerContainerViewController = bottomDrawerContainerViewController; |
| self.bottomDrawerContainerViewController.delegate = self; |
| |
| self.scrimView = [[MDCBottomDrawerScrimView alloc] initWithFrame:self.containerView.bounds]; |
| self.scrimView.backgroundColor = self.scrimColor; |
| self.scrimView.autoresizingMask = |
| UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; |
| self.scrimView.accessibilityIdentifier = @"Close drawer"; |
| self.scrimView.accessibilityTraits |= UIAccessibilityTraitButton; |
| |
| [self.containerView addSubview:self.scrimView]; |
| |
| self.topHandle = |
| [[UIView alloc] initWithFrame:CGRectMake(0, 0, kTopHandleWidth, kTopHandleHeight)]; |
| self.topHandle.layer.cornerRadius = kTopHandleHeight * (CGFloat)0.5; |
| self.topHandle.backgroundColor = self.topHandleColor ?: MDCPalette.greyPalette.tint300; |
| self.topHandle.hidden = self.topHandleHidden; |
| self.topHandle.translatesAutoresizingMaskIntoConstraints = NO; |
| UIView *handleSuperview = nil; |
| if (bottomDrawerContainerViewController.headerViewController) { |
| handleSuperview = bottomDrawerContainerViewController.headerViewController.view; |
| } else { |
| handleSuperview = bottomDrawerContainerViewController.contentViewController.view; |
| } |
| [handleSuperview addSubview:self.topHandle]; |
| [NSLayoutConstraint constraintWithItem:self.topHandle |
| attribute:NSLayoutAttributeTop |
| relatedBy:NSLayoutRelationEqual |
| toItem:handleSuperview |
| attribute:NSLayoutAttributeTop |
| multiplier:1.0 |
| constant:kTopHandleTopMargin] |
| .active = YES; |
| [NSLayoutConstraint constraintWithItem:self.topHandle |
| attribute:NSLayoutAttributeCenterX |
| relatedBy:NSLayoutRelationEqual |
| toItem:handleSuperview |
| attribute:NSLayoutAttributeCenterX |
| multiplier:1.0 |
| constant:0] |
| .active = YES; |
| [NSLayoutConstraint constraintWithItem:self.topHandle |
| attribute:NSLayoutAttributeWidth |
| relatedBy:NSLayoutRelationEqual |
| toItem:nil |
| attribute:NSLayoutAttributeNotAnAttribute |
| multiplier:1.0 |
| constant:kTopHandleWidth] |
| .active = YES; |
| [NSLayoutConstraint constraintWithItem:self.topHandle |
| attribute:NSLayoutAttributeHeight |
| relatedBy:NSLayoutRelationEqual |
| toItem:nil |
| attribute:NSLayoutAttributeNotAnAttribute |
| multiplier:1.0 |
| constant:kTopHandleHeight] |
| .active = YES; |
| if ([self.presentedViewController isKindOfClass:[MDCBottomDrawerViewController class]]) { |
| [self.presentedView addSubview:self.bottomDrawerContainerViewController.view]; |
| [self.presentedViewController addChildViewController:self.bottomDrawerContainerViewController]; |
| } else { |
| [self.containerView addSubview:self.bottomDrawerContainerViewController.view]; |
| } |
| |
| if (self.adjustLayoutForIPadSlideOver) { |
| [self setupBottomDrawerContainerViewControllerConstraints]; |
| } |
| |
| id<UIViewControllerTransitionCoordinator> transitionCoordinator = |
| [[self presentingViewController] transitionCoordinator]; |
| |
| // Fade in the scrim view during the transition. |
| self.scrimView.alpha = 0.0; |
| [transitionCoordinator |
| animateAlongsideTransition:^(id<UIViewControllerTransitionCoordinatorContext> context) { |
| self.scrimView.alpha = 1.0; |
| } |
| completion:nil]; |
| |
| // Need to calculate the initial position of the drawer since the layout pass will |
| // not be complete before the animation begins. |
| CGRect frame = [self targetFrameOfDrawerContentOnPresentation]; |
| [self.delegate bottomDrawerPresentTransitionWillBegin:self |
| withCoordinator:transitionCoordinator |
