this is my first question on this message board so please go easy on me :)
A while ago I came across a useful piece of code to change a UILabel, this basically surounds the text in the label with a black (or an other color) outline.
- (void)drawTextInRect:(CGRect)rect; {
CGSize shadowOffset = self.shadowOffset;
UIColor *textColor = self.textColor;
CGContextRef c = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(c, 2);
CGContextSetLineJoin(c, kCGLineJoinRound);
CGContextSetTextDrawingMode(c, kCGTextStroke);
self.textColor = [UIColor blackColor];
[super drawTextInRect:rect];
CGContextSetTextDrawingMode(c, kCGTextFill);
self.textColor = textColor;
self.shadowOffset = CGSizeMake(0, 0);
[super drawTextInRect:rect];
self.shadowOffset = shadowOffset;
}
I successfully used this as a good template to subclass my UILabels, and now I would say I have a fair understanding on subclassing.
What I would like to do is use this subclass as the UILabel part of a UIButton so that the text within my buttons have a matching black outline.
Any help or even just being pointed in the right direction would be greatly appreciated.
Thanks
Dave
Why not just subclass UIButton, and then within that subclass make the same changes you made in your UILabel subclass to the button's label property. Basically you would do everything the exact same way, except all of your changes would refer to self.titleLabel instead of just self.
I am following Brad's answer to apply glow effect in my CALayer text.
Here is my code:
- (void)drawLayer:(CALayer *)theLayer inContext:(CGContextRef)context
{
UIGraphicsPushContext(context);
UIFont *font = [UIFont fontWithName:#"Verdana" size:11.0f];
CGRect rect = CGRectMake(theLayer.bounds.origin.x + 5, theLayer.bounds.origin.y + 5, theLayer.bounds.size.width - 10, theLayer.bounds.size.height - 10);
NSString * textToWrite = #"Some text";
UIColor *color = [ UIColor colorWithRed: (100.0f) green: (50.0) blue:(200.0f) alpha: 1.0f ];
CGContextSetFillColorWithColor(context, color.CGColor); //this has no effect!!!
CGContextSetShadowWithColor(context, CGSizeMake(0.0, 0.0), 2.0f, [UIColor greenColor].CGColor);
[textToWrite drawInRect:rect withFont:font
lineBreakMode:UILineBreakModeWordWrap alignment:UITextAlignmentLeft];
UIGraphicsPopContext();
}
I am getting a decent green glow here. However I want the text to have its own color too, apart from glow. For this I am using color variable here, along with CGContextSetFillColorWithColor. But it seems to have NO effect. The text seems white, with green glow. I want text with main color = color and glow=green.
What should I do?
I'm confused by your color... I think when declaring red green and blue in objective-c you set values that are up to 1.0 being the maximum (like you did with alpha) so when you give them their true 255 hex value you then divide by 255. Your color should be white since all 3 values are so far above the maximum... Maybe I'm wrong though first try these two codes...
Replace your current FillColorWithColor code with this:
[[UIColor colorWithCGColor:color] set];
(or maybe this...)
[[UIColor colorWithCGColor:color.CGColor] set];
If they don't work then try them while also changing your color code to this:
UIColor *color = [ UIColor colorWithRed: (100.0f/255.0f) green: (50.0f/255.0f) blue:(200.0f/255.0f) alpha: 1.0f ];
I'm drawing text in -drawRect with this method:
[someText drawInRect:rect withFont:font lineBreakMode:someLineBreakMode alignment:someAlignment];
I just want to draw the outline but not the fill!
I've found that I can set CGContextSetFillColorWithColor and just provide an fully transparent color. But I fear this has bad performance impact because probably it does all the heavy drawing work behind the scenes with a transparent color.
Is there a way to just disable the fill-drawing if only outline-drawing is wanted?
Have you tried using kCGTextFillStroke? This might work easily. To use it, just override drawTextInRect
- (void)drawTextInRect:(CGRect)rect {
CGSize shadowOffset = self.shadowOffset;
UIColor *textColor = self.textColor;
CGContextRef c = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(c, 1);
CGContextSetLineJoin(c, kCGLineJoinRound);
CGContextSetTextDrawingMode(c, kCGTextStroke);
self.textColor = [UIColor whiteColor];
[super drawTextInRect:rect];
CGContextSetTextDrawingMode(c, kCGTextFill);
self.textColor = textColor;
self.shadowOffset = CGSizeMake(0, 0);
[super drawTextInRect:rect];
self.shadowOffset = shadowOffset;
}
EDIT: This answer also appears in a previous incarnation of this question: How do I make UILabel display outlined text?
