- (void)drawRect:(CGRect)rect {
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSelectFont(context, "Arial", 24, kCGEncodingMacRoman);
CGContextShowTextAtPoint(context, 80, 80, "I am Rahul", 7);
}
I am trying to draw text as shown above "I am Rahul" but when i execute the code,
text gets shown, but it is inverted, why it is happening I am not getting !! help!!
You can use this code :
CGContextSetTextMatrix(context, CGAffineTransformMake(1.0,0.0, 0.0, -1.0, 0.0, 0.0));
This is easier:
- (void)drawRect:(CGRect)rect {
NSString* string = #"I am Rahul";
[string drawAtPoint:CGPointMake(80, 80)
withFont:[UIFont systemFontOfSize:24]];
}
Related
In iOS7 CGContextSelectFont is deprecated. Deprecation message says that I have to use Core Text, but I don't know which is the exact equivalent of this piece of code:
CGContextSelectFont(context, "Helvetica", kBarLabelSize, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 0, 0, 0, 1.0);
CGContextSetTextMatrix (context, CGAffineTransformMake(1.0, 0.0, 0.0, -1.0, 0.0, 0.0));
CGContextShowTextAtPoint(context, barX, barY, [#"Some text" cStringUsingEncoding:NSUTF8StringEncoding], [barValue length]);
I've been able to create the font with this code:
CFMutableAttributedStringRef attrStr = CFAttributedStringCreateMutable(kCFAllocatorDefault, 0);
CTFontRef font = CTFontCreateWithName(CFSTR("Helvetica"), kBarLabelSize, NULL);
CFAttributedStringSetAttribute(attrStr, CFRangeMake(0, CFAttributedStringGetLength(attrStr)), kCTFontAttributeName, font);
But now haw can I "draw" a text with this font into the context?
As best I can understand from your code, the exact equivalent is:
CGContextSetTextDrawingMode(context, kCGTextFill); // This is the default
[[UIColor blackColor] setFill]; // This is the default
[#"Some text" drawAtPoint:CGPointMake(barX, barY)
withAttributes:#{NSFontAttributeName:[UIFont fontWithName:#"Helvetica"
size:kBarLabelSize]
}];
Note that your calls to CGContextSetTextDrawingMode and CGContextSetRGBFillColor are setting the values to the defaults. Your call to CGContextSetTextMatrix is not needed when using UIKit drawing like this.
I have no idea what [barValue length] is here, however. I'm assuming that you simply incorrectly used this for the length of #"Some text". (length is not the number of bytes which is what you need. What you probably meant was [barValue lengthOfBytesUsingEncoding:NSUTF8StringEncoding]).
Note that UIKit string drawing (seen here) wraps Core Text.
I have found, at least in my case, the problem with the new NSString.drawAtPoint interface is that it may draw upside down, depending on how you are using the context.
An alternate is to use the Core Text methods, specifically the CTLine interface thusly:
NSDictionary *attribs = #{NSFontAttributeName:[UIFont fontWithName:#"Helvetica" size:14.0]};
NSAttributedString *fontStr = [[NSAttributedString alloc] initWithString:#"some text" attributes:attribs];
CTLineRef displayLine = CTLineCreateWithAttributedString( (__bridge CFAttributedStringRef)fontStr );
CGContextSetTextPosition( ctx, xPosition, yPosition );
CTLineDraw( displayLine, ctx );
CFRelease( displayLine );
You probably can use the following to replace it.
CGContextSetFont
CGContextSetFontSize
I am trying to do this:
so I am using this code:
[self.lblRound setOutlineColor:[UIColor colorWithRed:(68/255.0) green:(82/255.0) blue:(120/255.0) alpha:1]];
self.lblRound.drawOutline = YES;
but this is what i get:
I also did try this code:
lblRound.shadowColor = [UIColor colorWithRed:(68/255.0) green:(82/255.0) blue:(120/255.0) alpha:1];
lblRound.shadowOffset = CGSizeMake(0, 0);
I also did try to make another label with the needed color and to draw it behind the text, but if I am playing with the size of the text, it influence on the width of the all text.
How can I make the stroke thicker?
I can't use an image because I have a number in this text that should be variable.
Thanks
This is the solution:
- (void)drawRect:(CGRect)rect
{
UIFont *font=[UIFont fontWithName:#"VAGRoundedStd-Bold" size:40];
CGContextRef context = UIGraphicsGetCurrentContext();
string = lblRoundnumber;
CGSize fontWidth = [string sizeWithFont:font];
CGRect tempRect=rect;
tempRect.origin.x +=160-(fontWidth.width/2);
tempRect.origin.y +=high+42;
CGContextSetRGBStrokeColor(context, 68/255.0f, 82/255.0f, 120/255.0f, 1/1.0f);
CGContextSetRGBFillColor(context, 68/255.0f, 82/255.0f, 120/255.0f, 1/1.0f);
CGContextSetTextDrawingMode(context, kCGTextStroke);
CGContextSetLineWidth(context, 11);
[string drawInRect:tempRect withFont:font];
CGContextSetRGBFillColor(context, 1,1,1,1);
CGContextSetTextDrawingMode(context, kCGTextFill);
[string drawInRect:tempRect withFont:font];
}
I want to create UIImage of text.Is there any tutorial of something which could help me.I read many blog but all the blogs showing that how to create text on uiimage but I need uimage of written text. If somebody have any idea about this , please help me.Thank you very much.
