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I've been using the accepted answer here for years.
On iOS 7, the contentSize.height becomes the frame.height-8, regardless of text content.
What's a working method to adjust the height on iOS 7?
I favor this minimal code change: Just add these two lines after addSubview and before grabbing the height of the frame
...
[scrollView1 addSubview: myTextView];
[myTextView sizeToFit]; //added
[myTextView layoutIfNeeded]; //added
CGRect frame = myTextView.frame;
...
This is tested backwards compatible with iOS 6. NOTE that it shrink-wraps the width. If you're just interested in the height and have a fixed width, just grab the new height but set the original width, and it works just as before on both iOS 6 and 7.
(Speculation: it does size to fit on iOS 7 as well, but the layout is updated later or in a separate thread, and that this forces the layout immediately so that its frame is updated in time for using its height value a few lines later in the same thread.)
NOTES:
1) You might or might not have implemented the outer container resize this way. It does seem to be a common snippet, though, and I've used it in my projects.
2) Since sizeToFit seems to work as expected on iOS 7, you likely don't need the premature addSubView. Whether it will still work on iOS 6 then is untested by me.
3) Speculation: The extra layoutIfNeeded mid-thread might be costly. The alternative as I see it is to resize the outer container on the layout callback (fired or not depending on if the OS decides whether layout is needed or not) where the outer container resize will cause another layout update. Both updates might be combined with other layout updates to be more efficient. If you do have such a solution and you can show that it is more efficient, add it as answer and I'll be sure to mention it here.
Since I'm using Auto Layout, I use the value of [textView sizeThatFits:CGSizeMake(textView.frame.size.width, CGFLOAT_MAX)].height to update the constant of the textView's height UILayoutConstraint.
I use an adapted version of madmik's answer that eliminates the fudge factor:
- (CGFloat)measureHeightOfUITextView:(UITextView *)textView
{
if ([textView respondsToSelector:#selector(snapshotViewAfterScreenUpdates:)])
{
// This is the code for iOS 7. contentSize no longer returns the correct value, so
// we have to calculate it.
//
// This is partly borrowed from HPGrowingTextView, but I've replaced the
// magic fudge factors with the calculated values (having worked out where
// they came from)
CGRect frame = textView.bounds;
// Take account of the padding added around the text.
UIEdgeInsets textContainerInsets = textView.textContainerInset;
UIEdgeInsets contentInsets = textView.contentInset;
CGFloat leftRightPadding = textContainerInsets.left + textContainerInsets.right + textView.textContainer.lineFragmentPadding * 2 + contentInsets.left + contentInsets.right;
CGFloat topBottomPadding = textContainerInsets.top + textContainerInsets.bottom + contentInsets.top + contentInsets.bottom;
frame.size.width -= leftRightPadding;
frame.size.height -= topBottomPadding;
NSString *textToMeasure = textView.text;
if ([textToMeasure hasSuffix:#"\n"])
{
textToMeasure = [NSString stringWithFormat:#"%#-", textView.text];
}
// NSString class method: boundingRectWithSize:options:attributes:context is
// available only on ios7.0 sdk.
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
NSDictionary *attributes = #{ NSFontAttributeName: textView.font, NSParagraphStyleAttributeName : paragraphStyle };
CGRect size = [textToMeasure boundingRectWithSize:CGSizeMake(CGRectGetWidth(frame), MAXFLOAT)
options:NSStringDrawingUsesLineFragmentOrigin
attributes:attributes
context:nil];
CGFloat measuredHeight = ceilf(CGRectGetHeight(size) + topBottomPadding);
return measuredHeight;
}
else
{
return textView.contentSize.height;
}
}
Based on other answers, I made it work(in Swift).
This solves the problem with newline character.
textView.sizeToFit()
textView.layoutIfNeeded()
let height = textView.sizeThatFits(CGSizeMake(textView.frame.size.width, CGFloat.max)).height
textView.contentSize.height = height
Auto Layout is needed.
