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
Swift最简单的解决方案:
override func viewDidLoad() {
super.viewDidLoad()
searchBar?.becomeFirstResponder()
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(MyViewController.keyboardWillShow(_:)), name: UIKeyboardDidShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(MyViewController.keyboardWillHide(_:)), name: UIKeyboardDidHideNotification, object: nil)
}
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self)
}
func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardHeight = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue.size.height {
tableView.contentInset = UIEdgeInsetsMake(0, 0, keyboardHeight, 0)
}
}
}
func keyboardWillHide(notification: NSNotification) {
UIView.animateWithDuration(0.2, animations: { self.table_create_issue.contentInset = UIEdgeInsetsMake(0, 0, 0, 0) })
// For some reason adding inset in keyboardWillShow is animated by itself but removing is not, that's why we have to use animateWithDuration here
}
Swift 4.2或更高版本
override func viewDidLoad() {
super.viewDidLoad()
searchBar?.becomeFirstResponder()
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: UIResponder.keyboardDidShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide), name: UIResponder.keyboardDidHideNotification, object: nil)
}
deinit {
NotificationCenter.default.removeObserver(self)
}
@objc func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
let keyboardHeight = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as AnyObject).cgRectValue.size.height
accountSettingsTableView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight, right: 0)
}
}
@objc func keyboardWillHide(notification: NSNotification) {
UIView.animate(withDuration: 0.2, animations: { self.accountSettingsTableView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0) })}
}
其他回答
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)
}
如果你使用UITableViewController而不是UIViewController,它会自动这样做。
这非常有效,在iPad上也是如此。
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
if(textField == textfield1){
[accountName1TextField becomeFirstResponder];
}else if(textField == textfield2){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield3 becomeFirstResponder];
}else if(textField == textfield3){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:1 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield4 becomeFirstResponder];
}else if(textField == textfield4){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:2 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield5 becomeFirstResponder];
}else if(textField == textfield5){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:3 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield6 becomeFirstResponder];
}else if(textField == textfield6){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:4 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield7 becomeFirstResponder];
}else if(textField == textfield7){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:5 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield8 becomeFirstResponder];
}else if(textField == textfield8){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:6 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textfield9 becomeFirstResponder];
}else if(textField == textfield9){
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:7 inSection:1] atScrollPosition:UITableViewScrollPositionTop animated:YES];
[textField resignFirstResponder];
}
我想我已经想出了与苹果应用程序行为相匹配的解决方案。
首先,在viewWillAppear:订阅键盘通知,这样你就知道什么时候键盘会显示和隐藏,系统会告诉你键盘的大小,但不要忘记在viewWillDisappear:中取消注册。
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:@selector(keyboardWillShow:)
name:UIKeyboardWillShowNotification
object:nil];
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:@selector(keyboardWillHide:)
name:UIKeyboardWillHideNotification
object:nil];
实现类似于下面的方法,以便在键盘显示时调整tableView的大小以匹配可见区域。这里我单独跟踪键盘的状态,所以我可以自己选择何时将tableView设置为全高度,因为你在每个字段更改时都会收到这些通知。不要忘记实现keyboardWillHide:并选择适当的地方来修复你的tableView大小。
-(void) keyboardWillShow:(NSNotification *)note
{
CGRect keyboardBounds;
[[note.userInfo valueForKey:UIKeyboardBoundsUserInfoKey] getValue: &keyboardBounds];
keyboardHeight = keyboardBounds.size.height;
if (keyboardIsShowing == NO)
{
keyboardIsShowing = YES;
CGRect frame = self.view.frame;
frame.size.height -= keyboardHeight;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:0.3f];
self.view.frame = frame;
[UIView commitAnimations];
}
}
现在这是滚动位,我们先计算出一些大小,然后我们看到我们在可见区域中的位置,并设置我们想要滚动的矩形,根据它在视图中的位置,将它设置为文本字段中间上方或下方的半视图。在本例中,我们有一个UITextFields数组和一个用于跟踪它们的enum,因此用rowHeight乘以行号就得到了这个外部视图中帧的实际偏移量。
- (void) textFieldDidBeginEditing:(UITextField *)textField
{
CGRect frame = textField.frame;
CGFloat rowHeight = self.tableView.rowHeight;
if (textField == textFields[CELL_FIELD_ONE])
{
frame.origin.y += rowHeight * CELL_FIELD_ONE;
}
else if (textField == textFields[CELL_FIELD_TWO])
{
frame.origin.y += rowHeight * CELL_FIELD_TWO;
}
else if (textField == textFields[CELL_FIELD_THREE])
{
frame.origin.y += rowHeight * CELL_FIELD_THREE;
}
else if (textField == textFields[CELL_FIELD_FOUR])
{
frame.origin.y += rowHeight * CELL_FIELD_FOUR;
