首页 / 移动开发 / IOS / iOS实现简单的二级菜单效果

示例代码如下

Untitled.gif#import "ViewController.h"#import "CollectionViewCell.h"#import "CollectionSectionView.h"@interface ViewController （）<UICollectionViewDelegateFlowLayout,UICollectionViewDataSource>@property （nonatomic,strong）UICollectionView *collectionView;@property （nonatomic,copy）NSString *leftOrRight;@property （nonatomic,strong）NSIndexPath *clickIndexPath;@endstatic NSString *cellIdentifier = @"CollectionViewCell";static NSString *sectionIdentifier = @"CollectionSectionView";@implementation ViewController- （void）viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init]; flowLayout.itemSize = CGSizeMake（50, 25）; flowLayout.minimumLineSpacing = 0; flowLayout.minimumInteritemSpacing = 0; flowLayout.headerReferenceSize = CGSizeMake（0, 40）; flowLayout.sectionInset = UIEdgeInsetsMake（0, 0, 0, 0）; self.collectionView = [[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:flowLayout]; _collectionView.backgroundColor = [UIColor whiteColor]; _collectionView.delegate = self; _collectionView.dataSource = self; [_collectionView registerClass:[CollectionViewCell class] forCellWithReuseIdentifier:cellIdentifier]; [_collectionView registerClass:[CollectionSectionView class] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:sectionIdentifier]; [self.view addSubview:_collectionView];}- （NSInteger）numberOfSectionsInCollectionView:（UICollectionView *）collectionView{ return 3;}- （NSInteger）collectionView:（UICollectionView *）collectionView numberOfItemsInSection:（NSInteger）section{ if （self.clickIndexPath.section == section） {if （self.clickIndexPath.section == 0 && [self.leftOrRight isEqualToString:@"left"]） { return 3;}if （self.clickIndexPath.section == 0 && [self.leftOrRight isEqualToString:@"right"]） { return 4;}if （self.clickIndexPath.section == 1 && [self.leftOrRight isEqualToString:@"left"]） { return 10;}if （self.clickIndexPath.section == 1 && [self.leftOrRight isEqualToString:@"right"]） { return 8;}if （self.clickIndexPath.section == 2 && [self.leftOrRight isEqualToString:@"left"]） { return 33;}if （self.clickIndexPath.section == 2 && [self.leftOrRight isEqualToString:@"right"]） { return 6;} } return 0;}- （UICollectionViewCell *）collectionView:（UICollectionView *）collectionView cellForItemAtIndexPath:（NSIndexPath *）indexPath{ CollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath]; cell.label.text = [NSString stringWithFormat:@"%ld-%ld",indexPath.section,indexPath.row]; return cell;}- （UICollectionReusableView *）collectionView:（UICollectionView *）collectionView viewForSupplementaryElementOfKind:（NSString *）kind atIndexPath:（NSIndexPath *）indexPath{ if （[kind isEqualToString:UICollectionElementKindSectionHeader]） {CollectionSectionView *sectionView = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:sectionIdentifier forIndexPath:indexPath];sectionView.backgroundColor = [UIColor lightGrayColor];sectionView.leftStr = @"家具";sectionView.rightStr = @"家电";[sectionView customBtnHandelAction:^（NSString *leftOrRight） { self.clickIndexPath = indexPath; self.leftOrRight = leftOrRight; [collectionView reloadData];}];return sectionView; } return nil;}- （void）didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated.}

#import <UIKit/UIKit.h>typedef void（^BtnHandleAction）（NSString *leftOrRight）;@interface CollectionSectionView : UICollectionReusableView@property （nonatomic,copy）NSString *leftStr;@property （nonatomic,copy）NSString *rightStr;- （void）customBtnHandelAction:（BtnHandleAction）action;@end

#import "CollectionSectionView.h"@interface CollectionSectionView （）@property （nonatomic,strong）UIButton *leftBtn;@property （nonatomic,strong）UIButton *rightBtn;@property （nonatomic,copy）BtnHandleAction btnHandelAction;@end@implementation CollectionSectionView- （instancetype）initWithFrame:（CGRect）frame{ self = [super initWithFrame:frame]; if （self） {[self setup]; } return self;}- （UIButton *）leftBtn{ if （！_leftBtn） {self.leftBtn = [UIButton buttonWithType:（UIButtonTypeCustom）];_leftBtn.tag = 2000;_leftBtn.frame = CGRectMake（1, 1, self.frame.size.width / 2 - 2, self.frame.size.height - 2）;_leftBtn.backgroundColor = [UIColor whiteColor];[_leftBtn addTarget:self action:@selector（btnAction:） forControlEvents:（UIControlEventTouchUpInside）]; } return _leftBtn;}- （UIButton *）rightBtn{ if （！_rightBtn） {self.rightBtn = [UIButton buttonWithType:（UIButtonTypeCustom）];_rightBtn.tag = 2001;_rightBtn.frame = CGRectMake（self.frame.size.width / 2 + 1, 1, self.frame.size.width / 2 - 2, self.frame.size.height - 2）;_rightBtn.backgroundColor = [UIColor whiteColor];[_rightBtn addTarget:self action:@selector（btnAction:） forControlEvents:（UIControlEventTouchUpInside）]; } return _rightBtn;}- （void）btnAction:（UIButton *）sender{ NSInteger tag = sender.tag; if （tag == 2000） {self.btnHandelAction（@"left"）; } if （tag == 2001） {self.btnHandelAction（@"right"）; }}- （void）customBtnHandelAction:（BtnHandleAction）action{ self.btnHandelAction = action;}- （void）setup{ [self addSubview:self.leftBtn]; [self addSubview:self.rightBtn];}- （void）setLeftStr:（NSString *）leftStr{ [self.leftBtn setTitle:leftStr forState:（UIControlStateNormal）]; [self.leftBtn setTitleColor:[UIColor blackColor] forState:（UIControlStateNormal）];}- （void）setRightStr:（NSString *）rightStr{ [self.rightBtn setTitle:rightStr forState:（UIControlStateNormal）]; [self.rightBtn setTitleColor:[UIColor blackColor] forState:（UIControlStateNormal）];}@end