在TableView上添加悬浮按钮

  如果直接在TableVIewController上贴Button的话会导致这个会随之滚动,下面解决在TableView上实现位置固定悬浮按钮的两种方法:

  1.在view上贴tableView,然后将悬浮按钮贴在view的最顶层

  2.使用window

首先看一下最终的效果,在tableViewController上添加一个悬浮按钮,该按钮不能随着视图的滚动而滚动

   在TableView上添加悬浮按钮

首先介绍上面的第一种方法:

1)创建tableview和底部按钮的属性

//屏幕宽

#define kScreenW [UIScreen mainScreen].bounds.size.width

//屏幕高

#define kScreenH [UIScreen mainScreen].bounds.size.height

@interface broadcastLiveViewController ()<UITableViewDataSource, UITableViewDelegate>

@property(nonatomic) UITableView *livesListTable;

@property(nonatomic) UIButton *bottomButton;

@end

2)创建属性到最顶部

@implementation broadcastLiveViewController

- (void)viewDidLoad {

[super viewDidLoad];

  CGRect clientRect = [UIScreen mainScreen].bounds;

  _livesListTable = [[UITableView alloc] initWithFrame:CGRectMake(0, 0, clientRect.size.width, clientRect.size.height-65) style:UITableViewStylePlain];

[self.view addSubview:_livesListTable];

_livesListTable.delegate = self;

_livesListTable.dataSource = self;

 self.bottomButton = [UIButton buttonWithType:UIButtonTypeCustom];

self.bottomButton.frame = CGRectMake(kScreenW - 80, kScreenH - 140, 60, 60);

[self.bottomButton setBackgroundImage:[UIImage imageNamed:@"recordLive"] forState:UIControlStateNormal];

[self.bottomButton addTarget:self action:@selector(onTapLiveBtn) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:self.bottomButton];

3)实现按钮事件

- (void)onTapLiveBtn

{

NSLog(@"点击底部按钮");

}

接下来介绍第二种方法:

1)创建一个window,button属性避免window被释放

//屏幕宽

#define kScreenW [UIScreen mainScreen].bounds.size.width

//屏幕高

#define kScreenH [UIScreen mainScreen].bounds.size.height

@interface broadcastLiveViewController ()<UITableViewDataSource, UITableViewDelegate>

@property(strong,nonatomic)UIWindow *window;

@property(strong,nonatomic)UIButton *button;

@end

2)创建window和button

默认的情况下系统只有一个window这时我们需要设置windowLevel

window不用添加在任何视图上

- (void)createButton{

    _button = [UIButton buttonWithType:UIButtonTypeCustom];
 [_button setBackgroundImage:[UIImage imageNamed:@"recordLive"] forState:UIControlStateNormal];
_button.frame = CGRectMake(0, 0, 60, 60);
[_button addTarget:self action:@selector(onTapLiveBtn) forControlEvents:UIControlEventTouchUpInside];
_window = [[UIWindow alloc]initWithFrame: CGRectMake(kScreenW - 80, kScreenH - 80, 60, 60);];
_window.windowLevel = UIWindowLevelAlert+1;
_window.backgroundColor = [UIColor redColor];
_window.layer.cornerRadius = 30;
_window.layer.masksToBounds = YES;
[_window addSubview:_button];
[_window makeKeyAndVisible];//关键语句,显示window
} 3)延时加载window,注意我们需要在rootWindow创建完成之后再创建这个悬浮的按钮
- (void)viewDidLoad {
[super viewDidLoad];
[self performSelector:@selector(createButton) withObject:nil afterDelay:1];
}
4)实现按钮事件

- (void)onTapLiveBtn

{

NSLog(@"点击底部按钮");

}


注意::最后再添加一个小功能,使tableview上下滑动的时候,按钮动画效果的出现和消失,在这里是上拉消失,下拽出现

-(void)scrollViewDidScroll:(UIScrollView *)scrollView{

if (scrollView.contentOffset.y > self.offsetY && scrollView.contentOffset.y > 0) {//向上滑动

//按钮消失

[UIView transitionWithView:self.bottomButton duration:0.1 options:UIViewAnimationOptionTransitionNone animations:^{

self.bottomButton.frame = CGRectMake(kScreenW - 80, kScreenH - 65, 60, 60);

} completion:NULL]; 

}else if (scrollView.contentOffset.y < self.offsetY ){//向下滑动

//按钮出现

[UIView transitionWithView:self.bottomButton duration:0.1 options:UIViewAnimationOptionTransitionNone animations:^{

self.bottomButton.frame = CGRectMake(kScreenW - 80, kScreenH - 140, 60, 60);

} completion:NULL];

}

self.offsetY = scrollView.contentOffset.y;//将当前位移变成缓存位移

}

 
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