components/Collections/src/private/MDCCollectionGridBackgroundView.m

// Copyright 2016-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 "MDCCollectionGridBackgroundView.h"

#import "MaterialCollectionLayoutAttributes.h"

@implementation MDCCollectionGridBackgroundView {
  UIImageView *_backgroundImageView;
}

- (instancetype)initWithFrame:(CGRect)frame {
  self = [super initWithFrame:frame];
  if (self) {
    [self commonMDCCollectionGridBackgroundViewInit];
  }
  return self;
}

- (instancetype)initWithCoder:(NSCoder *)aDecoder {
  self = [super initWithCoder:aDecoder];
  if (self) {
    [self commonMDCCollectionGridBackgroundViewInit];
  }
  return self;
}

- (void)commonMDCCollectionGridBackgroundViewInit {
  _backgroundImageView = [[UIImageView alloc] initWithFrame:self.bounds];
  _backgroundImageView.autoresizingMask =
      UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
  [self addSubview:_backgroundImageView];
}

- (void)applyLayoutAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes {
  [super applyLayoutAttributes:layoutAttributes];
  NSAssert([layoutAttributes isKindOfClass:[MDCCollectionViewLayoutAttributes class]],
           @"LayoutAttributes must be a subclass of MDCCollectionViewLayoutAttributes.");
  MDCCollectionViewLayoutAttributes *attr = (MDCCollectionViewLayoutAttributes *)layoutAttributes;
  _backgroundImageView.image = attr.backgroundImage;
}

@end