我有一个包含全屏UITextView
的视图控制器。当键盘出现时,我希望调整文本视图的大小,以便不会被键盘遮挡。
这是iOS中相当标准的做法,如在以下问题中所述:
然而,在iOS 7上,如果用户点击屏幕下半部分的文本视图,当文本视图重新调整大小时,光标仍然偏离屏幕。只有当用户按回车键时,文本视图才会滚动以使光标可见。
我有一个包含全屏UITextView
的视图控制器。当键盘出现时,我希望调整文本视图的大小,以便不会被键盘遮挡。
这是iOS中相当标准的做法,如在以下问题中所述:
然而,在iOS 7上,如果用户点击屏幕下半部分的文本视图,当文本视图重新调整大小时,光标仍然偏离屏幕。只有当用户按回车键时,文本视图才会滚动以使光标可见。
我阅读了关于这个话题的文档。我将它翻译成Swift并且它对我非常有效。
这适用于像iMessage那样的全屏UITextView。
我正在使用iOS 8.2和XCode 6.2上的Swift,这是我的代码。只需从您的viewDidLoad
或其他初始化方法中调用此setupKeyboardNotifications
即可。
func setupKeyboardNotifications() {
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWasShown(aNotification:NSNotification) {
let info = aNotification.userInfo
let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
let kbSize = infoNSValue.CGRectValue().size
let contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0)
codeTextView.contentInset = contentInsets
codeTextView.scrollIndicatorInsets = contentInsets
}
func keyboardWillBeHidden(aNotification:NSNotification) {
let contentInsets = UIEdgeInsetsZero
codeTextView.contentInset = contentInsets
codeTextView.scrollIndicatorInsets = contentInsets
}
如果你在旋转时发现光标位置不正确,请检查方向变化并滚动到正确的位置。
override func didRotateFromInterfaceOrientation(fromInterfaceOrientation: UIInterfaceOrientation) {
scrollToCaretInTextView(codeTextView, animated: true)
}
func scrollToCaretInTextView(textView:UITextView, animated:Bool) {
var rect = textView.caretRectForPosition(textView.selectedTextRange?.end)
rect.size.height += textView.textContainerInset.bottom
textView.scrollRectToVisible(rect, animated: animated)
}
Swift 3:
func configureKeyboardNotifications() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(aNotification:)), name: NSNotification.Name.UIKeyboardDidShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(aNotification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func keyboardWasShown(aNotification:NSNotification) {
let info = aNotification.userInfo
let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as! NSValue
let kbSize = infoNSValue.cgRectValue.size
let contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0)
textView.contentInset = contentInsets
textView.scrollIndicatorInsets = contentInsets
}
func keyboardWillBeHidden(aNotification:NSNotification) {
let contentInsets = UIEdgeInsets.zero
textView.contentInset = contentInsets
textView.scrollIndicatorInsets = contentInsets
}
Swift 4 & 5:
func setupKeyboardNotifications() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_ :)), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
}
@objc func keyboardWillShow(_ notification:NSNotification) {
let d = notification.userInfo!
var r = (d[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
r = self.textView.convert(r, from:nil)
self.textView.contentInset.bottom = r.size.height
self.textView.verticalScrollIndicatorInsets.bottom = r.size.height
}
@objc func keyboardWillHide(_ notification:NSNotification) {
let contentInsets = UIEdgeInsets.zero
self.textView.contentInset = contentInsets
self.textView.verticalScrollIndicatorInsets = contentInsets
}
或者,查看LeoNatan的回复。那可能是一个更清晰、更简单的解决方案(我还没有尝试过)。
contentInset
解决方案来改进您的应用程序。 - Léo NatancontentInset
和scrollIndicatorInsets
底部设置为键盘的高度。- (void)textViewDidBeginEditing:(UITextView *)textView
{
_caretVisibilityTimer = [NSTimer scheduledTimerWithTimeInterval:0.3 target:self selector:@selector(_scrollCaretToVisible) userInfo:nil repeats:YES];
}
- (void)_scrollCaretToVisible
{
//This is where the cursor is at.
CGRect caretRect = [self.textView caretRectForPosition:self.textView.selectedTextRange.end];
if(CGRectEqualToRect(caretRect, _oldRect))
return;
_oldRect = caretRect;
//This is the visible rect of the textview.
