components/BottomSheet/src/MDCBottomSheetController.m

/*
 Copyright 2017-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 "MDCBottomSheetController.h"

#import "MDCBottomSheetPresentationController.h"
#import "MDCBottomSheetTransitionController.h"
#import "UIViewController+MaterialBottomSheet.h"

@interface MDCBottomSheetController () <MDCBottomSheetPresentationControllerDelegate>
@end

@implementation MDCBottomSheetController {
  MDCBottomSheetTransitionController *_transitionController;
}

- (nonnull instancetype)initWithContentViewController:
    (nonnull UIViewController *)contentViewController {
  if (self = [super initWithNibName:nil bundle:nil]) {
    _contentViewController = contentViewController;
    _transitionController = [[MDCBottomSheetTransitionController alloc] init];
    _transitionController.dismissOnBackgroundTap = YES;
    super.transitioningDelegate = _transitionController;
    super.modalPresentationStyle = UIModalPresentationCustom;
  }
  return self;
}

- (void)viewDidLoad {
  [super viewDidLoad];

  self.contentViewController.view.autoresizingMask =
      UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
  self.contentViewController.view.frame = self.view.bounds;

  [self addChildViewController:self.contentViewController];
  [self.view addSubview:self.contentViewController.view];
  [self.contentViewController didMoveToParentViewController:self];
}

- (void)viewWillAppear:(BOOL)animated {
  [super viewWillAppear:animated];

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
  self.mdc_bottomSheetPresentationController.delegate = self;
#pragma clang diagnostic pop

  self.mdc_bottomSheetPresentationController.dismissOnBackgroundTap =
      _transitionController.dismissOnBackgroundTap;

  [self.contentViewController.view layoutIfNeeded];
}

- (UIInterfaceOrientationMask)supportedInterfaceOrientations {
  return self.contentViewController.supportedInterfaceOrientations;
}

- (BOOL)accessibilityPerformEscape {
  if (!self.dismissOnBackgroundTap) {
    return NO;
  }
  [self dismissViewControllerAnimated:YES completion:nil];
  return YES;
}

- (CGSize)preferredContentSize {
  return self.contentViewController.preferredContentSize;
}

- (void)setPreferredContentSize:(CGSize)preferredContentSize {
  self.contentViewController.preferredContentSize = preferredContentSize;
}

- (void)preferredContentSizeDidChangeForChildContentContainer:(id<UIContentContainer>)container {
  [super preferredContentSizeDidChangeForChildContentContainer:container];
  // Informing the presentation controller of the change in preferred content size needs to be done
  // directly since the MDCBottomSheetController's preferredContentSize property is backed by
  // contentViewController's preferredContentSize. Therefore |[super setPreferredContentSize:]| is
  // never called, and UIKit never calls |preferredContentSizeDidChangeForChildContentContainer:|
  // on the presentation controller.
  [self.presentationController preferredContentSizeDidChangeForChildContentContainer:self];
}

- (UIScrollView *)trackingScrollView {
  return _transitionController.trackingScrollView;
}

- (void)setTrackingScrollView:(UIScrollView *)trackingScrollView {
  _transitionController.trackingScrollView = trackingScrollView;
}

- (BOOL)dismissOnBackgroundTap {
  return _transitionController.dismissOnBackgroundTap;
}

- (void)setDismissOnBackgroundTap:(BOOL)dismissOnBackgroundTap {
  _transitionController.dismissOnBackgroundTap = dismissOnBackgroundTap;
  self.mdc_bottomSheetPresentationController.dismissOnBackgroundTap = dismissOnBackgroundTap;
}

/* Disable setter. Always use internal transition controller */
- (void)setTransitioningDelegate:
    (__unused id<UIViewControllerTransitioningDelegate>)transitioningDelegate {
  NSAssert(NO, @"MDCBottomSheetController.transitioningDelegate cannot be changed.");
  return;
}

/* Disable setter. Always use custom presentation style */
- (void)setModalPresentationStyle:(__unused UIModalPresentationStyle)modalPresentationStyle {
  NSAssert(NO, @"MDCBottomSheetController.modalPresentationStyle cannot be changed.");
  return;
}

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
- (void)bottomSheetPresentationControllerDidDismissBottomSheet:
    (nonnull __unused MDCBottomSheetPresentationController *)bottomSheet {
#pragma clang diagnostic pop
  [self.delegate bottomSheetControllerDidDismissBottomSheet:self];
}

@end