If you're using Auto Layout, you could create a trivial UITextView subclass that self-sizes the text view height to fit the content:
#interface ContentHeightTextView : UITextView
#end
#interface ContentHeightTextView ()
#property (nonatomic, strong) NSLayoutConstraint *heightConstraint;
#end
#implementation ContentHeightTextView
- (void)layoutSubviews
{
[super layoutSubviews];
CGSize size = [self sizeThatFits:CGSizeMake(self.bounds.size.width, FLT_MAX)];
if (!self.heightConstraint) {
self.heightConstraint = [NSLayoutConstraint constraintWithItem:self attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:0 multiplier:1.0f constant:size.height];
[self addConstraint:self.heightConstraint];
}
self.heightConstraint.constant = size.height;
[super layoutSubviews];
}
#end
Of course, the text view's width and position must be defined by additional constraints configured elsewhere in the program.
If you create this custom text view in IB, give the text view a height constraint in order to satisfy Xcode; just make sure the height constraint created in IB is merely a placeholder (i.e., tick the box that says "Remove at build time").
An alternative way to implement the UITextView subclass is as follows (this implementation might qualify as best practice):
#interface ContentHeightTextView ()
#property (nonatomic, strong) NSLayoutConstraint *heightConstraint;
#end
#implementation ContentHeightTextView
- (void)layoutSubviews
{
[super layoutSubviews];
[self setNeedsUpdateConstraints];
}
- (void)updateConstraints
{
CGSize size = [self sizeThatFits:CGSizeMake(self.bounds.size.width, FLT_MAX)];
if (!self.heightConstraint) {
self.heightConstraint = [NSLayoutConstraint constraintWithItem:self attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:0 multiplier:1.0f constant:size.height];
[self addConstraint:self.heightConstraint];
}
self.heightConstraint.constant = size.height;
[super updateConstraints];
}
#end
If you are using auto-layout, you can use the following UITextView subclass that adds an intrinsic height:
#implementation SelfSizingTextView
- (void)setText:(NSString *)text
{
[super setText:text];
[self invalidateIntrinsicContentSize];
}
- (void)setFont:(UIFont *)font
{
[super setFont:font];
[self invalidateIntrinsicContentSize];
}
- (CGSize)intrinsicContentSize
{
CGFloat width = self.frame.size.width;
CGSize size = [self sizeThatFits:CGSizeMake(width, MAXFLOAT)];
return CGSizeMake(UIViewNoIntrinsicMetric, size.height);
}
#end
this method seems to work.
// 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;
}
}
If you're using iOS 7+, you can just turn on auto layout, pin each of the sides of the text view to the edge of its parent view, and it works fine. No additional code needed.
Not sure if this was always the case but the following is true since at least iOS 10.
UITextView implements the intrinsicContentSize property if scrollEnabled == NO. That means you just need to make sure the width of the text view is constrained enough and then you can use the intrinsic content height (either via Auto Layout content hugging/compression resistance priorities or directly using the value during manual layout).
Unfortunately, this behavior is not documented. Apple could have easily saved us all some headaches… no need for an extra height constraint, subclassing, etc.
In iOS 8 you'll in inherit some content offset from the parent, which you need to get rid of as well.
A subclass example
// Originally from https://github.com/Nikita2k/resizableTextView
#import "ResizableTextView.h"
#implementation ResizableTextView
- (void) updateConstraints {
// calculate contentSize manually
// ios7 doesn't calculate it before viewDidAppear and we'll get here before
CGSize contentSize = [self sizeThatFits:CGSizeMake(self.frame.size.width, FLT_MAX)];
// set the height constraint to change textView height
[self.constraints enumerateObjectsUsingBlock:^(NSLayoutConstraint *constraint, NSUInteger idx, BOOL *stop) {
if (constraint.firstAttribute == NSLayoutAttributeHeight) {
constraint.constant = contentSize.height;
*stop = YES;
}
}];
[super updateConstraints];
}
- (void)setContentOffset:(CGPoint)contentOffset
{
// In iOS 8 we seem to be inheriting the content offset from the parent.
// I'm not interested
}
#end
In storyboard, if using constraints, make sure you are constrained to your superview in the 'ruler' tab of the right-hand pane on xcode for the UITextView. My problem was that I had a constraint of -80 pts on the 'Trailing space to'.
Guys using autolayout and your sizetofit isn't working, then please check your width constraint once. If you had missed the width constraint then the height will be accurate.
No need to use any other API. just one line would fix all the issue.
[_textView sizeToFit];
Here, I was only concerned with height, keeping the width fixed and had missed the width constraint of my TextView in storyboard.
And this was to show up the dynamic content from the services.
Hope this might help..