CGRect visibleRect = self.textView.bounds;
visibleRect.size.height -= (self.textView.contentInset.top + self.textView.contentInset.bottom);
visibleRect.origin.y = self.textView.contentOffset.y;
//We will scroll only if the caret falls outside of the visible rect.
if(!CGRectContainsRect(visibleRect, caretRect))
{
CGPoint newOffset = self.textView.contentOffset;
newOffset.y = MAX((caretRect.origin.y + caretRect.size.height) - visibleRect.size.height + 5, 0);
[self.textView setContentOffset:newOffset animated:NO];
}
}
优化了原有光标位置设置和禁用动画的设置。现在看起来已经运行良好。
@implementation ViewController {
CGSize _keyboardSize;
UITextView* textView;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
textView = [[UITextView alloc] initWithFrame:CGRectInset(self.view.bounds, 20.0, 20.0)]; textView.delegate = self;
textView.returnKeyType = UIReturnKeyDone;
textView.backgroundColor = [UIColor greenColor];
textView.textColor = [UIColor blackColor];
[self.view addSubview:textView];
NSMutableString *textString = [NSMutableString new];
for (int i=0; i<100; i++) {
[textString appendString:@"cheese\rpizza\rchips\r"];
}
textView.text = textString;
}
- (void)textViewDidBeginEditing:(UITextView *)textView1 {
CGRect textViewFrame = CGRectInset(self.view.bounds, 20.0, 20.0);
textViewFrame.size.height -= 216;
textView.frame = textViewFrame;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
CGRect textViewFrame = CGRectInset(self.view.bounds, 20.0, 20.0);
textView.frame = textViewFrame;
[textView endEditing:YES];
[super touchesBegan:touches withEvent:event];
}
@end
注意: 不幸的是,textViewDidBeginEdting
在 UIKeyboardWillShowNotification
通知之前触发,因此需要硬编码键盘高度。
@interface ViewController : UIViewController <UITextViewDelegate> {
UITextView *textView ;
}
@property(nonatomic,strong)IBOutlet UITextView *textView;
@end
.m文件
@implementation ViewController
@synthesize textView;
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
CGRect textViewFrame = CGRectMake(20.0f, 20.0f, 280.0f, 424.0f);
//UITextView *textView = [[UITextView alloc] initWithFrame:textViewFrame];
textView.frame = textViewFrame;
textView.delegate = self;
textView.returnKeyType = UIReturnKeyDone;
textView.backgroundColor = [UIColor greenColor];
textView.textColor = [UIColor blackColor];
[self.view addSubview:textView];
}
- (BOOL)textViewShouldBeginEditing:(UITextView *)textView{
NSLog(@"textViewShouldBeginEditing:");
return YES;
}
- (void)textViewDidBeginEditing:(UITextView *)textView1 {
NSLog(@"textViewDidBeginEditing:");
CGRect textViewFrame = CGRectMake(20.0f, 20.0f, 280.0f, 224.0f);
textView1.frame = textViewFrame;
}
- (BOOL)textViewShouldEndEditing:(UITextView *)textView{
NSLog(@"textViewShouldEndEditing:");
return YES;
}
- (void)textViewDidEndEditing:(UITextView *)textView{
NSLog(@"textViewDidEndEditing:");
}
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
return YES;
}
- (void)textViewDidChange:(UITextView *)textView{
NSLog(@"textViewDidChange:");
}
- (void)textViewDidChangeSelection:(UITextView *)textView{
NSLog(@"textViewDidChangeSelection:");
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(@"touchesBegan:withEvent:");
CGRect textViewFrame = CGRectMake(20.0f, 20.0f, 280.0f, 424.0f);
textView.frame = textViewFrame;
[self.view endEditing:YES];
[super touchesBegan:touches withEvent:event];
}
@end
@Johnston 找到了一个好的解决方案。这里有一个变体,使用 UIKeyboardWillChangeFrameNotification
来正确处理键盘大小的更改(即显示/隐藏 QuickType 栏)。它还可以正确处理文本视图嵌入导航控制器的情况(即 contentInset
不为零)。它也是用 Swift 2 编写的。
override func viewDidLoad() {
:
NSNotificationCenter.defaultCenter().addObserverForName(UIKeyboardWillChangeFrameNotification, object: nil, queue: nil) { (notification) -> Void in
guard let userInfo = notification.userInfo,
let keyboardFrameEndValue = userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue
else { return }
let windowCoordinatesKeyboardFrameEnd = keyboardFrameEndValue.CGRectValue() // window coordinates
let keyboardFrameEnd = self.view.convertRect(windowCoordinatesKeyboardFrameEnd, fromView: nil) // view coordinates
var inset = self.textView.contentInset
inset.bottom = CGRectGetMaxY(self.textView.frame) - CGRectGetMinY(keyboardFrameEnd) // bottom inset is the bottom of textView minus top of keyboard
self.textView.contentInset = inset
self.textView.scrollIndicatorInsets = inset
}
}
我已经完成了它,而且它完全可行。
#define k_KEYBOARD_OFFSET 95.0
-(void)keyboardWillAppear {
// Move current view up / down with Animation
if (self.view.frame.origin.y >= 0)
{
[self moveViewUp:NO];
}
else if (self.view.frame.origin.y < 0)
{
[self moveViewUp:YES];
}
}
-(void)keyboardWillDisappear {
if (self.view.frame.origin.y >= 0)
{
[self moveViewUp:YES];
}
else if (self.view.frame.origin.y < 0)
{
[self moveViewUp:NO];
}
}
-(void)textFieldDidBeginEditing:(UITextField *)sender
{
//if ([sender isEqual:_txtPassword])
// {
//move the main view up, so the keyboard will not hide it.
