I want to draw line between to imageviews (like linking the images..) in UIView. I have used
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);
CGContextSetLineWidth(context, 2.0);
CGContextMoveToPoint(context, 0,0); //start at this point
CGContextAddLineToPoint(context, 20, 20); //draw to this point
CGContextStrokePath(context);
But here, my context is null. I dono whether i have to import any framework or import any headers. Any suggestion or sample will be appreciated.
Thanks in advance.
The very easy way is use label with height 1.:)
UILabel *seperator=[[UILabel alloc]initWithFrame:CGRectMake(0, 53, 233, 1)];
seperator.backgroundColor=[UIColor redColor];
[loginView addSubview:seperator];
UIGraphicsBeginImageContext(image_signature.image.size);
[yourImageView.image drawInRect:CGRectMake(0, 0, yourImageView.image.size.width, yourImageView.image.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 2.0);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0, 0.0, 0.0, 1.0);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), 0, 0);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), 20, 20);
CGContextStrokePath(UIGraphicsGetCurrentContext());
[yourImageView setImage:UIGraphicsGetImageFromCurrentImageContext()];
UIGraphicsEndImageContext();
...and "yourImageView" is an imageview where you will draw the line. I suggest you to draw the line on each upper imageview, at the very bottom, it's an option.
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetRGBStrokeColor(context, 1.0, 1.0, 1.0, 1.0);
CGContextSetLineWidth(context, 5.0);
CGContextMoveToPoint(context, 90, 90.0);
CGContextAddLineToPoint(context, 120.0, 150.0);
CGContextStrokePath(context);
Related
My line of code:
UIColor *brushPattern=[[UIColor alloc]initWithPatternImage:[UIImage imageNamed:#"Frame-1#2x.png"]];
CGContextSetStrokeColorWithColor(UIGraphicsGetCurrentContext(),brushPattern.CGColor);
Image pattern
url
Which does not draw like brush pattern whereas it fill pattern in UIView
I have used the following code for the same
At ViewDidLoad or Where ever your going to start the assign this
patternColor = [UIColor colorWithPatternImage:image]
This will resolve your memory issues and below code willhelp you
UIGraphicsBeginImageContextWithOptions(view.frame.size, NO, [[UIScreen mainScreen] scale]);
CGContextRef context = UIGraphicsGetCurrentContext();
[view.image drawInRect:CGRectMake(0, 0, view.frame.size.width, view.frame.size.height)];
CGContextSetInterpolationQuality(context, kCGInterpolationHigh);
CGContextSetLineCap(context, kCGLineCapRound);
CGContextSetLineWidth(context, 10);
CGContextSetStrokeColorWithColor(UIGraphicsGetCurrentContext(), patternColor.CGColor);
CGContextSetBlendMode(context, kCGBlendModeNormal);
CGContextBeginPath(context);
CGContextMoveToPoint(context, lastPoint.x, lastPoint.y);
CGContextAddLineToPoint(context, currentPoint.x, currentPoint.y);
CGContextStrokePath(context);
UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
I want to draw a curved line with arrow between two points using the Quartz Core framework in an iPhone Application. How to do that or any what classes are available to do that ?
You can change the co-ordinates as you want
- (void)drawRect:(CGRect)rect {
//DRAW CURVE
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextMoveToPoint(context, 100, 100);
CGContextAddArcToPoint(context, 100,200, 300,200, 100);
CGContextStrokePath(context);
//DRAW LINE
CGContextSetLineWidth(context, 2.0);
CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB();
CGFloat components[] = {0.0, 0.0, 1.0, 1.0};
CGColorRef color = CGColorCreate(colorspace, components);
CGContextSetStrokeColorWithColor(context, color);
CGContextMoveToPoint(context, 0, 0);
CGContextAddLineToPoint(context, 300, 400);
CGContextStrokePath(context);
CGColorSpaceRelease(colorspace);
CGColorRelease(color);
}
i want to erase image in view (like erase drawing with Eraser).i did if view frame is 0,0,320,480 ,but i worry if the view frame has different size:
here my code:
UIGraphicsBeginImageContext(self.view.frame.size);
[myImageView.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(),kCGImageAlphaNone);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 10);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1, 0, 0, 10);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), point.x, point.y);
//this line code for erasing select the part of the image
CGContextClearRect (UIGraphicsGetCurrentContext(), CGRectMake(point.x, point.y, 30, 30));
//End the code
CGContextStrokePath(UIGraphicsGetCurrentContext());
myImageView.image = UIGraphicsGetImageFromCurrentImageContext();
Try the below code ..