I wrote a category over UITextView:
- (CGSize)intrinsicContentSize {
return self.contentSize;
}
- (void)setContentSize:(CGSize)contentSize {
[super setContentSize:contentSize];
[self invalidateIntrinsicContentSize];
}
When UIKit sets its contentSize, UITextView adjusts its intrinsic content size. That plays nicely with autolayout.
The answer given by bilobatum worked perfectly With auto layout, i.e subclassing the textview.
If you want to limit the height of the text view add another constraint (I added it using storyboard i.e. height <= 166 (height as per your need))
Then inside subclass reduce the priority of height constraint to 750 (self.heightConstraint.priority = 750) to avoid conflict between height constraint added in subclass and height constraint added on storyboard.
I'm trying to add some perspective on a UILabel, to make it display as if it's painted over an angled face.
Here's my test label:
And after applying the transform:
My code:
#implementation MyViewController
- (void)viewDidLoad {
[super viewDidLoad];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(100.f, 250.f, 100.f, 30.f)];
label.text = #"Hello";
label.textAlignment = NSTextAlignmentCenter;
label.backgroundColor = [UIColor greenColor];
[label tiltDegrees:20.f];
[self.view addSubview:label];
[label release];
}
#end
#implementation UIView (Perspective)
-(void) tiltDegrees:(CGFloat)degrees {
CATransform3D aTransform = CATransform3DIdentity;
CGFloat zDistance = 100; // affects the sharpness of the transform
aTransform.m34 = 1.0 / -zDistance;
aTransform = CATransform3DRotate(aTransform, degrees * M_PI / 180.0f, 1.0f, 0.0f, 0.0f);
self.layer.transform = aTransform;
}
#end
I'm stuck with a bunch of problems:
The text inside the label doesn't seem to apply the transformation in the same way as the UILabel itself does. It's out of frame (clipped), not centered, and the geometry doesn't seem right. Maybe size is wrong too?
It is blurred. How could I apply the transform on the text vector before it is rasterized. I think that would produce crisp results.
I can't seem to work out the coordination between zDistance and the degrees of rotation, so that they result in a correct perspective. How can I calculate zDistance correctly based on degrees?
Any help to solve (1) (2) (3) would be greatly appreciated.
Many Thanks
I don't know if you already solved this, but the problem is basically that your text label is passing through the gray layer behind it, hence why it seems to clip in the middle of the text.
Translate the text layer towards the camera to solve this problem.
I am trying to create a higher resolution image of a UIView, specifically UITextView.
This question and answer is exactly what I am trying to figure out:
Retain the resolution of the label after scaling in iphone
But, when I do the same, my text is still blurry:
self.view.transform = CGAffineTransformMakeScale(2.f, 2.f);
[myText setContentScaleFactor:2.f]; // myText is a subview of self.view object
I have also tried the same in the Apple sample project "UICatalog" to UILabel and it is also blurry.
I can't understand why it would work for Warrior from the other question and not for me. I would have asked there — but I can't seem to leave a comment or a question there.
Setting the contentScaleFactor and contentsScale is in fact the key, as #dbotha pointed out, however you have to walk the view and layer hierarchies separately in order to reach every internal CATiledLayer that actually does the text rendering. Adding the screen scale might also make sense.
So the correct implementation would be something like this:
- (void)updateForZoomScale:(CGFloat)zoomScale {
CGFloat screenAndZoomScale = zoomScale * [UIScreen mainScreen].scale;
// Walk the layer and view hierarchies separately. We need to reach all tiled layers.
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toView:self.textView];
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toLayer:self.textView.layer];
}
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}
- (void)applyScale:(CGFloat)scale toLayer:(CALayer *)layer {
layer.contentsScale = scale;
for (CALayer *sublayer in layer.sublayers) {
[self applyScale:scale toLayer:sublayer];
}
}
UITextView has textInputView property, which "both draws the text and provides a coordinate system" (https://developer.apple.com/reference/uikit/uitextinput/1614564-textinputview)
So i'm using the following code to scale UITextView - without any font changes, without using any "CALayer" property and keeping high quality:
float screenScaleFactor = [[UIScreen mainScreen] scale];
float scale = 5.0;
textView.transform = CGAffineTransformMakeScale(scale, scale);
textView.textInputView.contentScaleFactor = screenScaleFactor * scale;
Comment the last line if you need low quality (but better performance) scaling.
