上图表示红点，我喜欢加入这些点。
我喜欢在两点之间画一条线，我在 ImageView 中有图像，我喜欢标记图像的某些部分以指示该点，使用触摸事件我放置了点
-(void) drawRect:(CGRect)rect
{
if([pointarray count]==4)
{
float firstpointx= [[pointarray objectAtIndex:0]floatValue];
float firstpointy= [[pointarray objectAtIndex:1]floatValue];
float secondpointx= [[pointarray objectAtIndex:2]floatValue];
float secondpointy= [[pointarray objectAtIndex:3]floatValue];
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetStrokeColorWithColor(ctx, [UIColor blueColor].CGColor);
CGContextSetLineWidth(ctx, 2.0);
CGContextMoveToPoint(ctx, firstpointx, firstpointy);///move to ur first dot
CGContextAddLineToPoint(ctx, secondpointx, secondpointy);//add line from first dot to second dot
CGContextSetLineCap(ctx, kCGLineCapRound);
CGContextStrokePath(ctx);
[pointarray removeAllObjects];//remove first two points from ur array so that next line is not drawn in continuous with previous line
}
}
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
pointarray=[[NSMutableArray alloc]init];
CGPoint curPoint = [[touches anyObject] locationInView:self.view];
[pointarray addObject:[NSNumber numberWithFloat:curPoint.x]];
[pointarray addObject:[NSNumber numberWithFloat:curPoint.y]];
NSLog(@"the point array is %@",pointarray);
[self.view setNeedsDisplay]; // calls drawRectMethod
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
if ([touch tapCount] == 2) {
imageView.image = nil;
return;
}
if(!mouseSwiped) {
UIGraphicsBeginImageContext(self.view.frame.size);
[imageView.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1.0, 0.0, 0.0, 1.0);
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
CGContextStrokePath(UIGraphicsGetCurrentContext());
CGContextFlush(UIGraphicsGetCurrentContext());
imageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
}
之后我把我的点放在了这里如何连接这两个点，有人可以帮我吗!!!
最佳答案
使用以下代码它将起作用:-
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
mouseSwiped = NO;
UITouch *touch = [touches anyObject];
if ([touch tapCount] == 2) {
[drawImage setImage:[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"white" ofType:@"png"]]];
return;
}
lastPoint = [touch locationInView:self.view];
lastPoint.y -= 20;
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
mouseSwiped = YES;
UITouch *touch = [touches anyObject];
CGPoint currentPoint = [touch locationInView:self.drawImage];
currentPoint.y -= 20;
NSLog(@"current Point is x: %d, y: %d",currentPoint.x,currentPoint.y);
UIGraphicsBeginImageContext(self.drawImage.frame.size);
[drawImage.image drawInRect:CGRectMake(0, 0, self.drawImage.frame.size.width, self.drawImage.frame.size.height)];
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0, 0.5, 0.6, 1.0);
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y);
CGContextStrokePath(UIGraphicsGetCurrentContext());
drawImage.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
lastPoint = currentPoint;
}
随意问..
关于iphone - 在iphone的两点之间画线？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/8208469/