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POLag while drawing in ios7
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copied!<p>I am having an app in which I am doing some sketching on a view. </p> <p>So far, it was working fine until I installed <code>ios7</code>. </p> <p>My app uses touches moved method for recognizing the change of a movement. But when I draw a line, touches method gets called but line doesn't get updated until I touch ends in <code>ios7</code>.</p> <p>So there is a slight lag in drawing. </p> <p>It works fine on <code>ios6</code> and on <code>ios7</code> simulator but when i test it on a real <code>ios7</code> device, there is a lag in drawing algorithm.</p> <pre><code>- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { if (!isImageSelection) { mouseSwiped = NO; UITouch *touch = [touches anyObject]; if ( [touch view] != baseview) { lastPoint2 = [touch locationInView:self.viewDrawing2]; } } } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { if (!isImageSelection) { // NSLog(@"in image selection==%d touch moved ",isImageSelection ); mouseSwiped = YES; UITouch *touch = [touches anyObject]; // if (([touch view] != btnInkColor) || ([touch view] != btnPenSize) || ([touch view] != baseview)) { if ( [touch view] != baseview) { CGPoint currentPoint = [touch locationInView:self.viewDrawing]; if(isEraser) { // [[NSUserDefaults standardUserDefaults] floatForKey:@"strokeValue"]; UIGraphicsBeginImageContext(self.viewDrawing.frame.size); [imgDrawing.image drawInRect:CGRectMake(0, 0, self.viewDrawing.frame.size.width, self.viewDrawing.frame.size.height)]; CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineWidth(UIGraphicsGetCurrentContext(), stroke); //uncommented by prerak CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), red, green, blue, 1.0); CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeClear); CGContextBeginPath(UIGraphicsGetCurrentContext()); CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y); CGContextStrokePath(UIGraphicsGetCurrentContext()); imgDrawing.image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } else { float strokeT= [[NSUserDefaults standardUserDefaults] floatForKey:@"strokeValue"]; // NSLog(@"strokeT=%f",strokeT); UIGraphicsBeginImageContext(self.viewDrawing.frame.size); [imgDrawing.image drawInRect:CGRectMake(0, 0, self.viewDrawing.frame.size.width, self.viewDrawing.frame.size.height)]; // NSLog(@"STROKE %f",stroke); CGContextSetLineWidth(UIGraphicsGetCurrentContext(), strokeT); CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeCopy); float redT=[[NSUserDefaults standardUserDefaults] floatForKey:@"redvalue"]; float greenT= [[NSUserDefaults standardUserDefaults] floatForKey:@"greenvalue"]; float blueT= [[NSUserDefaults standardUserDefaults] floatForKey:@"bluevalue"]; // NSLog(@"red=%f",redT); // NSLog(@"green=%f",greenT); // NSLog(@"blue=%f",blueT); CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), redT, greenT, blueT, 1.0); CGContextSetRGBFillColor(UIGraphicsGetCurrentContext(), redT, greenT, blueT, 1.0); CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineJoin(UIGraphicsGetCurrentContext(), kCGLineJoinRound); CGContextBeginPath(UIGraphicsGetCurrentContext()); CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y); CGContextStrokePath(UIGraphicsGetCurrentContext()); imgDrawing.image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } lastPoint = currentPoint; } } } - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; //if (([touch view] != btnInkColor) || ([touch view] != btnPenSize) || ([touch view] != baseview)) { if ( [touch view] != baseview) { if (!isImageSelection) { if(!mouseSwiped) { if (isEraser) { UIGraphicsBeginImageContext(self.viewDrawing.frame.size); [imgDrawing.image drawInRect:CGRectMake(0, 0, self.viewDrawing.frame.size.width, self.viewDrawing.frame.size.height)]; CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineWidth(UIGraphicsGetCurrentContext(), stroke); // CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), red, green, blue, 1.0); CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeClear); CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextStrokePath(UIGraphicsGetCurrentContext()); CGContextFlush(UIGraphicsGetCurrentContext()); imgDrawing.image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } else { UIGraphicsBeginImageContext(self.viewDrawing.frame.size); [imgDrawing.image drawInRect:CGRectMake(0, 0, self.viewDrawing.frame.size.width, self.viewDrawing.frame.size.height)]; CGContextSetLineWidth(UIGraphicsGetCurrentContext(), stroke); CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeCopy); CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), red, green, blue, 1.0); CGContextSetRGBFillColor(UIGraphicsGetCurrentContext(), red, green, blue, 1.0); CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineJoin(UIGraphicsGetCurrentContext(), kCGLineJoinRound); CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextStrokePath(UIGraphicsGetCurrentContext()); CGContextFlush(UIGraphicsGetCurrentContext()); imgDrawing.image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } } } } } } </code></pre> <p>How can i solve this?</p>

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