I have a main view with a picture on it.
I am trying to add a subview with [self.view addSubview:view2]; but I want the view2 background to be transparent. Have tried opaque=no and background color to clearcolor and also tried to subclass a uiview and rewrite the drawrect with:
#import "TransparentView.h"
#implementation TransparentView
- (id)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame]) {
[self setBackgroundColor:[UIColor clearColor]];
self.opaque=NO;
self.clearsContextBeforeDrawing=YES;
}
return self;
}
- (void)drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextClearRect(context, rect);
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
CGContextFillRect(context, rect);
}
#end
But still doesn't display the background of the subview transparent... any ideas?
Try:
view.backgroundColor = [UIColor colorWithWhite:0.0 alpha:0.0];
view.opaque = NO;
Is the view being loaded from a nib file? If so, the -initWithFrame: won't be called; -initWithCoder: will be called instead. A better place to do this initialization might be in -viewDidLoad. But setting the background color to [UIColor clearColor] should definitely do the trick.
Try coloring the subview's background with a 0.0 for Alpha. That should make it completely transparent.
Something like this:
UIColor *myUIColor = [UIColor colorWithRed: 1.0 green: 1.0 blue: 1.0 alpha:0.0];
In the function
- (void)drawRect:(CGRect)rect
try to update
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
to
const CGFloat BACKGROUND_OPACITY = 0.85; //Note: update this value to what you need
CGContextSetRGBFillColor(context, 1, 1, 1, BACKGROUND_OPACITY); // You can change 1,1,1 to the needed values
This link might help you
http://www.cocoawithlove.com/2009/04/showing-message-over-iphone-keyboard.html
I've had some cases where ... addSubview:clearView] seemed to reset the background color of clearView (WTF!) to something not clear. I added a
[clearView setBackgroundColor:nil];
somewhere after that and it seemed to help.
I know soft shadows are not supported by the UILabel out of the box, on the iPhone. So what would be the best way to implement my own one?
EDIT:
Obviously I will subclass the UILabel and draw in the -drawRect:
My question is, how do I get the contents of the label as graphics and draw around them, blur them etc...
EDIT 2:
I returned to this question about a year later. In the meantime I've built a class that allows you to easily add soft shadow to a label and tweak it's radius etc and also to draw gradients on the text itself. You can find it on GitHub: https://github.com/doukasd/iOS-Components/tree/master/Views
As of 3.2 there is direct support for shadows in the SDK.
label.layer.shadowColor = [label.textColor CGColor];
label.layer.shadowOffset = CGSizeMake(0.0, 0.0);
#import <QuartzCore/QuartzCore.h> and play with some parameters:
label.layer.shadowRadius = 3.0;
label.layer.shadowOpacity = 0.5;
And, if you find your shadow clipped by the label bounds:
label.layer.masksToBounds = NO;
finally set
label.layer.shouldRasterize = YES;
I advise you to use the shadowColor and shadowOffset properties of UILabel:
UILabel* label = [[UILabel alloc] init];
label.shadowColor = [UIColor whiteColor];
label.shadowOffset = CGSizeMake(0,1);
This answer to this similar question provides code for drawing a blurred shadow behind a UILabel. The author uses CGContextSetShadow() to generate the shadow for the drawn text.
Additionally to IIDan's answer:
For some purposes it is necessary to set
label.layer.shouldRasterize = YES
I think this is due to the blend mode that is used to render the shadow. For example I had a dark background and white text on it and wanted to "highlight" the text using a black shadowy glow. It wasn't working until I set this property.