Transform uses view.center as scaling center point, so adding a 'translate transform' is needed to scale around view corner.
Be sure to apply the contentScaleFactor to all subviews of the UITextView. I've just tested the following with a UITextView and found it to work:
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
view.layer.contentsScale = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}
I have a UIView that I'd like to add several bits of text to. I have used a UITextView but I think that's overkill as it doesn't need to be editable. I thought about using a UILabel or a UITextField, but I don't see how you tell the superview where to position the UILabel or UITextField within itself. I want the lowest footprint object that will let me put text of a font/color/size of my choosing in my UIView where I want it. Not too much to ask, eh?
The simplest approach for you would be:
UILabel *yourLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 300, 20)];
[yourLabel setTextColor:[UIColor blackColor]];
[yourLabel setBackgroundColor:[UIColor clearColor]];
[yourLabel setFont:[UIFont fontWithName: #"Trebuchet MS" size: 14.0f]];
[yourSuperView addSubview:yourLabel];
Building or populating Views in your code will probably require you to use CGRectMake a lot.
As its name says, it creates a rectangle that you can use to set the relative position (relative to the borders of your superview) and size of your UIView-Subclass (in this case a UILabel).
It works like this:
yourLabel.Frame = CGRectMake(x, y, width, height); //x,y,width,height are float values.
x defines the spacing between the left hand border of the superview and the beginning of the subview your about to add, same applies to y but relating to the spacing between top-border of your superview.
then width and height are self-explanatory i think.
Hope this gets you on the track.
Instead of finding a way to tell the view where to position the UILabel, you can tell the UILabel where to position itself in the view by using "center".
E.g.
myLabel.center = CGPointMake(0.0, 0.0);
Hope you'll be able to use UILabel, for me it's the basic form of a flexible non editable text.
For Swift:
let yourLabel = UILabel(frame: CGRectMake(100, 100, 100, 100))
yourLabel.textColor = UIColor.whiteColor()
yourLabel.backgroundColor = UIColor.blackColor()
yourLabel.text = "mylabel text"
yoursuperview.addSubview(yourLabel)
This question is old, but for a pure UIView text option without using UILabel or UITextField (as all the other answers describe, but the question is how to do it without them), drawRect in a subclassed UIView works for me. Like so:
- (void)drawRect:(CGRect)rect{
NSString *string = #"Hello World!";
[string drawAtPoint:CGPointMake(100, 100) withFont:[UIFont boldSystemFontOfSize:16.0]];
}
This routine displays a text at a X-Y position
-(void)placeText:(NSString *)theText:(int)theX:(int)theY {
UILabel *textLabel;
// Set font and calculate used space
UIFont *textFont = [UIFont fontWithName:#"Helvetica" size:14];
CGSize textStringSize = [theText sizeWithFont:textFont constrainedToSize:CGSizeMake(300,50) lineBreakMode:NSLineBreakByTruncatingTail];
// Position of the text
textLabel = [[UILabel alloc] initWithFrame:CGRectMake(theX+OFFSETIMAGEX-(textStringSize.width/2), theY+OFFSETIMAGEY-(textStringSize.height/2), textStringSize.width,textStringSize.height)];
// Set text attributes
textLabel.textColor = [UIColor blackColor];
textLabel.backgroundColor = [UIColor orangeColor];
textLabel.font = textFont;
textLabel.text = theText;
// Display text
[self.view addSubview:textLabel];
}
It might be late but here is what I use:-
CGRect labelFrame = CGRectMake(120,300, 530, 100);
UILabel *myLabel = [[UILabel alloc] initWithFrame:labelFrame];
//If you need to change the color
[myLabel setTextColor:[UIColor whiteColor]];
//If you need to change the system font
[myLabel setFont:[UIFont fontWithName:NULL size:23]];
//If you need alignment
[myLabel setTextAlignment:NSTextAlignmentCenter];
// The label will use an unlimited number of lines
[myLabel setNumberOfLines:0];
//Add label view to current view
[self.view addSubview:myLabel];
NSString *someString = #"Sample String, Yarp!";
myLabel.text = someString;
add a UILabel to your View. then override the View's layoutSubviews method.