}
CGFloat viewHeight = self.tableView.frame.size.height;
CGFloat halfHeight = viewHeight / 2;
CGFloat midpoint = frame.origin.y + (textField.frame.size.height / 2);
if (midpoint < halfHeight)
{
frame.origin.y = 0;
frame.size.height = midpoint;
}
else
{
frame.origin.y = midpoint;
frame.size.height = midpoint;
}
[self.tableView scrollRectToVisible:frame animated:YES];
}
这似乎工作得很好。
因此,经过数小时的艰苦工作,尝试使用这些当前的解决方案(完全失败),我终于让事情正常工作,并更新它们以使用新的动画块。我的回答完全基于Ortwin上面的回答。
所以不管出于什么原因,上面的代码就是不适合我。我的设置似乎和其他人的很相似,但可能是因为我用的是iPad或4.3……不知道。它在做一些古怪的数学运算然后把我的tableview从屏幕上拍下来。
见我的解决方案的最终结果:http://screencast.com/t/hjBCuRrPC(请忽略照片。: - p)
所以我沿用了Ortwin的基本原理,但改变了计算原点的方法。Y和尺寸。我的表格视图的高度和键盘的高度。当我从结果中减去窗口的高度时,它告诉我有多少交集。如果它大于0(也就是有一些重叠),我执行帧高度的动画。
此外,还有一些重绘问题得到了解决,1)等待滚动到单元格直到动画完成,2)使用UIViewAnimationOptionBeginFromCurrentState选项隐藏键盘。
有几件事需要注意。
_topmostrowbeforekeyboardwasshow & _originalFrame是在头文件中声明的实例变量。 自我。guestEntryTableView是我的tableView(我在外部文件中) iaskcgrecswap是Ortwin用于翻转帧坐标的方法 我只更新tableView的高度如果它至少有50px会显示 因为我不在UIViewController中,所以我没有self。视图,我只是把tableView返回到它的原始框架
同样,如果我Ortwin没有提供关键,我也不会得到这个答案。代码如下:
- (IBAction)textFieldDidBeginEditing:(UITextField *)textField
{
self.activeTextField = textField;
if ([self.guestEntryTableView indexPathsForVisibleRows].count) {
_topmostRowBeforeKeyboardWasShown = (NSIndexPath*)[[self.guestEntryTableView indexPathsForVisibleRows] objectAtIndex:0];
} else {
// this should never happen
_topmostRowBeforeKeyboardWasShown = [NSIndexPath indexPathForRow:0 inSection:0];
[textField resignFirstResponder];
}
}
- (IBAction)textFieldDidEndEditing:(UITextField *)textField
{
self.activeTextField = nil;
}
- (void)keyboardWillShow:(NSNotification*)notification {
NSDictionary* userInfo = [notification userInfo];
NSValue* keyboardFrameValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];
// Reduce the tableView height by the part of the keyboard that actually covers the tableView
UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
CGRect windowRect = [[UIApplication sharedApplication] keyWindow].bounds;
CGRect viewRectAbsolute = [self.guestEntryTableView convertRect:self.guestEntryTableView.bounds toView:[[UIApplication sharedApplication] keyWindow]];
CGRect keyboardFrame = [keyboardFrameValue CGRectValue];
if (UIInterfaceOrientationLandscapeLeft == orientation ||UIInterfaceOrientationLandscapeRight == orientation ) {
windowRect = IASKCGRectSwap(windowRect);
viewRectAbsolute = IASKCGRectSwap(viewRectAbsolute);
keyboardFrame = IASKCGRectSwap(keyboardFrame);
}
// fix the coordinates of our rect to have a top left origin 0,0
viewRectAbsolute = FixOriginRotation(viewRectAbsolute, orientation, windowRect.size.width, windowRect.size.height);
CGRect frame = self.guestEntryTableView.frame;
_originalFrame = self.guestEntryTableView.frame;
int remainder = (viewRectAbsolute.origin.y + viewRectAbsolute.size.height + keyboardFrame.size.height) - windowRect.size.height;
if (remainder > 0 && !(remainder > frame.size.height + 50)) {
frame.size.height = frame.size.height - remainder;
float duration = [[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
[UIView animateWithDuration: duration
animations:^{
self.guestEntryTableView.frame = frame;
}
completion:^(BOOL finished){
UITableViewCell *textFieldCell = (UITableViewCell*) [[self.activeTextField superview] superview];
NSIndexPath *textFieldIndexPath = [self.guestEntryTableView indexPathForCell:textFieldCell];
[self.guestEntryTableView scrollToRowAtIndexPath:textFieldIndexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
}];
}
}
- (void)keyboardWillHide:(NSNotification*)notification {
NSDictionary* userInfo = [notification userInfo];
float duration = [[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
[UIView animateWithDuration: duration
delay: 0.0
options: (UIViewAnimationOptionBeginFromCurrentState)
animations:^{
self.guestEntryTableView.frame = _originalFrame;
}
completion:^(BOOL finished){
[self.guestEntryTableView scrollToRowAtIndexPath:_topmostRowBeforeKeyboardWasShown atScrollPosition:UITableViewScrollPositionTop animated:YES];
}];
}
#pragma mark CGRect Utility function
CGRect IASKCGRectSwap(CGRect rect) {
CGRect newRect;
newRect.origin.x = rect.origin.y;
newRect.origin.y = rect.origin.x;
newRect.size.width = rect.size.height;
newRect.size.height = rect.size.width;
return newRect;
}
CGRect FixOriginRotation(CGRect rect, UIInterfaceOrientation orientation, int parentWidth, int parentHeight) {
CGRect newRect;
switch(orientation)
{
case UIInterfaceOrientationLandscapeLeft:
newRect = CGRectMake(parentWidth - (rect.size.width + rect.origin.x), rect.origin.y, rect.size.width, rect.size.height);
break;
case UIInterfaceOrientationLandscapeRight:
newRect = CGRectMake(rect.origin.x, parentHeight - (rect.size.height + rect.origin.y), rect.size.width, rect.size.height);
break;
case UIInterfaceOrientationPortrait:
newRect = rect;
break;
case UIInterfaceOrientationPortraitUpsideDown:
newRect = CGRectMake(parentWidth - (rect.size.width + rect.origin.x), parentHeight - (rect.size.height + rect.origin.y), rect.size.width, rect.size.height);
break;
}
return newRect;
}