Apply the (soft) shadow on the view's layer, like this:
UILabel *label = [[UIabel alloc] init];
label.layer.shadowColor = [[UIColor whiteColor] CGColor];
label.layer.shadowOpacity = 1.0;
To keep things up to date: Creating the shadow in Swift is as easy as that:
Import the QuartzCore Framework
import QuartzCore
And set the shadow attributes to your label
titleLabel.shadowColor = UIColor.blackColor()
titleLabel.shadowOffset = CGSizeMake(0.0, 0.0)
titleLabel.layer.shadowRadius = 5.0
titleLabel.layer.shadowOpacity = 0.8
titleLabel.layer.masksToBounds = false
titleLabel.layer.shouldRasterize = true
_nameLabel = [[UILabel alloc] initWithFrame:CGRectZero];
_nameLabel.font = [UIFont boldSystemFontOfSize:19.0f];
_nameLabel.textColor = [UIColor whiteColor];
_nameLabel.backgroundColor = [UIColor clearColor];
_nameLabel.shadowColor = [UIColor colorWithWhite:0 alpha:0.2];
_nameLabel.shadowOffset = CGSizeMake(0, 1);
i think you should use the [UIColor colorWithWhite:0 alpha:0.2] to set the alpha value.
I tried almost all of these techniques (except FXLabel) and couldn't get any of them to work with iOS 7. I did eventually find THLabel which is working perfectly for me. I used THLabel in Interface Builder and setup User Defined Runtime Attributes so that it's easy for a non programmer to control the look and feel.
https://github.com/MuscleRumble/THLabel
This like a trick,
UILabel *customLabel = [[UILabel alloc] init];
UIColor *color = [UIColor blueColor];
customLabel.layer.shadowColor = [color CGColor];
customLabel.layer.shadowRadius = 5.0f;
customLabel.layer.shadowOpacity = 1;
customLabel.layer.shadowOffset = CGSizeZero;
customLabel.layer.masksToBounds = NO;
I wrote a library that provides a UILabel subclass with soft shadow support and a bunch of other effects:
https://github.com/nicklockwood/FXLabel
In Swift 3, you can create an extension:
import UIKit
extension UILabel {
func shadow() {
self.layer.shadowColor = self.textColor.cgColor
self.layer.shadowOffset = CGSize.zero
self.layer.shadowRadius = 3.0
self.layer.shadowOpacity = 0.5
self.layer.masksToBounds = false
self.layer.shouldRasterize = true
}
}
and use it via:
label.shadow()
Subclass UILabel, as stated, then, in drawRect:, do [self drawTextInRect:rect]; to get the text drawn into the current context. Once it is in there, you can start working with it by adding filters and whatnot. If you want to make a drop shadow with what you just drew into the context, you should be able to use:
CGContextSetShadowWithColor()
Look that function up in the docs to learn how to use it.
As of iOS 5 Apple provides a private api method to create labels with soft shadows.
The labels are very fast: I'm using dozens at the same time in a series of transparent views and there is no slowdown in scrolling animation.
This is only useful for non-App Store apps (obviously) and you need the header file.
$SBBulletinBlurredShadowLabel = NSClassFromString("SBBulletinBlurredShadowLabel");
CGRect frame = CGRectZero;
SBBulletinBlurredShadowLabel *label = [[[$SBBulletinBlurredShadowLabel alloc] initWithFrame:frame] autorelease];
label.backgroundColor = [UIColor clearColor];
label.textColor = [UIColor whiteColor];
label.font = [UIFont boldSystemFontOfSize:12];
label.text = #"I am a label with a soft shadow!";
[label sizeToFit];
While it's impossible to set a blur radius directly on UILabel, you definitely could change it by manipulating CALayer.
Just set:
//Required properties
customLabel.layer.shadowRadius = 5.0 //set shadow radius to your desired value.
customLabel.layer.shadowOpacity = 1.0 //Choose an opacity. Make sure it's visible (default is 0.0)
//Other options
customLabel.layer.shadowOffset = CGSize(width: 10, height: 10)
customLabel.layer.shadowColor = UIColor.black.cgColor
customLabel.layer.masksToBounds = false
What I hope will help someone and other answers failed to clarify is that it will not work if you also set UILabel Shadow Color property directly on Interface Builder while trying to setup .layer.shadowRadius.
So if setting label.layer.shadowRadius didn't work, please verify Shadow Color for this UILabel on Interface Builder. It should be set to default. And then, please, if you want a shadow color other than black, set this color also through .layer property.
Subclass UILabel, and override -drawInRect: