Draw part of a circle

Question

For an iPhone application I want to draw a circle, that is only for an x percentage filled.

Something like this:

Answer 1

Try this code in a UIView, Example "MyChartClass"...

- (void)drawRect:(CGRect)rect {
    int c=(int)[itemArray count];

    CGFloat angleArray[c];
    CGFloat offset;
    int sum=0;

    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetAllowsAntialiasing(context, false);
    CGContextSetShouldAntialias(context, false);

    for(int i=0;i<[itemArray count];i++) {
        sum+=[[itemArray objectAtIndex:i] intValue];
    }

    for(int i=0;i<[itemArray count];i++) {
        angleArray[i]=(float)(([[itemArray objectAtIndex:i] intValue])/(float)sum)*(2*3.14); 
        CGContextMoveToPoint(context, radius, radius);
        if(i==0)
            CGContextAddArc(context, radius, radius, radius, 0,angleArray[i], 0);
        else
            CGContextAddArc(context, radius, radius, radius,offset,offset+angleArray[i], 0);
        offset+=angleArray[i];

        CGContextSetFillColorWithColor(context, ((UIColor *)[myColorArray objectAtIndex:i]).CGColor);
        CGContextClosePath(context); 
        CGContextFillPath(context);

    }   
}

Implementation in your UIViewController

MyChartClass *myChartClass=[[MyChartClass alloc]initWithFrame:CGRectMake(0, 0, 200, 200)];
myChartClass.backgroundColor = [UIColor clearColor];
myChartClass.itemArray=[[NSArray alloc]initWithObjects:@"75",@"25", nil];
myChartClass.myColorArray=[[NSArray alloc]initWithObjects:[UIColor blackColor],[UIColor whiteColor], nil];
myChartClass.radius=100;
[self.view addSubview:myChartClass];

Regards.