material-components_material-components-ios/components/Tabs/examples/TabBarInterfaceBuilderExample.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 <UIKit/UIKit.h>

#import "MaterialColorScheme.h"
#import "MaterialPalettes.h"
#import "MaterialTabs.h"
#import "MaterialTabs+ColorThemer.h"

@interface TabBarInterfaceBuilderExample : UIViewController <MDCTabBarDelegate>

@property(weak, nonatomic) IBOutlet MDCTabBar *tabBar;
@property(nonatomic) NSArray<UIColor *> *colors;
@property(nonatomic, strong) MDCSemanticColorScheme *colorScheme;

@end

@implementation TabBarInterfaceBuilderExample

- (id)init {
  self = [super init];
  if (self) {
    self.colorScheme = [[MDCSemanticColorScheme alloc] init];
  }
  return self;
}

- (void)viewDidLoad {
  [super viewDidLoad];

  self.tabBar.items = @[
    [[UITabBarItem alloc] initWithTitle:@"Blue" image:nil tag:0],
    [[UITabBarItem alloc] initWithTitle:@"Pink" image:nil tag:1],
    [[UITabBarItem alloc] initWithTitle:@"Red" image:nil tag:2],
    [[UITabBarItem alloc] initWithTitle:@"Green" image:nil tag:3]
  ];

  self.colors = @[
    MDCPalette.bluePalette.tint500, MDCPalette.pinkPalette.tint500,
    MDCPalette.redPalette.tint500, MDCPalette.greenPalette.tint500
  ];

  [MDCTabBarColorThemer applySemanticColorScheme:self.colorScheme toTabs:self.tabBar];
  
  self.view.backgroundColor = self.colors[0];
}

#pragma mark MDCTabBarDelegate

- (void)tabBar:(MDCTabBar *)tabBar didSelectItem:(UITabBarItem *)item {
  self.view.backgroundColor = self.colors[item.tag];
}

#pragma mark Target / Action

- (IBAction)alignmentButtonDidTouch:(UIButton *)sender {
  UIAlertController *sheet =
      [UIAlertController alertControllerWithTitle:nil
                                          message:nil
                                   preferredStyle:UIAlertControllerStyleActionSheet];
  sheet.popoverPresentationController.sourceView = sender;
  sheet.popoverPresentationController.sourceRect = sender.bounds;
  [sheet addAction:[UIAlertAction actionWithTitle:@"Leading"
                                            style:UIAlertActionStyleDefault
                                          handler:^(UIAlertAction *_Nonnull action) {
                                            [self.tabBar setAlignment:MDCTabBarAlignmentLeading];
                                          }]];
  [sheet addAction:[UIAlertAction actionWithTitle:@"Center"
                                            style:UIAlertActionStyleDefault
                                          handler:^(UIAlertAction *_Nonnull action) {
                                            [self.tabBar setAlignment:MDCTabBarAlignmentCenter];
                                          }]];
  [sheet addAction:[UIAlertAction actionWithTitle:@"Justified"
                                            style:UIAlertActionStyleDefault
                                          handler:^(UIAlertAction *_Nonnull action) {
                                            [self.tabBar setAlignment:MDCTabBarAlignmentJustified];
                                          }]];
  [sheet addAction:[UIAlertAction actionWithTitle:@"Selected Center"
                                            style:UIAlertActionStyleDefault
                                          handler:^(UIAlertAction *_Nonnull action) {
                                            [self.tabBar
                                                setAlignment:MDCTabBarAlignmentCenterSelected];
                                          }]];
  [self presentViewController:sheet animated:YES completion:nil];
}

@end

@implementation TabBarInterfaceBuilderExample (Supplemental)

- (UIStatusBarStyle)preferredStatusBarStyle {
  // Ensure that our status bar is white.
  return UIStatusBarStyleLightContent;
}

@end

@implementation TabBarInterfaceBuilderExample (CatalogByConvention)

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

@end