是否有一个好的方法来调整UITextView的大小以符合其内容?例如,我有一个包含一行文本的UITextView:
"Hello world"
然后我添加了另一行文本:
"Goodbye world"
在Cocoa Touch中是否有一个好的方法来获取矩形来保存文本视图中的所有行,这样我就可以相应地调整父视图?
另一个例子是,查看Calendar应用程序中用于事件的notes字段——注意单元格(以及它包含的UITextView)如何展开以保存notes字符串中的所有文本行。
是否有一个好的方法来调整UITextView的大小以符合其内容?例如,我有一个包含一行文本的UITextView:
"Hello world"
然后我添加了另一行文本:
"Goodbye world"
在Cocoa Touch中是否有一个好的方法来获取矩形来保存文本视图中的所有行,这样我就可以相应地调整父视图?
另一个例子是,查看Calendar应用程序中用于事件的notes字段——注意单元格(以及它包含的UITextView)如何展开以保存notes字符串中的所有文本行。
当前回答
禁用滚动
添加constaints
然后添加文本
[yourTextView setText:@"your text"];
[yourTextView layoutIfNeeded];
如果你使用UIScrollView,你也应该添加这个;
[yourScrollView layoutIfNeeded];
-(void)viewDidAppear:(BOOL)animated{
CGRect contentRect = CGRectZero;
for (UIView *view in self.yourScrollView.subviews) {
contentRect = CGRectUnion(contentRect, view.frame);
}
self.yourScrollView.contentSize = contentRect.size;
}
其他回答
这个方法似乎适用于ios7
// Code from apple developer forum - @Steve Krulewitz, @Mark Marszal, @Eric Silverberg
- (CGFloat)measureHeight
{
if ([self respondsToSelector:@selector(snapshotViewAfterScreenUpdates:)])
{
CGRect frame = internalTextView.bounds;
CGSize fudgeFactor;
// The padding added around the text on iOS6 and iOS7 is different.
fudgeFactor = CGSizeMake(10.0, 16.0);
frame.size.height -= fudgeFactor.height;
frame.size.width -= fudgeFactor.width;
NSMutableAttributedString* textToMeasure;
if(internalTextView.attributedText && internalTextView.attributedText.length > 0){
textToMeasure = [[NSMutableAttributedString alloc] initWithAttributedString:internalTextView.attributedText];
}
else{
textToMeasure = [[NSMutableAttributedString alloc] initWithString:internalTextView.text];
[textToMeasure addAttribute:NSFontAttributeName value:internalTextView.font range:NSMakeRange(0, textToMeasure.length)];
}
if ([textToMeasure.string hasSuffix:@"\n"])
{
[textToMeasure appendAttributedString:[[NSAttributedString alloc] initWithString:@"-" attributes:@{NSFontAttributeName: internalTextView.font}]];
}
// NSAttributedString class method: boundingRectWithSize:options:context is
// available only on ios7.0 sdk.
CGRect size = [textToMeasure boundingRectWithSize:CGSizeMake(CGRectGetWidth(frame), MAXFLOAT)
options:NSStringDrawingUsesLineFragmentOrigin
context:nil];
return CGRectGetHeight(size) + fudgeFactor.height;
}
else
{
return self.internalTextView.contentSize.height;
}
}
我找到了一种方法,根据里面的文本调整文本字段的高度,并根据文本字段的高度在下面安排一个标签!这是代码。
UITextView *_textView = [[UITextView alloc] initWithFrame:CGRectMake(10, 10, 300, 10)];
NSString *str = @"This is a test text view to check the auto increment of height of a text view. This is only a test. The real data is something different.";
_textView.text = str;
[self.view addSubview:_textView];
CGRect frame = _textView.frame;
frame.size.height = _textView.contentSize.height;
_textView.frame = frame;
UILabel *lbl = [[UILabel alloc] initWithFrame:CGRectMake(10, 5 + frame.origin.y + frame.size.height, 300, 20)];
lbl.text = @"Hello!";
[self.view addSubview:lbl];
以下是步骤
解决方案适用于所有版本的iOS。Swift 3.0及以上版本。
添加你的UITextView到View。我用代码添加它,你可以通过界面生成器添加。 添加约束。我在代码中添加约束,你也可以在接口生成器中这样做。 使用UITextViewDelegate方法func textViewDidChange(_ textView: UITextView)来调整textView的大小
代码:
//1. Add your UITextView in ViewDidLoad let textView = UITextView() textView.frame = CGRect(x: 0, y: 0, width: 200, height: 100) textView.backgroundColor = .lightGray textView.text = "Here is some default text." //2. Add constraints textView.translatesAutoresizingMaskIntoConstraints = false [ textView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor), textView.leadingAnchor.constraint(equalTo: view.leadingAnchor), textView.trailingAnchor.constraint(equalTo: view.trailingAnchor), textView.heightAnchor.constraint(equalToConstant: 50), textView.widthAnchor.constraint(equalToConstant: 30) ].forEach{ $0.isActive = true } textView.font = UIFont.preferredFont(forTextStyle: .headline) textView.delegate = self textView.isScrollEnabled = false textViewDidChange(textView) //3. Implement the delegate method. func textViewDidChange(_ textView: UITextView) { let size = CGSize(width: view.frame.width, height: .infinity) let estimatedSize = textView.sizeThatFits(size) textView.constraints.forEach { (constraint) in if constraint.firstAttribute == .height { print("Height: ", estimatedSize.height) constraint.constant = estimatedSize.height } } }
禁用滚动
添加constaints
然后添加文本
[yourTextView setText:@"your text"];
[yourTextView layoutIfNeeded];
如果你使用UIScrollView,你也应该添加这个;
[yourScrollView layoutIfNeeded];
-(void)viewDidAppear:(BOOL)animated{
CGRect contentRect = CGRectZero;
for (UIView *view in self.yourScrollView.subviews) {
contentRect = CGRectUnion(contentRect, view.frame);
}
self.yourScrollView.contentSize = contentRect.size;
}
不知道为什么人们总是把事情复杂化: 下面就是:
- (void)textViewDidChange:(UITextView *)textView{ CGRect frame = textView.frame;
CGFloat height = [self measureHeightOfUITextView:textView];
CGFloat insets = textView.textContainerInset.top + textView.textContainerInset.bottom;
height += insets;
frame.size.height = height;
if(frame.size.height > textView.frame.size.height){
CGFloat diff = frame.size.height - textView.frame.size.height;
textView.frame = CGRectMake(5, textView.frame.origin.y - diff, textView.frame.size.width, frame.size.height);
}
else if(frame.size.height < textView.frame.size.height){
CGFloat diff = textView.frame.size.height - frame.size.height;
textView.frame = CGRectMake(5, textView.frame.origin.y + diff, textView.frame.size.width, frame.size.height);
}
[textView setNeedsDisplay];
}