| targetYOffset:frame.origin.y]; |
| } |
| |
| /** |
| Setup constraints so bottomDrawerContainerViewController has the correct size in iPad Slide Over. |
| |
| Without these constraints when the app is in iPad Slide Over, the view controller will |
| have the wrong size that is equal to the screen when it should instead be the size of the Slide |
| Over window. |
| */ |
| - (void)setupBottomDrawerContainerViewControllerConstraints { |
| UIView *bottomDrawerView = self.bottomDrawerContainerViewController.view; |
| UIView *bottomDrawerSuperview = bottomDrawerView.superview; |
| |
| bottomDrawerView.translatesAutoresizingMaskIntoConstraints = NO; |
| [NSLayoutConstraint activateConstraints:@[ |
| [bottomDrawerView.leftAnchor constraintEqualToAnchor:bottomDrawerSuperview.leftAnchor], |
| [bottomDrawerView.rightAnchor constraintEqualToAnchor:bottomDrawerSuperview.rightAnchor], |
| [bottomDrawerView.topAnchor constraintEqualToAnchor:bottomDrawerSuperview.topAnchor], |
| [bottomDrawerView.bottomAnchor constraintEqualToAnchor:bottomDrawerSuperview.bottomAnchor], |
| ]]; |
| } |
| |
| - (void)presentationTransitionDidEnd:(BOOL)completed { |
| if (!self.shouldForwardBackgroundTouchEvents) { |
| // Set up the tap recognizer. |
| UITapGestureRecognizer *tapGestureRecognizer = |
| [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(scrimTapped)]; |
| [self.containerView addGestureRecognizer:tapGestureRecognizer]; |
| tapGestureRecognizer.delegate = self; |
| } |
| |
| self.bottomDrawerContainerViewController.animatingPresentation = NO; |
| [self.bottomDrawerContainerViewController.view setNeedsLayout]; |
| if (!completed) { |
| [self.scrimView removeFromSuperview]; |
| [self.topHandle removeFromSuperview]; |
| } |
| |
| [self.delegate bottomDrawerPresentTransitionDidEnd:self]; |
| } |
| |
| - (void)dismissalTransitionWillBegin { |
| self.bottomDrawerContainerViewController.animatingDismissal = YES; |
| |
| id<UIViewControllerTransitionCoordinator> transitionCoordinator = |
| [[self presentingViewController] transitionCoordinator]; |
| [transitionCoordinator |
| animateAlongsideTransition:^(id<UIViewControllerTransitionCoordinatorContext> context) { |
| self.scrimView.alpha = 0.0; |
| } |
| completion:nil]; |
| |
| [self.delegate bottomDrawerDismissTransitionWillBegin:self |
| withCoordinator:transitionCoordinator |
| targetYOffset:self.containerView.frame.size.height]; |
| } |
| |
| - (void)dismissalTransitionDidEnd:(BOOL)completed { |
| if (completed) { |
| if ([self.presentedViewController isKindOfClass:[MDCBottomDrawerViewController class]]) { |
| CGRect newFrame = CGRectStandardize( |
| self.bottomDrawerContainerViewController.contentViewController.view.frame); |
| newFrame.size.height -= self.bottomDrawerContainerViewController.addedHeight; |
| self.bottomDrawerContainerViewController.contentViewController.view.frame = newFrame; |
| [self.bottomDrawerContainerViewController willMoveToParentViewController:nil]; |
| [self.bottomDrawerContainerViewController.view removeFromSuperview]; |
| [self.bottomDrawerContainerViewController removeFromParentViewController]; |
| } |
| [self.scrimView removeFromSuperview]; |
| [self.topHandle removeFromSuperview]; |
| } |
| |
| self.bottomDrawerContainerViewController.animatingDismissal = NO; |
| [self.delegate bottomDrawerDismissTransitionDidEnd:self]; |
| } |
| |
| - (void)preferredContentSizeDidChangeForChildContentContainer:(id<UIContentContainer>)container { |
| [super preferredContentSizeDidChangeForChildContentContainer:container]; |
| [self.bottomDrawerContainerViewController.view layoutIfNeeded]; |
| } |
| |
| /** Estimate the target frame of the drawer content upon presentation. */ |
| - (CGRect)targetFrameOfDrawerContentOnPresentation { |
| CGSize containerSize = self.containerView.frame.size; |
| CGSize preferredSize = self.presentedViewController.preferredContentSize; |
| |
| // Layout has yet to be completed so let's calculate the preferred height. |
| if (CGSizeEqualToSize(preferredSize, CGSizeZero)) { |
| preferredSize.height = self.bottomDrawerContainerViewController.maximumInitialDrawerHeight; |
| preferredSize.width = containerSize.width; |
| } |
| |
| return CGRectMake(0, MAX(0.0f, containerSize.height - preferredSize.height), preferredSize.height, |
| preferredSize.width); |
| } |
| |
| - (void)viewWillTransitionToSize:(CGSize)size |
| withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator { |
| [super viewWillTransitionToSize:size withTransitionCoordinator:coordinator]; |
| [self.bottomDrawerContainerViewController viewWillTransitionToSize:size |
| withTransitionCoordinator:coordinator]; |
| } |
| |
| - (void)traitCollectionDidChange:(UITraitCollection *)previousTraitCollection { |
| [super traitCollectionDidChange:previousTraitCollection]; |
| |
| if (self.traitCollectionDidChangeBlock) { |
| self.traitCollectionDidChangeBlock(self, previousTraitCollection); |
| } |
| } |
| |
| - (void)setScrimColor:(UIColor *)scrimColor { |
| _scrimColor = scrimColor; |
| self.scrimView.backgroundColor = scrimColor; |
| } |
| |
| - (UIColor *)scrimColor { |
| return _scrimColor ?: [UIColor colorWithWhite:0 alpha:(CGFloat)0.32]; |
| } |
| |
| - (void)setTopHandleHidden:(BOOL)topHandleHidden { |
| _topHandleHidden = topHandleHidden; |
| self.topHandle.hidden = topHandleHidden; |
| } |
| |
| - (void)setTopHandleColor:(UIColor *)topHandleColor { |
| _topHandleColor = topHandleColor; |
| self.topHandle.backgroundColor = topHandleColor; |
| } |
| |
| - (void)setElevation:(MDCShadowElevation)elevation { |
| _elevation = elevation; |
| self.bottomDrawerContainerViewController.elevation = elevation; |
| } |
| |
| - (void)setShouldAlwaysExpandHeader:(BOOL)shouldAlwaysExpandHeader { |
| _shouldAlwaysExpandHeader = shouldAlwaysExpandHeader; |
| self.bottomDrawerContainerViewController.shouldAlwaysExpandHeader = shouldAlwaysExpandHeader; |
| } |
| |
| - (void)setShouldAdjustOnContentSizeChange:(BOOL)shouldAdjustOnContentSizeChange { |
| _shouldAdjustOnContentSizeChange = shouldAdjustOnContentSizeChange; |
| self.bottomDrawerContainerViewController.shouldAdjustOnContentSizeChange = |
| shouldAdjustOnContentSizeChange; |
| } |
| |
| - (void)setDrawerShadowColor:(UIColor *)drawerShadowColor { |
| _drawerShadowColor = drawerShadowColor; |
| self.bottomDrawerContainerViewController.drawerShadowColor = drawerShadowColor; |
| } |
| |
| - (void)setTrackingScrollView:(UIScrollView *)trackingScrollView { |
| _trackingScrollView = trackingScrollView; |
| self.bottomDrawerContainerViewController.trackingScrollView = trackingScrollView; |
| } |
| |
| - (BOOL)userDraggingEnabled { |
| return self.bottomDrawerContainerViewController.userDraggingEnabled; |
| } |
| |
| - (void)setUserDraggingEnabled:(BOOL)userDraggingEnabled { |
| self.bottomDrawerContainerViewController.userDraggingEnabled = userDraggingEnabled; |
| } |
| |
| - (void)setMaximumInitialDrawerHeight:(CGFloat)maximumInitialDrawerHeight { |
| _maximumInitialDrawerHeight = maximumInitialDrawerHeight; |
| self.bottomDrawerContainerViewController.maximumInitialDrawerHeight = |
| self.maximumInitialDrawerHeight; |
| } |
| |
| - (void)setMaximumDrawerHeight:(CGFloat)maximumDrawerHeight { |
| _maximumDrawerHeight = maximumDrawerHeight; |
| self.bottomDrawerContainerViewController.maximumDrawerHeight = self.maximumDrawerHeight; |
| } |
| |
| - (BOOL)contentReachesFullscreen { |
| return self.bottomDrawerContainerViewController.contentReachesFullscreen; |
| } |
| |
| #pragma mark - Private |
| |
| - (void)hideDrawer { |
| [self.presentingViewController dismissViewControllerAnimated:YES completion:nil]; |
| } |
| |
| - (void)scrimTapped { |
| [self.delegate bottomDrawerDidTapScrim:self]; |
| |
| // Dismiss the drawer on tap if enabled. |
| if (self.dismissOnBackgroundTap) { |
| [self hideDrawer]; |
| } |
| } |
| |
| #pragma mark UIGestureRecognizerDelegate |
| |
| - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer |
| shouldReceiveTouch:(UITouch *)touch { |
| return [self.bottomDrawerContainerViewController gestureRecognizer:gestureRecognizer |
| shouldReceiveTouch:touch]; |
| } |
| |
| #pragma mark - MDCBottomDrawerContainerViewControllerDelegate |
| |
| - (void)bottomDrawerContainerViewControllerWillChangeState: |
| (MDCBottomDrawerContainerViewController *)containerViewController |
| drawerState:(MDCBottomDrawerState)drawerState { |
| id<MDCBottomDrawerPresentationControllerDelegate> strongDelegate = self.delegate; |
| if ([strongDelegate respondsToSelector:@selector(bottomDrawerWillChangeState:drawerState:)]) { |
| [strongDelegate bottomDrawerWillChangeState:self drawerState:drawerState]; |
| } |
| } |
| |
| - (void)bottomDrawerContainerViewControllerTopTransitionRatio: |
| (MDCBottomDrawerContainerViewController *)containerViewController |
| transitionRatio:(CGFloat)transitionRatio { |
| id<MDCBottomDrawerPresentationControllerDelegate> strongDelegate = self.delegate; |
| if ([strongDelegate respondsToSelector:@selector(bottomDrawerTopTransitionRatio: |
| transitionRatio:)]) { |
| [strongDelegate bottomDrawerTopTransitionRatio:self transitionRatio:transitionRatio]; |
| self.topHandle.alpha = (CGFloat)1.0 - transitionRatio; |
| } |
| } |
| |
| - (void)setContentOffsetY:(CGFloat)contentOffsetY animated:(BOOL)animated { |
| [self.bottomDrawerContainerViewController setContentOffsetY:contentOffsetY animated:animated]; |
| } |
| |
| - (void)expandToFullscreenWithDuration:(CGFloat)duration |
| completion:(void (^__nullable)(BOOL finished))completion { |
| [self.bottomDrawerContainerViewController expandToFullscreenWithDuration:duration |
| completion:completion]; |
| } |
| |
| - (void)bottomDrawerContainerViewControllerDidChangeYOffset: |
| (MDCBottomDrawerContainerViewController *)containerViewController |
| yOffset:(CGFloat)yOffset { |
| id<MDCBottomDrawerPresentationControllerDelegate> strongDelegate = self.delegate; |
| if ([strongDelegate respondsToSelector:@selector(bottomDrawerTopDidChangeYOffset:yOffset:)]) { |
| [strongDelegate bottomDrawerTopDidChangeYOffset:self yOffset:yOffset]; |
| } |
| } |
| |
| - (void)bottomDrawerContainerViewControllerNeedsScrimAppearanceUpdate: |
| (nonnull MDCBottomDrawerContainerViewController *)containerViewController |
| scrimShouldAdoptTrackingScrollViewBackgroundColor: |
| (BOOL)scrimShouldAdoptTrackingScrollViewBackgroundColor { |
| if (self.trackingScrollView) { |
| // This logic is to mitigate b/119714330. Dragging the drawer further up when already at the |
| // bottom shows the scrim and the presenting view controller |
| self.scrimView.backgroundColor = scrimShouldAdoptTrackingScrollViewBackgroundColor |
| ? self.trackingScrollView.backgroundColor |
| : self.scrimColor; |
| } |
| } |
| |
| @end |
