Objective c 在单个Uitabritem上处理长按
我在选项卡栏上使用长按手势。但我只需要长按一个特定的选项卡栏项目的手势Objective c 在单个Uitabritem上处理长按,objective-c,uigesturerecognizer,uitabbar,uilongpressgesturerecogni,Objective C,Uigesturerecognizer,Uitabbar,Uilongpressgesturerecogni,我在选项卡栏上使用长按手势。但我只需要长按一个特定的选项卡栏项目的手势 我怎样才能解决这个问题?我可以自定义选项卡栏中的长按手势吗?您可以子类化UIAbbarController,并在其选项卡栏中添加UILongPressGestureRecognitor。作为手势识别器的代表,当它检测到长按时,您可以选择。由于选项卡栏项目将在用户触摸后立即被选中,因此可以使用selectedItem属性执行此检查 @interface TabBarController () <UIGestureReco
我怎样才能解决这个问题?我可以自定义选项卡栏中的长按手势吗?您可以子类化
UIAbbarController
,并在其选项卡栏中添加UILongPressGestureRecognitor
。作为手势识别器的代表,当它检测到长按时,您可以选择。由于选项卡栏项目将在用户触摸后立即被选中,因此可以使用selectedItem
属性执行此检查
@interface TabBarController () <UIGestureRecognizerDelegate>
@property (nonatomic, strong) UILongPressGestureRecognizer *longPressRecognizer;
@end
@implementation TabBarController
- (void)viewDidLoad {
[super viewDidLoad];
self.longPressRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(recognizerFired:)];
self.longPressRecognizer.delegate = self;
[self.tabBar addGestureRecognizer:self.longPressRecognizer];
}
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
// This will ensure the long press only occurs for the
// tab bar item which has it's tag set to 1.
// You can set this in Interface Builder or in code
// wherever you are creating your tabs.
if (self.tabBar.selectedItem.tag == 1) {
return YES;
}
else {
return NO;
}
}
- (void)recognizerFired:(UILongPressGestureRecognizer *)recognizer {
// Handle the long press...
}
@end
@接口选项卡控制器()
@属性(非原子,强)UILongPressGestureRecognitor*LongPressRecognitor;
@结束
@TabBarController的实现
-(无效)viewDidLoad{
[超级视图下载];
self.longPressRecognizer=[[uilongpressgesturecognizer alloc]initWithTarget:self-action:@selector(recognizerfiled:)];
self.longpress recognizer.delegate=self;
[self.tabBar addgesturecognizer:self.longPressRecognizer];
}
-(BOOL)手势识别器应开始:(UIGestureRecognizer*)手势识别器{
//这将确保长时间按压仅发生在
//标签设置为1的选项卡栏项。
//您可以在Interface Builder或代码中进行设置
//无论您在何处创建选项卡。
if(self.tabBar.selectedItem.tag==1){
返回YES;
}
否则{
返回否;
}
}
-(void)识别器已激发:(uiLongPressGestureRecognitor*)识别器{
//处理长时间的压力。。。
}
@结束
如果您只需要识别其中一个选项卡项上的长按,可以在相应的viewController的viewDidLoad
方法中执行此操作:
UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget: self action: @selector(handleLongPress:)];
[self.tabBarController.tabBar addGestureRecognizer: longPressGesture];
然后:
- (void)handleLongPress:(UILongPressGestureRecognizer *) recognizer {
if (recognizer.state == UIGestureRecognizerStateBegan) {
UITabBar *tabBar = ((UITabBar* )recognizer.view);
if (tabBar.selectedItem == self.tabBarItem) {
doSomethingVeryExciting();
}
}
}
如果您只是切换选项卡,则不会触发此操作。以下是我使用Swift 3的方法:
protocol MyTabControllerProtocol: class {
func tabLongPressed()
}
class MyTabController: UITabBarController {
func viewDidLoad() {
super.viewDidLoad()
viewControllers = [
// add your view controllers for each tab bar item
// NOTE: if you want view controller to respond to long press, then it should extend MyTabControllerProtocol
]
let longPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(astroButtonItemLongPressed(_:)))
tabBar.addGestureRecognizer(longPressRecognizer)
}
func astroButtonItemLongPressed(_ recognizer: UILongPressGestureRecognizer) {
guard recognizer.state == .began else { return }
guard let tabBar = recognizer.view as? UITabBar else { return }
guard let tabBarItems = tabBar.items else { return }
guard let viewControllers = viewControllers else { return }
guard tabBarItems.count == viewControllers.count else { return }
let loc = recognizer.location(in: tabBar)
for (index, item) in tabBarItems.enumerated() {
guard let view = item.value(forKey: "view") as? UIView else { continue }
guard view.frame.contains(loc) else { continue }
if let nc = viewControllers[index] as? UINavigationController {
if let vc = nc.viewControllers.first as? MyTabControllerProtocol {
vc.tabLongPressed()
}
} else if let vc = viewControllers[index] as? MyTabControllerProtocol {
vc.tabLongPressed()
}
break
}
}
}
我通过获取特定tabBarItem的用户可以交互的视图来实现这一点,并简单地添加了长按手势。通过这种方式,您不必编写任何协议或TabBarViewController的子类
let longPressGestureRecognizer = UILongPressGestureRecognizer.init(target: self, action: #selector(longTap(_:)))
longPressGestureRecognizer.minimumPressDuration = 1.0
self.tabBarController?.orderedTabBarItemViews()[0].addGestureRecognizer(longPressGestureRecognizer)
至于获取tabbarItemView:
extension UITabBarController {
func orderedTabBarItemViews() -> [UIView] {
let interactionViews = tabBar.subviews.filter({$0.isUserInteractionEnabled})
return interactionViews.sorted(by: {$0.frame.minX < $1.frame.minX})
}
扩展控制器{
func orderedTabBarItemViews()->[UIView]{
让interactionViews=tabBar.subviews.filter({$0.isUserInteractionEnabled})
返回interactionViews.sorted(按:{$0.frame.minX<$1.frame.minX})
}
备注:viewController,即“self”是tabBarController的第一项。以下是swift 5中的解决方案:
使用情节提要或代码将longpress手势识别器添加到“整个”选项卡栏。。
别忘了让ViewController成为它的委托..并实现下面的委托方法
要检查传入的触摸是否在选项卡栏子视图的“一”内,请执行以下操作。如果是,则返回true,否则返回false。。
以下是仅当我们长按第一个选项卡时才允许识别器启动的代码:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
if touch.view?.isDescendant(of: tabBar.subviews[1]) == true {return true}
return false
}
注意:tabbar.subviews数组计数是项目数+1,这是tabbar的背景。所以,若您想查看第一个项目,您可以找到它,索引1而不是0请共享您的代码或IB。我的代码不正确。是否可以识别长按TabBarItem而不切换tab?若用户选择firs怎么办t item然后点击并按住任何其他项目,它仍然可以工作,这并不酷。因为第一个项目仍然会被选中!@AkhilKC从UITabBarControllerDelegate
查看shoulldselect
方法谢谢,这是最好的答案。