How would one modify the following snippet (in a tableView:cellForRowAtIndexPath: UITableViewController method) from the "09a - PrefsTable" recipe from Chapter 6 of The iPhone Developer's Cookbook:
if (row == 1) {
// Create a big word-wrapped UILabel
cell = [tableView dequeueReusableCellWithIdentifier:#"libertyCell"];
if (!cell) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:#"libertyCell"] autorelease];
[cell addSubview:[[UILabel alloc] initWithFrame:CGRectMake(20.0f, 10.0f, 280.0f, 330.0f)]];
}
UILabel *sv = [[cell subviews] lastObject];
sv.text = #"When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.";
sv.textAlignment = UITextAlignmentCenter;
sv.lineBreakMode = UILineBreakModeWordWrap;
sv.numberOfLines = 9999;
return cell;
}
...to size the "sv" UILabel subview and the "cell" UITableViewCell to be sized just big enough to fit the text (and work with more or less text, and other types of text alignment)? I looked at the UILabel textRectForBounds:limitedToNumberOfLines: method, but the documentation states that it should not be called directly (and should only be overridden). I experimented with the UIView sizeToFit method, without success.
Update: I asked a new question about my problem with the NSString -sizeWithFont:forWidth:lineBreakMode: method.
I had to do this enough that I extended UILabel to do it for me:
#interface UILabel (BPExtensions)
- (void)sizeToFitFixedWidth:(CGFloat)fixedWidth;
#end
#implementation UILabel (BPExtensions)
- (void)sizeToFitFixedWidth:(CGFloat)fixedWidth
{
self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, fixedWidth, 0);
self.lineBreakMode = NSLineBreakByWordWrapping;
self.numberOfLines = 0;
[self sizeToFit];
}
#end
then to have a label to have a variable multiline height but a fixed width just:
[myLabel sizeToFitFixedWidth:kSomeFixedWidth];
You should use NSString's -sizeWithFont:forWidth:lineBreakMode: method to retrieve the associated sizing metrics for your label.
Also, change the numberOfLines property to 0 if you're going to use that code.
NSString's -sizeWithFont:forWidth:lineBreakMode: does not actually perform the word wrap. Instead, use -sizeWithFont:constrainedToSize:lineBreakMode: to get an accurate width AND height value for the string.
Try this:
sv.text = #"When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.";
sv.textAlignment = UITextAlignmentCenter;
sv.lineBreakMode = UILineBreakModeWordWrap;
sv.numberOfLines = 0;
[sv sizeToFit];
Also, you will need to implement the UITableViewDelegate method:
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
And have it return a total cell height adjusted for the resized text field.
One other note - Size to Fit should actually work, if you have number of lines set to 0 as previously mentioned. It would give you back a size with the height increased to accomidate the word-wrapped text set in the label and the width set to whatever the original label width had.
That will not help you though as you need to get the size in heightForRow before the cell is obtained, so you are better off calculating the height needed (and very probably caching that calculation so as not to slow down table rendering)
Here's a bit of code i use:
CGSize textSize = [myLabel.text sizeWithFont:myLabel.font];
I had similar problem, I had a UITableViewCell that was designed in StoryBoards as a static cell. I used [super tableView:cellForRowAtIndexPath:] to get it. So I wanted to resize the UILabel "detailTextLabel" so it fits the text I set to it. The style was "Right Detail".
I just set the text in my tableView:cellForRowAtIndexPath:. And than in tableView:heightForRowAtIndexPath: I returned
UITableViewCell *cell = [super tableView:tableView cellForRowAtIndexPath:indexPath];
return cell.detailTextLabel.frame.size.height
I had long string. And finally had a wide Cell with 4 lines of text in label.
I had similar problem.
I solved this.
In cellForRowAtIndexPath method set font size to whatever you want.
cell.textLabel.lineBreakMode = UILineBreakModeWordWrap;
cell.textLabel.numberOfLines = 0;
[cell.textLabel setFont:[UIFont systemFontOfSize:14.0]];
[cell.textLabel sizeToFit];
And in heightForRowAtIndexPath method increase font size.
CGFloat height;
UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:indexPath];
NSString *text = cell.detailTextLabel.text;
CGSize constraint = CGSizeMake(320, 20000.0f);
CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:20.0] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];
CGFloat calHeight = MAX(size.height, 44.0f);
height = calHeight + (CELL_CONTENT_MARGIN * 2);
return height;