经过大量的试验和错误,我放弃了,并提出了这个问题。我见过很多人有类似的问题,但不能得到所有的答案工作正确。
我有一个由自定义单元格组成的UITableView。单元格由相邻的5个文本字段组成(有点像网格)。
当我试图滚动和编辑UITableView底部的单元格时,我不能设法让我的单元格正确地定位在键盘上方。
我看到过很多关于改变视图大小的回答……但到目前为止,没有一种效果很好。
谁能用一个具体的代码示例来阐明这样做的“正确”方式?
经过大量的试验和错误,我放弃了,并提出了这个问题。我见过很多人有类似的问题,但不能得到所有的答案工作正确。
我有一个由自定义单元格组成的UITableView。单元格由相邻的5个文本字段组成(有点像网格)。
当我试图滚动和编辑UITableView底部的单元格时,我不能设法让我的单元格正确地定位在键盘上方。
我看到过很多关于改变视图大小的回答……但到目前为止,没有一种效果很好。
谁能用一个具体的代码示例来阐明这样做的“正确”方式?
当前回答
使用UITextField的委托方法:
斯威夫特
func textFieldShouldBeginEditing(textField: UITextField) -> bool {
let txtFieldPosition = textField.convertPoint(textField.bounds.origin, toView: yourTableViewHere)
let indexPath = yourTablViewHere.indexPathForRowAtPoint(txtFieldPosition)
if indexPath != nil {
yourTablViewHere.scrollToRowAtIndexPath(indexPath!, atScrollPosition: .Top, animated: true)
}
return true
}
objective - c
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
CGPoint txtFieldPosition = [textField convertPoint:CGPointZero toView: yourTablViewHere];
NSLog(@"Begin txtFieldPosition : %@",NSStringFromCGPoint(txtFieldPosition));
NSIndexPath *indexPath = [yourTablViewHere indexPathForRowAtPoint:txtFieldPosition];
if (indexPath != nil) {
[yourTablViewHere scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
}
return YES;
}
其他回答
如果你使用UITableViewController而不是UIViewController,它会自动这样做。
在viewdidload
-(void)viewdidload{
[super viewdidload];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChange:) name:UIKeyboardWillChangeFrameNotification object:nil];
}
-(void)keyboardWillChange:(NSNotification*)sender{
NSLog(@"keyboardwillchange sender %@",sender);
float margin=0 // set your own topmargin
CGFloat originY = [[sender.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].origin.y;
if (originY >= self.view.frame.size.height){
NSLog(@"keyboardclose");
[tb_ setFrame:CGRectMake(0, margin, self.view.frame.size.width, self.view.frame.size.height-margin)];
}else{
NSLog(@"keyobard on");
float adjustedHeight = self.view.frame.size.height - margin - (self.view.frame.size.height-originY);
[tb_ setFrame:CGRectMake(0, margin, self.view.frame.size.width, adjustedHeight)];
}
}
Swift 3-4动画和键盘帧改变的解决方案:
首先,创建Bool类型:
// MARK: - Private Properties
private var isKeyboardShowing = false
其次,在系统键盘通知中添加观察者:
// MARK: - Overriding ViewController Life Cycle Methods
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: .UIKeyboardWillHide, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChangeFrame), name: .UIKeyboardWillChangeFrame, object: nil)
}
第三,准备动画功能:
func adjustTableViewInsets(keyboardHeight: CGFloat, duration: NSNumber, curve: NSNumber){
var extraHeight: CGFloat = 0
if keyboardHeight > 0 {
extraHeight = 20
isKeyboardShowing = true
} else {
isKeyboardShowing = false
}
let contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight + extraHeight, right: 0)
func animateFunc() {
//refresh constraints
//self.view.layoutSubviews()
tableView.contentInset = contentInset
}
UIView.animate(withDuration: TimeInterval(duration), delay: 0, options: [UIViewAnimationOptions(rawValue: UInt(curve))], animations: animateFunc, completion: nil)
}
然后添加target/action方法(由观察者调用):
// MARK: - Target/Selector Actions
func keyboardWillShow(notification: NSNotification) {
if !isKeyboardShowing {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
let keyboardHeight = keyboardSize.height
let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber
adjustTableViewInsets(keyboardHeight: keyboardHeight, duration: duration, curve: curve)
}
}
}
func keyboardWillHide(notification: NSNotification) {
let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber
adjustTableViewInsets(keyboardHeight: 0, duration: duration, curve: curve)
}
func keyboardWillChangeFrame(notification: NSNotification) {
if isKeyboardShowing {
let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber
if let newKeyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
let keyboardHeight = newKeyboardSize.height
adjustTableViewInsets(keyboardHeight: keyboardHeight, duration: duration, curve: curve)
}
}
}
最后,不要忘记在deinit或viewWillDisappear中删除观察者:
deinit {
NotificationCenter.default.removeObserver(self)
}
不需要任何计算,使用下面的代码,它将工作: 这段代码我用在我的自定义UITableviewcell,它是工作的:
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)}
func keyboardWillShow(_ notification:Notification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
tableView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0)
}}
func keyboardWillHide(_ notification:Notification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
tableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)
}}
Swift 4.2的小变化…
在我的UITableView上,我有很多部分,但我必须避免浮动标题效果,所以我使用了“dummyViewHeight”方法,就像在Stack Overflow上看到的其他地方一样… 这就是我对这个问题的解决方案(它也适用于键盘+工具栏+建议):
将其声明为类常量:
let dummyViewHeight: CGFloat = 40.0
Then
override func viewDidLoad() {
super.viewDidLoad()
//... some stuff here, not needed for this example
// Create non floating header
tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: tableView.bounds.size.width, height: dummyViewHeight))
tableView.contentInset = UIEdgeInsets(top: -dummyViewHeight, left: 0, bottom: 0, right: 0)
addObservers()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
removeObservers()
}
这里所有的魔法……
@objc func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
let keyboardHeight = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as AnyObject).cgRectValue.size.height
tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: self.tableView.bounds.size.width, height: dummyViewHeight))
tableView.contentInset = UIEdgeInsets(top: -dummyViewHeight, left: 0, bottom: keyboardHeight, right: 0)
}
}
@objc func keyboardWillHide(notification: NSNotification) {
UIView.animate(withDuration: 0.25) {
self.tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: self.tableView.bounds.size.width, height: self.dummyViewHeight))
self.tableView.contentInset = UIEdgeInsets(top: -self.dummyViewHeight, left: 0, bottom: 0, right: 0)
}
}