Change UIBezierPath Colour when selected - ios

Question

I draw 3 squares in a - LayoutView
- (void)drawRect:(CGRect)rect
self.room1 = [UIBezierPath bezierPathWithRect:CGRectMake(81, 10, 60, 60)];
[self.normalColor setFill];
[self.room1 fill];
[[UIColor blackColor]setStroke];
self.room1.lineWidth = 1;
[self.room1 stroke];
then I find the correct UIBezierPath with
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"touch here");
UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInView:self];
if ([self.room1 containsPoint:touchPoint])
{
// do stuff
NSLog(#"room1 %#" , self.room1);
[[UIColor redColor] setFill];
[self.room1 fill];
[self setNeedsDisplay];
}
}
this is working I touch room 1 and the log print "room1"
But how do I change the colour of the room1 ?
At the moment I get an error
: CGContextSetFillColorWithColor: invalid context 0x0. This is a serious error. ...
thanks for your help.

Answer 1

One way to accomplish this, is to keep track of the selected state in the touchesBegan method, and keep all the fill and setFill statements inside drawRect. In the following example, I toggle the selected state with each touch inside the square which alternates the color between blue and red.
#interface RDView ()
#property (strong,nonatomic) UIBezierPath *room1;
#property (strong,nonatomic) UIColor *normalColor;
#property (strong,nonatomic) UIColor *selectedColor;
#property (nonatomic) BOOL isSelected;
#end
#implementation RDView
-(id)initWithCoder:(NSCoder *)aDecoder {
if (self = [super initWithCoder:aDecoder]) {
self.normalColor = [UIColor blueColor];
self.selectedColor = [UIColor redColor];
self.isSelected = NO;
}
return self;
}
- (void)drawRect:(CGRect)rect {
self.room1 = [UIBezierPath bezierPathWithRect:CGRectMake(81, 10, 60, 60)];
UIColor *colorToUse = (self.isSelected)? self.selectedColor : self.normalColor;
[colorToUse setFill];
[self.room1 fill];
[[UIColor blackColor]setStroke];
self.room1.lineWidth = 1;
[self.room1 stroke];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
CGPoint touchPoint = [touches.anyObject locationInView:self];
if ([self.room1 containsPoint:touchPoint]){
self.isSelected = ! self.isSelected;
[self setNeedsDisplay];
}
}