长按uitableview
-
29-09-2019 - |
题
我想在一个上处理长期按 UITableViewCell
打印“快速访问菜单”。有人已经这样做了吗?
特别是手势认识 UITableView
?
解决方案
首先将长按手势识别器添加到表视图中:
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 2.0; //seconds
lpgr.delegate = self;
[self.myTableView addGestureRecognizer:lpgr];
[lpgr release];
然后在手势处理程序中:
-(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
{
CGPoint p = [gestureRecognizer locationInView:self.myTableView];
NSIndexPath *indexPath = [self.myTableView indexPathForRowAtPoint:p];
if (indexPath == nil) {
NSLog(@"long press on table view but not on a row");
} else if (gestureRecognizer.state == UIGestureRecognizerStateBegan) {
NSLog(@"long press on table view at row %ld", indexPath.row);
} else {
NSLog(@"gestureRecognizer.state = %ld", gestureRecognizer.state);
}
}
您必须小心这样 handleLongPress
可能会多次开火(这是由于手势识别器状态的变化引起的)。
其他提示
我已经使用了Anna-Karenina的答案,并且在一个非常严重的错误中效果很好。
如果您正在使用各节,则长期按照部分标题将为您按下该部分上的第一行提供错误的结果,我在下面添加了一个固定的版本(包括基于手势状态的虚拟呼叫的过滤, Anna-Karenina建议)。
- (IBAction)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
{
if (gestureRecognizer.state == UIGestureRecognizerStateBegan) {
CGPoint p = [gestureRecognizer locationInView:self.tableView];
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:p];
if (indexPath == nil) {
NSLog(@"long press on table view but not on a row");
} else {
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
if (cell.isHighlighted) {
NSLog(@"long press on table view at section %d row %d", indexPath.section, indexPath.row);
}
}
}
}
这是结合Dawn Song的答案和Marmor的答案的澄清说明。
拖动长按手势识别器,然后将其放入您的表单元格中。它将跳到左侧列表的底部。
在动作处理程序中添加Marmor的代码
- (IBAction)handleLongPress:(UILongPressGestureRecognizer *)sender {
if (sender.state == UIGestureRecognizerStateBegan) {
CGPoint p = [sender locationInView:self.tableView];
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:p];
if (indexPath == nil) {
NSLog(@"long press on table view but not on a row");
} else {
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
if (cell.isHighlighted) {
NSLog(@"long press on table view at section %d row %d", indexPath.section, indexPath.row);
}
}
}
}
在Swift 5中的答案(Ricky在Swift中的回答延续)
添加
UIGestureRecognizerDelegate
向您的ViewController
override func viewDidLoad() {
super.viewDidLoad()
//Long Press
let longPressGesture = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress))
longPressGesture.minimumPressDuration = 0.5
longPressGesture.delegate = self
self.tableView.addGestureRecognizer(longPressGesture)
}
和功能:
@objc func handleLongPress(longPressGesture: UILongPressGestureRecognizer) {
let p = longPressGesture.location(in: self.tableView)
let indexPath = self.tableView.indexPathForRow(at: p)
if indexPath == nil {
print("Long press on table view, not row.")
} else if longPressGesture.state == UIGestureRecognizer.State.began {
print("Long press on row, at \(indexPath!.row)")
}
}
在Swift中回答:
添加委托 UIGestureRecognizerDelegate
到您的uitaiteViewController。
在uitaiteViewController中:
override func viewDidLoad() {
super.viewDidLoad()
let longPressGesture:UILongPressGestureRecognizer = UILongPressGestureRecognizer(target: self, action: "handleLongPress:")
longPressGesture.minimumPressDuration = 1.0 // 1 second press
longPressGesture.delegate = self
self.tableView.addGestureRecognizer(longPressGesture)
}
和功能:
func handleLongPress(longPressGesture:UILongPressGestureRecognizer) {
let p = longPressGesture.locationInView(self.tableView)
let indexPath = self.tableView.indexPathForRowAtPoint(p)
if indexPath == nil {
print("Long press on table view, not row.")
}
else if (longPressGesture.state == UIGestureRecognizerState.Began) {
print("Long press on row, at \(indexPath!.row)")
}
}
我根据安娜·卡雷纳娜(Anna Karenina)的出色答案,在UitaiteView上汇总了一个小类。
像这样,您将拥有一种方便的委托方法,就像您在处理常规表视图时习惯一样。看看这个:
// UITableView+LongPress.h
#import <UIKit/UIKit.h>
@protocol UITableViewDelegateLongPress;
@interface UITableView (LongPress) <UIGestureRecognizerDelegate>
@property(nonatomic,assign) id <UITableViewDelegateLongPress> delegate;
- (void)addLongPressRecognizer;
@end
@protocol UITableViewDelegateLongPress <UITableViewDelegate>
- (void)tableView:(UITableView *)tableView didRecognizeLongPressOnRowAtIndexPath:(NSIndexPath *)indexPath;
@end
// UITableView+LongPress.m
#import "UITableView+LongPress.h"
@implementation UITableView (LongPress)
@dynamic delegate;
- (void)addLongPressRecognizer {
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 1.2; //seconds
lpgr.delegate = self;
[self addGestureRecognizer:lpgr];
}
- (void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
{
CGPoint p = [gestureRecognizer locationInView:self];
NSIndexPath *indexPath = [self indexPathForRowAtPoint:p];
if (indexPath == nil) {
NSLog(@"long press on table view but not on a row");
}
else {
if (gestureRecognizer.state == UIGestureRecognizerStateBegan) {
// I am not sure why I need to cast here. But it seems to be alright.
[(id<UITableViewDelegateLongPress>)self.delegate tableView:self didRecognizeLongPressOnRowAtIndexPath:indexPath];
}
}
}
如果您想在uitaiteViewController中使用它,则可能需要子类并符合新协议。
它对我来说很好,希望它能帮助别人!
Swift 3答案,使用现代语法,结合了其他答案,并消除了不需要的代码。
override func viewDidLoad() {
super.viewDidLoad()
let recognizer = UILongPressGestureRecognizer(target: self, action: #selector(tablePressed))
tableView.addGestureRecognizer(recognizer)
}
@IBAction func tablePressed(_ recognizer: UILongPressGestureRecognizer) {
let point = recognizer.location(in: tableView)
guard recognizer.state == .began,
let indexPath = tableView.indexPathForRow(at: point),
let cell = tableView.cellForRow(at: indexPath),
cell.isHighlighted
else {
return
}
// TODO
}
只需将UilongPressestureRecognizer添加到故事板中给定的原型单元格中,然后将手势拉到ViewController的.m文件中以创建一个动作方法。我像我说的那样做到了。
使用touchesbegan中的Uitouch Timestamp属性启动计时器或在触摸被解雇时停止该计时器