How to draw multiple UIBezierPath with different c

问题:

I would like to draw multiple UIBezierPath in a UIView with different stroke and fill color.

Here is the code

- (void)drawRect:(CGRect)rect {

    context = UIGraphicsGetCurrentContext();

    [[UIColor grayColor] setFill]; 
    [[UIColor greenColor] setStroke];

    UIBezierPath *aPath = [[UIBezierPath alloc] init]; 
    [aPath moveToPoint:CGPointMake(227,34.25)];
    [aPath addLineToPoint:CGPointMake(298.25,34.75)];
    [aPath addLineToPoint:CGPointMake(298.5,82.5)];
    [aPath addLineToPoint:CGPointMake(251,83)];
    [aPath addLineToPoint:CGPointMake(251,67.5)];
    [aPath addLineToPoint:CGPointMake(227.25,66.75)];   
    [aPath closePath]; 
    aPath.lineWidth = 2;
    [aPath fill]; 
    [aPath stroke];

    UIBezierPath *aPath2 = [[UIBezierPath alloc] init];
    [aPath2 moveToPoint:CGPointMake(251.25,90.5)];
    [aPath2 addLineToPoint:CGPointMake(250.75,83.25)];
    [aPath2 addLineToPoint:CGPointMake(298.5,83)];
    [aPath2 addLineToPoint:CGPointMake(298.5,90.25)];
    [aPath2 closePath];
    aPath2.lineWidth = 2;
    [aPath2 fill]; 
    [aPath2 stroke];
    [paths addObject:aPath2];

The problem is that the stroke and the fill color are set on the current context. Is it possible to draw different UIBezierPath with different colors in the same CGContextRef?

Or I have to draw each UIBezierPath in separate UIView?

回答1:

You should add

[desiredStrokeColor setStroke];
[desiredFillColor setFill];

indicating that these are the new colors that have to used further on in this context. You should do this before every time you call a

[aNewPath fill];
[aNewPath stroke];

so that the paths be drawn with those colors.

No need to use a new view for each bezier path.

回答2:

use this

int count = 0;
for(UIBezierpath *_paths in pathArray)
{
   UIColor *_color = [delegate1.colorArray objectAtIndex:q];
   [_color setStroke];
   [_path strokeWithBlendMode:kCGBlendModeNormal alpha:1.0]; 
   count++;
}

In touch began store your paths and colors in two arrays and use them in drawrect like above.

回答3:

Just define a UIColor *setStroke; in .h file and set this strokeColor object before you call [myPath strokeWithBlendMode:kCGBlendModeNormal alpha:1.0];

 - (void)drawRect:(CGRect)rect
    {
        [strokeColor setStroke]; // this method will choose the color from the receiver color object (in this case this object is :strokeColor)
        for(UIBezierPath *_path in pathArray)
            [myPath strokeWithBlendMode:kCGBlendModeNormal alpha:1.0];
    }

    #pragma mark - Touch Methods
    -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
    {
        myPath=[[UIBezierPath alloc]init];
        myPath.lineWidth = currentSliderValue;

        UITouch *mytouch=[[touches allObjects] objectAtIndex:0];
        [myPath moveToPoint:[mytouch locationInView:self]];
        [pathArray addObject:myPath];
    }
    -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
    {
        UITouch *mytouch=[[touches allObjects] objectAtIndex:0];
        [myPath addLineToPoint:[mytouch locationInView:self]];
        [self setNeedsDisplay];

    }