UIGraphicsBeginImageContext(self.frame.size);
[imageView.image drawInRect:CGRectMake(0, 0, imageView.frame.size.width, imageView.frame.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 30.0);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1.0, 1.0, 1.0, 1.0);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastTouch.x, lastTouch.y);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y);
CGContextStrokePath(UIGraphicsGetCurrentContext());
imageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
IS it possible to draw line with special shape for example like dotted(China Point) ? i draw line with below code
UIGraphicsBeginImageContext(self.view.frame.size);
[drawImage.image drawInRect:CGRectMake(0, 0, 320, 480)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.867, 0.867, 0.867, 1.0);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), startPoint.x, startPoint.y);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), endPoint.x, endPoint.y);
CGContextStrokePath(UIGraphicsGetCurrentContext());
CGContextFlush(UIGraphicsGetCurrentContext());
drawImage.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Maybe CGContextSetLineDash is what you want.
It sets the pattern for dashed lines in a graphics context.
void CGContextSetLineDash (
CGContextRef c,
CGFloat phase,
const CGFloat lengths[],
size_t count
);
This example draws a line with circles (diameter: 20 points, distance: 40 points):
CGContextSetLineWidth(context, 20.0);
CGFloat dash[] = {0.0, 40.0};
CGContextSetLineCap(context, kCGLineCapRound);
CGContextSetLineDash(context, 0.0, dash, 2);
CGContextMoveToPoint(context, 10.0, 30.0);
CGContextAddLineToPoint(context, 310.0, 30.0);
CGContextStrokePath(context);
Anyone have any idea why CGContextFillPath won't work in the code snippet below? I'm using the following code to draw to a UIImageView. It's stroking the path correctly, but ignoring CGContextFillPath.
UIGraphicsBeginImageContext(self.frame.size);
[drawingView.image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0);
CGContextSetAllowsAntialiasing(UIGraphicsGetCurrentContext(), YES);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1.0, 0.0, 0.0, 1.0);
CGContextSetRGBFillColor(UIGraphicsGetCurrentContext(), 1.0, 0.0, 0.0, 1.0);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), firstMovedTouch.x, firstMovedTouch.y);
CGContextStrokePath(UIGraphicsGetCurrentContext());
CGContextFillPath(UIGraphicsGetCurrentContext());
drawingView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
To solve this problem, use the following code:
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetRGBStrokeColor(context, 0.0, 0.0, 0.0, 1.0);
CGContextSetRGBFillColor(context, 0.0, 0.0, 0.0, 1.0);
CGContextSetLineJoin(context, kCGLineJoinRound);
CGContextSetLineWidth(context, 8.0);
CGMutablePathRef pathRef = CGPathCreateMutable();
/* do something with pathRef. For example:*/
CGPathMoveToPoint(pathRef, NULL, x, y);
CGPathAddLineToPoint(pathRef, NULL, x, y+100);
CGPathAddLineToPoint(pathRef, NULL, x+100, y+100);
CGPathAddLineToPoint(pathRef, NULL, x+100, y);
CGPathCloseSubpath(pathRef);
CGContextAddPath(context, pathRef);
CGContextFillPath(context);
CGContextAddPath(context, pathRef);
CGContextStrokePath(context);
CGPathRelease(pathRef);
I believe that the best way to stroke and fill your path is to add the following line of code after you've finished setting up your path:
CGContextDrawPath(myContext, kCGPathFillStroke);
I had the same trouble. I found that you can not use
CGContextStrokePath( UIGraphicsGetCurrentContext() )
CGContextFillPath( UIGraphicsGetCurrentContext() )
consecutively: the latter will not work because after committing the stroke on the path, the path is removed from the context.
So, I used the same path twice; one for strokeļ¼the other for fill.
// ... create a path of CGMutablePathRef ....
CGContextSaveGState( context );
//....fill the path .....
CGContextRestoreGState( context );
CGContextSaveGState ( context );
//....stroke the path .....
CGContextRestoreGState( context );
CFRelease( path );
I think you need to call CGContextClosePath before you can fill the path. I am not sure what you are trying to draw, but CGContextFillPath will fill the area inside the path and I only see single line here.