if (self.view.frame.origin.y >= 0)
{
[self moveViewUp:YES];
}
//}
}
//Custom method to move the view up/down whenever the keyboard is appeared / disappeared
-(void)moveViewUp:(BOOL)bMovedUp
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.4]; // to slide the view up
CGRect rect = self.view.frame;
if (bMovedUp) {
// 1. move the origin of view up so that the text field will come above the keyboard
rect.origin.y -= k_KEYBOARD_OFFSET;
// 2. increase the height of the view to cover up the area behind the keyboard
rect.size.height += k_KEYBOARD_OFFSET;
} else {
// revert to normal state of the view.
rect.origin.y += k_KEYBOARD_OFFSET;
rect.size.height -= k_KEYBOARD_OFFSET;
}
self.view.frame = rect;
[UIView commitAnimations];
}
- (void)viewWillAppear:(BOOL)animated
{
// register keyboard notifications to appear / disappear the keyboard
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillAppear)
name:UIKeyboardWillShowNotification
object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillDisappear)
name:UIKeyboardWillHideNotification
object:nil];
}
- (void)viewWillDisappear:(BOOL)animated
{
// unregister for keyboard notifications while moving to the other screen.
[[NSNotificationCenter defaultCenter] removeObserver:self
name:UIKeyboardWillShowNotification
object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self
name:UIKeyboardWillHideNotification
object:nil];
}
这是我的解决方案,使用Swift 1.2在Xcode 6.4上于2015年7月针对iOS 7.1进行开发 - 结合了几种方法。借用了 Johnston的键盘处理Swift代码。虽然有点hack,但它很简单并且有效。
我在一个单独的视图中放置了一个普通的UITextView。
我不想像 Apple的文档中那样将其嵌入UIScrollView中。我只想在软件键盘出现时重新调整UITextView的大小,并在键盘消失时恢复原始大小。
以下是基本步骤:
接下来是代码部分。
我已经通过界面构建器中的常规拖放设置了代码文件顶部的约束输出口:@IBOutlet weak var myUITextViewBottomConstraint: NSLayoutConstraint!
我还设置了一个全局变量,可以在键盘出现之前备份状态:var myUITextViewBottomConstraintBackup: CGFloat = 0
实现键盘通知,在viewDidLoad或任何其他启动/设置部分中调用此函数:
func setupKeyboardNotifications() {
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWasShown(aNotification:NSNotification) {
let info = aNotification.userInfo
let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as! NSValue
let kbSize = infoNSValue.CGRectValue().size
let newHeight = kbSize.height
//backup old constraint size
myUITextViewBottomConstraintOld = myUITextViewBottomConstraint.constant
// I subtract 50 because otherwise it leaves a gap between keyboard and text view. I'm sure this could be improved on.
myUITextViewBottomConstraint.constant = newHeight - 50
func keyboardWillBeHidden(aNotification:NSNotification) {
//restore to whatever AutoLayout set it before you messed with it
myUITextViewBottomConstraint.constant = myUITextViewBottomConstraintOld
}
代码可以运行,但有一个小问题: