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underline text in UIlabel
Can any one provide a code to show me how to underline text in UILabel? In Interface Builder I underline the UILabel text but it's not working.
You can inheritate UILabel and draw a line yourself in drawTextInRec
you need to implement the drawRect: method of your UIView inherited class.
- (void)drawRect:(CGRect)rect
{
// Get the Render Context
CGContextRef ctx = UIGraphicsGetCurrentContext();
// Measure the font size, so the line fits the text.
// Could be that "titleLabel" is something else in other classes like UILable, dont know.
// So make sure you fix it here if you are enhancing UILabel or something else..
CGSize fontSize =[self.titleLabel.text sizeWithFont:self.titleLabel.font
forWidth:self.bounds.size.width
lineBreakMode:UILineBreakModeTailTruncation];
// Get the fonts color.
const float * colors = CGColorGetComponents(self.titleLabel.textColor.CGColor);
// Sets the color to draw the line
CGContextSetRGBStrokeColor(ctx, colors[0], colors[1], colors[2], 1.0f); // Format : RGBA
// Line Width : make thinner or bigger if you want
CGContextSetLineWidth(ctx, 1.0f);
// Calculate the starting point (left) and target (right)
float fontLeft = self.titleLabel.center.x - fontSize.width/2.0;
float fontRight = self.titleLabel.center.x + fontSize.width/2.0;
// Add Move Command to point the draw cursor to the starting point
CGContextMoveToPoint(ctx, fontLeft, self.bounds.size.height - 1);
// Add Command to draw a Line
CGContextAddLineToPoint(ctx, fontRight, self.bounds.size.height - 1);
// Actually draw the line.
CGContextStrokePath(ctx);
// should be nothing, but who knows...
[super drawRect:rect];
}
Taken form iPhone Programming how to underline UILabel
You could also inherit UILabel . See the belwo SO post, which does exactly the same.
Underline text in UIlabel
Related
I'm replacing the background view of a UITableViewCell with my own custom subclass of UIView, in which I override the drawRect method with my own, which creates a multi-colored and changing background.
The problem is that when the TableViewCell is selected, the graphics under are completely hidden and it looks odd. I need to create a custom selectedBackgroundView in order to fix this. The problem is that that view needs to create a blue gradient tint over the graphics already there, and I don't know how to draw a CGRect or something similar that is partially transparent.
// Write this In your - (void)drawRect:(CGRect)rect
// To draw semi transparent Square
// Create Current Context To Draw
CGContextRef context = UIGraphicsGetCurrentContext();
UIBezierPath *square = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, 100, 100)];
// following method will fill red color with alpha 0.4 last one in parameter list
// first 3 are Red, Green and Blue Respectively.
CGContextSetRGBFillColor(context, 1, 0, 0, 0.4);
[square fill];
[square stroke];
Is there appeared easy way to underline text in iOS 4 ?? In IB maybe ? Thanks in advance...
As far as I know you cannot underline text.
You can "fake" it though by (for example) placing an UImageView or a regular View just underneath with the same color as your text. You can use strike-through etc, but cannot underline.
Edit:
You could use this approach to underline your UILabel though. You could namely use a custom UILabel. So you could create some class like CUILabel that inherits UILabel and replace its drawRect method in the #implementation section with the following:
- (void)drawRect:(CGRect)rect {
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetRGBStrokeColor(ctx, 0.0f/255.0f, 0.0f/255.0f, 255.0f/255.0f, 1.0f); // Your underline color
CGContextSetLineWidth(ctx, 1.0f);
UIFont *font = [UIFont systemFontOfSize:16.0f];
CGSize constraintSize = CGSizeMake(MAXFLOAT, MAXFLOAT);
CGSize labelSize;
labelSize = [self.text sizeWithFont:font constrainedToSize:constraintSize lineBreakMode:UILineBreakModeWordWrap];
CGContextMoveToPoint(ctx, 0, self.bounds.size.height - 1);
CGContextAddLineToPoint(ctx, labelSize.width + 10, self.bounds.size.height - 1);
CGContextStrokePath(ctx);
[super drawRect:rect];
}
Just subclass UILabel and in drawRect after you draw your text just draw an simple line under the text. Take a look at StrikeUILabel it have some bugs in it but you can start from that class.
NSMutableAttributedString/NSAttributedString allows you to create text with various rich attributes like font,color,type styles (including underline). For generic details follow this link..
Introduction to Attributed String Programming Guide
Specific to underline of text, this link may help..
Changing an Attributed String
Sometimes i prefer to use UILabel as Underline with background of Underline color, no text, height 1 or 2 pixel and width as equal to Text to be underline...
I was wondering if there is a standard method in iOS to produce the numbered bubble icon for unread messages as the ones used in mail for iphone and mac.
I'm not talking about the red dots on the application item which is done with badgevalue but about the blue bubble beside the mailboxes.
Of course one can do it manually using coregraphics but it's harder to match the dimensions and color of the standard ones used in mail etc.
here are three ways to do this, in order of difficulty..
screen shot your mail app from your iphone, send the image into photoshop, extract the blue dot and use it as an image in your app. To use it in a tableviewcell, you just set the imageView.image = [UIImage imageName:#"blueDot.png"];
same as #1, except save the image as a grayscale, this way you can use Quartz and overlay your own colors on top of it. so you can make that dot any color you want. Very cool stuff.
Use Quartz to draw the whole thing. Its really not that hard. Let me know if you would like some code for that.
OK, twist my arm... here is the code to draw your own gradient sphere... from quartz.
Make a class that inherits from UIView. add the following code
static float RADIANS_PER_DEGREE=0.0174532925;
-(void) drawInContext:(CGContextRef) context
{
// Drawing code
CGFloat radius = self.frame.size.width/2;
CGFloat start = 0 * RADIANS_PER_DEGREE;
CGFloat end = 360 * RADIANS_PER_DEGREE;
CGPoint startPoint = CGPointMake(0, 0);
CGPoint endPoint = CGPointMake(0, self.bounds.size.height);
//define our grayscale gradient.. we will add color later
CGFloat cc[] =
{
.70,.7,.7,1, //r,g,b,a of color1, as a percentage of full on.
.4,.4,.4,1, //r,g,b,a of color2, as a percentage of full on.
};
//set up our gradient
CGGradientRef gradient;
CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
gradient = CGGradientCreateWithColorComponents(rgb, cc, NULL, sizeof(cc)/(sizeof(cc[0])*4));
CGColorSpaceRelease(rgb);
//draw the gray gradient on the sphere
CGContextSaveGState(context);
CGContextBeginPath(context);
CGContextAddArc(context, self.bounds.size.width/2, self.bounds.size.height/2, radius,start,end , 0);
CGContextClosePath(context);
CGContextClip(context);
CGContextAddRect(context, self.bounds);
CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, kCGGradientDrawsBeforeStartLocation);
CGGradientRelease(gradient);
//now add our primary color. you could refactor this to draw this from a color property
UIColor *color = [UIColor blueColor];
[color setFill];
CGContextSetBlendMode(context, kCGBlendModeColor); // play with the blend mode for difference looks
CGContextAddRect(context, self.bounds); //just add a rect as we are clipped to a sphere
CGContextFillPath(context);
CGContextRestoreGState(context);
}
- (void)drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
[self drawInContext:context];
}
If you want to use a graphic resource from iOS, you can find it using the UIKit-Artwork-Extractor tool. Extract everything to the desktop and find the one you want. For example, the red badge for notifications is called SBBadgeBG.png. I don't know which one you mean, so search for it yourself :P
This is what I did to use a badge, the procedure is exactly the same to show a bubble in a subview of your table:
// Badge is an image with 14+1+14 pixels width and 15+1+15 pixels height.
// Setting the caps to 14 and 15 preserves the original size of the sides, so only the pixel in the middle is stretched.
UIImage *image = [UIImage imageNamed:#"badge"];
self.badgeImage = [image stretchableImageWithLeftCapWidth:(image.size.width-1)/2 topCapHeight:(image.size.height-1)/2];
// what size do we need to show 3 digits using the given font?
self.badgeFont = [UIFont fontWithName:#"Helvetica-Bold" size:13.0];
CGSize maxStringSize = [[NSString stringWithString:#"999"] sizeWithFont:self.badgeFont];
// set the annotation frame to the max needed size
self.frame = CGRectMake(0,0,
self.badgeImage.size.width + maxStringSize.width,
self.badgeImage.size.height + maxStringSize.height);
and then override the method drawRect: of your view to paint the badge and the numbers inside:
- (void)drawRect:(CGRect)rect {
// get the string to show and calculate its size
NSString *string = [NSString stringWithFormat:#"%d",self.badgeNumber];
CGSize stringSize = [string sizeWithFont:self.badgeFont];
// paint the image after stretching it enough to acommodate the string
CGSize stretchedSize = CGSizeMake(self.badgeImage.size.width + stringSize.width,
self.badgeImage.size.height);
// -20% lets the text go into the arc of the bubble. There is a weird visual effect without abs.
stretchedSize.width -= abs(stretchedSize.width *.20);
[self.badgeImage drawInRect:CGRectMake(0, 0,
stretchedSize.width,
stretchedSize.height)];
// color of unread messages
[[UIColor yellowColor] set];
// x is the center of the image minus half the width of the string.
// Same thing for y, but 3 pixels less because the image is a bubble plus a 6px shadow underneath.
float height = stretchedSize.height/2 - stringSize.height/2 - 3;
height -= abs(height*.1);
CGRect stringRect = CGRectMake(stretchedSize.width/2 - stringSize.width/2,
height,
stringSize.width,
stringSize.height);
[string drawInRect:stringRect withFont:badgeFont];
}
I would like to create a view like the notes app on iPhone and therefor need the view to have ruled lines as per the notes app, I have done this in windows where you need to get the font metrics and then draw the lines onto the device context, has anyone done this in the UITextView if so some help would be appriciated
Subclass UITextView. Override -drawRect:
- (void)drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetStrokeColorWithColor(context, self.lineColor.CGColor);
CGContextSetLineWidth(context, self.lineWidth);
CGFloat strokeOffset = (self.lineWidth / 2);
CGFloat rowHeight = self.font.lineHeight;
if (rowHeight > 0) {
CGRect rowRect = CGRectMake(self.contentOffset.x, - self.bounds.size.height, self.contentSize.width, rowHeight);
while (rowRect.origin.y < (self.bounds.size.height + self.contentSize.height)) {
CGContextMoveToPoint(context, rowRect.origin.x + strokeOffset, rowRect.origin.y + strokeOffset);
CGContextAddLineToPoint(context, rowRect.origin.x + rowRect.size.width + strokeOffset, rowRect.origin.y + strokeOffset);
CGContextDrawPath(context, kCGPathStroke);
rowRect.origin.y += rowHeight;
}
}
}
When you init the text view, be sure to set the contentMode to UIViewContentModeRedraw. Otherwise the lines won't scroll with the text.
self.contentMode = UIViewContentModeRedraw;
This isn't perfect. Ideally you should just draw into the rect that's passed. But I was lazy and this worked for my needs.
I think this works OK but I feel it has been hacked and I do not fully undestand the mechanism of the UITextView class;
first you must add the following to your delegate to force a redraw on scrolling
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
// NSLog(#"scrollViewDidScroll The scroll offset is ---%f",scrollView.contentOffset.y);
[noteText setNeedsDisplay];
}
then implement drawRect in the subclass as so
- (void)drawRect:(CGRect)rect {
// Drawing code
// Get the graphics context
CGContextRef ctx = UIGraphicsGetCurrentContext();
[super drawRect:rect];
// Get the height of a single text line
NSString *alpha = #"ABCD";
CGSize textSize = [alpha sizeWithFont:self.font constrainedToSize:self.contentSize lineBreakMode:UILineBreakModeWordWrap];
NSUInteger height = textSize.height;
// Get the height of the view or contents of the view whichever is bigger
textSize = [self.text sizeWithFont:self.font constrainedToSize:self.contentSize lineBreakMode:UILineBreakModeWordWrap];
NSUInteger contentHeight = (rect.size.height > textSize.height) ? (NSUInteger)rect.size.height : textSize.height;
NSUInteger offset = 6 + height; // MAGIC Number 6 to offset from 0 to get first line OK ???
contentHeight += offset;
// Draw ruled lines
CGContextSetRGBStrokeColor(ctx, .8, .8, .8, 1);
for(int i=offset;i < contentHeight;i+=height) {
CGPoint lpoints[2] = { CGPointMake(0, i), CGPointMake(rect.size.width, i) };
CGContextStrokeLineSegments(ctx, lpoints, 2);
}
}
Still worry about this Magic Number 6
Bob
You can try setting the backgroundColor of you textView using an image with ruled lines
textView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"RuledLinesPage.png"]];
Color with pattern image creates a tiled image if the area to be filled with the color is larger than the image. So you will have to make sure that the image size is correct size/tileable (I don't think 'tileable' is a real word but i hope you get what i mean). Also you will have to create the image with ruled lines to best match you textView's font.
Good Luck.
#lukya,
Your solution is bit messy as when we scroll the UITextView the text only scrolls leaving the lines (coming from the image) in its place.
A better solution would be to add subview to your text view where you have drawn the lines. You need to add an observer to the text view in order to track its change in content size as the text increase/decrease.
I need to create a custom UILabel to display some dynamic multiline text. The text color is white on a black background. But the background should only be visible right behind the text to simulate the effect of an selected text area.
I started with subclassing UILabel and overriding drawTextInRect to do my own drawings.
- (void) drawTextInRect:(CGRect)rect
{
/* do some custom drawings here */
[super drawTextInRect:rect];
}
So far i could not figure out a way to compute the text-bounds do draw my background into.
Does anybody now how do do this kind of stuff? Thanks a lot.
NSString has some additions in UIKit to allow for calculating the size used to render the string, given various parameters. You can use these methods to calculate the size the UILabel needs to render the string, and then resize the UILabel to precisely this size. Look in the documentation for a method called -sizeWithFont:, all of the other variations are listed there. Make sure you use the right method to match how your UILabel is configured.
There is one caveat here, which is that on iOS 4, there is a bug where these methods actually return a slightly different size than is actually used for drawing (at least for the system font on iPhone 4's [e.g. Helvetica Neue], I don't know if this bug affects any other fonts). Unfortunately the only workaround I know of is to switch to Core Text for all your text rendering, so you may just prefer to live with this bug (if it even affects you) until Apple pushes out a software update. This bug does affect Apple's own applications so there is plenty of precedent for not handling it.
Ok. Now after some input from stackoverflow i am using this code snippet to get the textbounds but it only works fine with single line text.
- (void) drawTextInRect:(CGRect)rect
{
CGFloat lineHeight = [self.text sizeWithFont:self.font].height;
CGSize testSize = CGSizeMake(320, lineHeight * self.numberOfLines);
CGSize textSize = [self.text sizeWithFont:self.font constrainedToSize:testSize lineBreakMode:self.lineBreakMode];
//NSLog(#"drawTextInRect lineHeight %f, width %f x height %f", lineHeight, textSize.width, textSize.height);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSaveGState(context);
CGContextSetRGBFillColor(context, 0.0, 0.0, 0.0, 1.0);
CGContextAddRect(context, CGRectMake(0, 0, textSize.width, textSize.height));
CGContextFillPath(context);
CGContextRestoreGState(context);
[super drawTextInRect:rect];
}
If i have multiline text i still need some code to compute the path-information of the text and not just the bounding rect so that i can use CGContextDrawPath to draw my background. Any thoughts on that? Thanks.