hi you try this this....
i hope it will work for you
-(UIImage *)imageFromText:(NSString *)text withImage:(UIImage*)img{
// set the font type and size
UIFont *font = [UIFont systemFontOfSize:100.0];
CGSize size = [text sizeWithFont:font];
// check if UIGraphicsBeginImageContextWithOptions is available (iOS is 4.0+)
if (UIGraphicsBeginImageContextWithOptions != NULL)
UIGraphicsBeginImageContextWithOptions(size,NO,0.0);
else
// iOS is < 4.0
UIGraphicsBeginImageContext(size);
// optional: add a shadow, to avoid clipping the shadow you should make the context size bigger
//
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetShadowWithColor(ctx, CGSizeMake(0.0, 1.0), 5.0, [[UIColor blackColor] CGColor]);
CGContextSetBlendMode(ctx,kCGBlendModeNormal);
// CGContextSetFillColorWithColor(ctx, [UIColor whiteColor].CGColor);
CGContextSetFillColorWithColor(ctx, [UIColor colorWithPatternImage:img].CGColor);
/*NSLog(#"Rect %#",CGContextGetClipBoundingBox(ctx));
CGImageRef alphaMask = CGBitmapContextCreateImage(ctx);
CGContextClipToMask(ctx, CGContextGetClipBoundingBox(ctx), alphaMask);*/
// draw in context, you can use also drawInRect:withFont:
[text drawAtPoint:CGPointMake(0.0, 0.0) withFont:font];
// transfer image
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
the method call will be...
[self imageFromText:#"Booooooooom"];
Check this snippet of code, should work. You can freely change some of the parameters within function. Note that you must pass UIImage created somewhere else to this method.
//Add text to UIImage
-(UIImage *)addText:(UIImage *)img text:(NSString *)text1{
int w = img.size.width;
int h = img.size.height;
//lon = h - lon;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];// "05/05/09";
CGContextSelectFont(context, "Arial", 18, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 255, 255, 1);
//rotate text
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/4 ));
CGContextShowTextAtPoint(context, 4, 52, text, strlen(text));
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:imageMasked];
}
When I draw some text using CGContext, it is drawn mirrored.
I tried to apply some transformations, then it is draw well, but then the rest of the drawing and all coordinates seems to be draw bad.
I tried to save and restore the context, before and ater drawing the text (and aplying transformation), but that does not help.
How some text must be drawn onto a View using CGContext without affecting the rest of the drawing, nor the onscreen CGPoint coords for that text ?
Can you clarify what you mean as 'mirrored'? Here is some code for drawing some black text. It should not be 'mirrored'.
CGRect viewBounds = self.bounds;
CGContextTranslateCTM(ctx, 0, viewBounds.size.height);
CGContextScaleCTM(ctx, 1, -1);
CGContextSetRGBFillColor(ctx, 0.0, 1.0, 0.0, 1.0);
CGContextSetLineWidth(ctx, 2.0);
CGContextSelectFont(ctx, "Helvetica", 10.0, kCGEncodingMacRoman);
CGContextSetCharacterSpacing(ctx, 1.7);
CGContextSetTextDrawingMode(ctx, kCGTextFill);
CGContextShowTextAtPoint(ctx, 100.0, 100.0, "SOME TEXT", 9);
I think you have to reverse the text matrix :
CGAffineTransform transform = CGAffineTransformMake(1.0, 0.0, 0.0, -1.0, 0.0, 0.0);
CGContextSetTextMatrix(context, transform);
I am writing a simple practice. However, my text is flip upside down when I trying to use CGContext to put some string on the UIView, I am wondering why and how to change it into correct format.
Here is my code in the drawRect
char *string = "TEST";
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextBeginPath(context);
CGContextSelectFont (context,"Helvetica-Bold",12, kCGEncodingMacRoman);
CGContextShowTextAtPoint(context, 5, 5, string, strlen(string));
CGContextClosePath(context);
Thanx for your help.
CoreGraphics uses cartesian coordinates, so you need to translate your context before doing any drawing
CGContextRef context = UIGraphicsGetCurrentContext();
// transforming context
CGContextTranslateCTM(context, 0.0, rect.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
// your drawing code
Quartz2D has an inverted y axis - handy eh? If you are inside a drawRect method, you can use the following to flip the text over.
CGContextTranslateCTM(context, 0.0, rect.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
Another way is;
transform = CGAffineTransformMake(1.0,0.0,0.0,-1.0,0.0,0.0);
CGContextSetTextMatrix(context, transform);
Or on one line;
CGContextSetTextMatrix(context, CGAffineTransformMake(1.0,0.0, 0.0, -1.0, 0.0, 0.0));
Use the UIKit additions in NSString:
NSString *string = #"TEST";
[string drawAtPoint:CGPointMake(5, 5)
withFont:[UIFont boldSystemFontOfSize:12]];