二、iOS常用控件
UICollectionView
1、声明属性
@property (nonatomic, strong) UICollectionView *collectionView;
@property (nonatomic, strong) NSArray *dataSource;
2、遵守协议
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
return self.dataSource.count;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(nonnull NSIndexPath *)indexPath {
LCCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"LCCell" forIndexPath:indexPath];
return cell;
}
- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {
if ([kind isEqualToString:UICollectionElementKindSectionHeader]) {
LCHHeader *header = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"LCHHeader" forIndexPath:indexPath];
return header;
} else {
LCFooter *footer = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionFooter withReuseIdentifier:@"LCFooter" forIndexPath:indexPath];
return footer;
}
}
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
LCCell *cell = (LCCell *)[collectionView cellForItemAtIndexPath:indexPath];
// TUDO:
}
3、getter方法
- (UICollectionView *)collectionView {
if (_collectionView == nil) {
CGFloat space = 1;
UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
layout.scrollDirection = UICollectionViewScrollDirectionVertical;
layout.minimumLineSpacing = space;
layout.minimumInteritemSpacing = space;
layout.sectionInset = UIEdgeInsetsMake(space, space, space, space);
CGFloat width = self.view.bounds.size.width;
layout.headerReferenceSize = CGSizeMake(width, width * 200 / 320);
layout.footerReferenceSize = CGSizeMake(width, 40);
CGFloat itemWidth = (width - layout.sectionInset.left - layout.sectionInset.right - space * (4 - 1)) / 4;
layout.itemSize = CGSizeMake(itemWidth, itemWidth);
_collectionView = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
_collectionView.backgroundColor = [UIColor whiteColor];
_collectionView.delegate = self;
_collectionView.dataSource = self;
_collectionView.showsVerticalScrollIndicator = NO;
_collectionView.showsHorizontalScrollIndicator = NO;
[self.view addSubview:_collectionView];
[_collectionView mas_makeConstraints:^(MASConstraintMaker *make) {
make.left.right.top.bottom.equalTo(self.view);
}];
[_collectionView registerClass:[LCCell class]
forCellWithReuseIdentifier:@"LCCell"];
[_collectionView registerClass:[LCHeader class]
forSupplementaryViewOfKind:UICollectionElementKindSectionHeader
withReuseIdentifier:@"LCHeader"];
[_collectionView registerClass:[LCFooter class]
forSupplementaryViewOfKind:UICollectionElementKindSectionFooter
withReuseIdentifier:@"LCFooter"];
}
return _collectionView;
}
- (NSArray *)dataSource {
if (_dataSource == nil) {
_dataSource = @[];
}
return _dataSource;
}
UITableView
1、声明属性
@property (nonatomic, strong) UITableView *tableView;
2、遵守协议
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return 2;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"XXXCell"];
if (!cell) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"XXXCell"];
}
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// TUDO:
}
3、getter方法
- (UITableView *)tableView {
if (_tableView == nil) {
_tableView = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStylePlain];
_tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
_tableView.dataSource = self;
_tableView.delegate = self;
_tableView.rowHeight = 60;
[self.view addSubview:_tableView];
[_tableView mas_makeConstraints:^(MASConstraintMaker *make) {
make.left.right.top.bottom.equalTo(self.view);
}];
}
return _tableView;
}
手势
添加手势
// 左滑
UISwipeGestureRecognizer *leftSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
leftSwipe.direction = UISwipeGestureRecognizerDirectionLeft;
[self.view addGestureRecognizer:leftSwipe];
// 右滑
UISwipeGestureRecognizer *rightSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
rightSwipe.direction = UISwipeGestureRecognizerDirectionRight;
[self.view addGestureRecognizer:rightSwipe];
// 单击
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
singleTap.numberOfTapsRequired = 1;
[self.view addGestureRecognizer:singleTap];
// 双击
UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
doubleTap.numberOfTapsRequired = 2;
[self.view addGestureRecognizer:doubleTap];
// 拖拽
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
[self.view addGestureRecognizer:pan];
// 缩放
UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
[self.view addGestureRecognizer:pinch];
// 旋转
UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
[self.view addGestureRecognizer:rotation];
// 长按
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(processgestureReconizer:)];
longPress.minimumPressDuration = 2.0;
[self.view addGestureRecognizer:longPress];
部分手势处理
- (void)processgestureReconizer:(UIGestureRecognizer *)gesture {
// 拖拽
if ([gesture isKindOfClass:[UIPanGestureRecognizer class]]) {
// UIPanGestureRecognizer *pan = (UIPanGestureRecognizer *)gesture;
// CGPoint point = [pan translationInView:pan.view];
// pan.view.transform = CGAffineTransformTranslate(pan.view.transform, point.x, point.y);
// [pan setTranslation:CGPointZero inView:pan.view];
UIPanGestureRecognizer *pan = (UIPanGestureRecognizer *)gesture;
CGPoint startCenter = CGPointZero;
if (pan.state == UIGestureRecognizerStateBegan) {
startCenter = gesture.view.center;
} else if (pan.state == UIGestureRecognizerStateChanged) {
// 此处必须从self.view中获取translation，因为translation和view的transform属性挂钩，若transform改变了则translation也会变
CGPoint translation = [pan translationInView:self.view];
gesture.view.center = CGPointMake(startCenter.x + translation.x, startCenter.y + translation.y);
} else if (pan.state == UIGestureRecognizerStateEnded) {
startCenter = CGPointZero;
}
}
// 缩放
if ([gesture isKindOfClass:[UIPinchGestureRecognizer class]]) {
UIPinchGestureRecognizer *pinch = (UIPinchGestureRecognizer *)gesture;
CGFloat startScale = 1;
if (pinch.state == UIGestureRecognizerStateBegan) {
startScale = pinch.scale;
} else if (pinch.state == UIGestureRecognizerStateChanged) {
CGFloat scale = (pinch.scale - startScale) / 2 + 1;
gesture.view.transform = CGAffineTransformScale(gesture.view.transform, scale, scale);
startScale = pinch.scale;
} else if (pinch.state == UIGestureRecognizerStateEnded) {
startScale = 1;
}
}
// 旋转
if ([gesture isKindOfClass:[UIRotationGestureRecognizer class]]) {
UIRotationGestureRecognizer *rotate = (UIRotationGestureRecognizer *)gesture;
CGFloat startRotation = 0;
if (rotate.state == UIGestureRecognizerStateBegan) {
startRotation = rotate.rotation;
} else if (rotate.state == UIGestureRecognizerStateChanged) {
CGFloat rotation = (rotate.rotation - startRotation) / 2;
gesture.view.transform = CGAffineTransformRotate(gesture.view.transform, rotation);
startRotation = rotate.rotation;
} else if (rotate.state == UIGestureRecognizerStateEnded) {
startRotation = 0;
}
}
}
UITabBarController
// 通过此方法能够让子控制器的 NavigationItem 替换 TabBarController 的 NavigationItem
- (void)setSelectedViewController:(UIViewController *)selectedViewController {
[super setSelectedViewController:selectedViewController];
if (nil != selectedViewController.navigationItem.titleView) {
self.navigationItem.titleView = selectedViewController.navigationItem.titleView;
} else {
self.navigationItem.titleView = nil;
self.navigationItem.title = selectedViewController.navigationItem.title;
}
self.navigationItem.leftBarButtonItem = selectedViewController.navigationItem.leftBarButtonItem;
self.navigationItem.leftBarButtonItems = selectedViewController.navigationItem.leftBarButtonItems;
self.navigationItem.rightBarButtonItem = selectedViewController.navigationItem.rightBarButtonItem;
self.navigationItem.rightBarButtonItems = selectedViewController.navigationItem.rightBarButtonItems;
}
基于GCD的倒计时按钮
// 基于GCD的倒计时按钮
- (void)countdown:(int)maxTime button:(UIButton *)button {
// 关闭按钮的交互
button.userInteractionEnabled = NO;
__block int timeout = (int)maxTime;
__weak typeof(button) weakButton = button;
// 获取全局子线程队列
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
// 创建timer添加到队列中
dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue);
// 设置时间间隔
dispatch_source_set_timer(timer, DISPATCH_TIME_NOW, 1.0 * NSEC_PER_SEC, 0);
// 处理事件block
dispatch_source_set_event_handler(timer, ^{
dispatch_async(dispatch_get_main_queue(), ^{
timeout--;
[weakButton setTitle:timeout > 0 ? [NSString stringWithFormat:@"%d s", timeout] : @"Resend" forState:UIControlStateNormal];
weakButton.userInteractionEnabled = timeout > 0 ? NO : YES;
// 倒计时结束，关闭定时器
if (timeout <= 0) {
dispatch_source_cancel(timer);
}
});
});
// 定时器
dispatch_resume(timer);
}