material-components_material-components-ios/components/Tabs/examples/MDCTabBarViewTypicalExampleViewController.m

// Copyright 2019-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 <UIKit/UIKit.h>

#import <MaterialComponents/MaterialContainerScheme.h>
#import "MaterialTabs+TabBarView.h"

static NSString *const kExampleTitle = @"TabBarView";

/** A custom view to place in an MDCTabBarView. */
@interface MDCTabBarViewTypicalExampleViewControllerCustomView
    : UIView <MDCTabBarViewIndicatorSupporting>
/** A switch shown in the view. */
@property(nonatomic, strong) UISwitch *aSwitch;
@end

@implementation MDCTabBarViewTypicalExampleViewControllerCustomView

- (CGRect)contentFrame {
  return CGRectStandardize(self.aSwitch.frame);
}

- (UISwitch *)aSwitch {
  if (!_aSwitch) {
    _aSwitch = [[UISwitch alloc] init];
    [self addSubview:_aSwitch];
  }
  return _aSwitch;
}

- (void)layoutSubviews {
  [super layoutSubviews];
  self.aSwitch.center = CGPointMake(CGRectGetMidX(self.bounds), CGRectGetMidY(self.bounds));
}

- (CGSize)intrinsicContentSize {
  return self.aSwitch.intrinsicContentSize;
}

- (CGSize)sizeThatFits:(CGSize)size {
  return [self.aSwitch sizeThatFits:size];
}

@end

/**
 Typical use example showing how to place an @c MDCTabBarView within another view.
 */
@interface MDCTabBarViewTypicalExampleViewController : UIViewController <MDCTabBarViewDelegate>

/** The tab bar for this example. */
@property(nonatomic, strong) MDCTabBarView *tabBar;

/** The container scheme injected into this example. */
@property(nonatomic, strong) id<MDCContainerScheming> containerScheme;

@end

@implementation MDCTabBarViewTypicalExampleViewController

- (void)viewDidLoad {
  [super viewDidLoad];
  self.title = kExampleTitle;

  if (!self.containerScheme) {
    self.containerScheme = [[MDCContainerScheme alloc] init];
  }

  self.view.backgroundColor = self.containerScheme.colorScheme.backgroundColor;

  UITabBarItem *item1 = [[UITabBarItem alloc]
      initWithTitle:@"Home"
              image:[[UIImage imageNamed:@"Home"]
                        imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]
                tag:0];
  UITabBarItem *item2 = [[UITabBarItem alloc]
      initWithTitle:@"Unselectable"
              image:[[UIImage imageNamed:@"Favorite"]
                        imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]
                tag:1];
  item2.accessibilityTraits = UIAccessibilityTraitStaticText;
  UITabBarItem *item3 = [[UITabBarItem alloc]
      initWithTitle:@"Cake"
              image:[[UIImage imageNamed:@"Cake"]
                        imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]
                tag:2];
  UITabBarItem *item4 = [[UITabBarItem alloc]
      initWithTitle:@"Email"
              image:[[UIImage imageNamed:@"Email"]
                        imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]
                tag:3];
  UITabBarItem *item5 = [[UITabBarItem alloc]
      initWithTitle:@"Search"
              image:[[UIImage imageNamed:@"Search"]
                        imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]
                tag:4];
  MDCTabBarItem *item6 = [[MDCTabBarItem alloc] initWithTitle:@"A switch" image:nil tag:5];
  MDCTabBarViewTypicalExampleViewControllerCustomView *switchView =
      [[MDCTabBarViewTypicalExampleViewControllerCustomView alloc] init];
  item6.mdc_customView = switchView;
  switchView.aSwitch.onTintColor = self.containerScheme.colorScheme.primaryColor;

  self.tabBar = [[MDCTabBarView alloc] init];
  self.tabBar.tabBarDelegate = self;
  self.tabBar.items = @[ item1, item2, item3, item4, item5, item6 ];
  self.tabBar.barTintColor = self.containerScheme.colorScheme.secondaryColor;
  [self.tabBar setTitleColor:self.containerScheme.colorScheme.onSecondaryColor
                    forState:UIControlStateNormal];
  [self.tabBar setTitleColor:self.containerScheme.colorScheme.primaryColor
                    forState:UIControlStateSelected];
  [self.tabBar setImageTintColor:self.containerScheme.colorScheme.onSecondaryColor
                        forState:UIControlStateNormal];
  [self.tabBar setImageTintColor:self.containerScheme.colorScheme.primaryColor
                        forState:UIControlStateSelected];
  [self.tabBar setTitleFont:self.containerScheme.typographyScheme.button
                   forState:UIControlStateNormal];
  [self.tabBar setTitleFont:[UIFont systemFontOfSize:16] forState:UIControlStateSelected];
  self.tabBar.selectedItem = item4;
  self.tabBar.translatesAutoresizingMaskIntoConstraints = NO;
  [self.view addSubview:self.tabBar];

  if (@available(iOS 11.0, *)) {
    [self.view.layoutMarginsGuide.topAnchor constraintEqualToAnchor:self.tabBar.topAnchor].active =
        YES;
  } else {
    [self.topLayoutGuide.bottomAnchor constraintEqualToAnchor:self.tabBar.topAnchor].active = YES;
  }
  [self.view.leftAnchor constraintEqualToAnchor:self.tabBar.leftAnchor].active = YES;
  [self.view.rightAnchor constraintEqualToAnchor:self.tabBar.rightAnchor].active = YES;
}

#pragma mark - MDCTabBarViewDelegate

- (BOOL)tabBarView:(MDCTabBarView *)tabBarView shouldSelectItem:(nonnull UITabBarItem *)item {
  // Just to demonstrate preventing selection of an item.
  return [self.tabBar.items indexOfObject:item] != 1;
}

- (void)tabBarView:(MDCTabBarView *)tabBarView didSelectItem:(nonnull UITabBarItem *)item {
  NSLog(@"Item (%@) was selected.", item.title);
}

@end

#pragma mark - CatalogByConvention
@implementation MDCTabBarViewTypicalExampleViewController (CatalogByConvention)

+ (NSDictionary *)catalogMetadata {
  return @{
    @"breadcrumbs" : @[ @"Tab Bar", kExampleTitle ],
    @"primaryDemo" : @NO,
    @"presentable" : @NO,
  };
}

@end