Animated Line Dash Pattern 2

C4WorkSpace.m

//
//  C4WorkSpace.m
//  Examples
//
//  Created by Travis Kirton
//

#import "C4WorkSpace.h"

@interface C4WorkSpace ()
-(void)animate;
@end

@implementation C4WorkSpace {
    C4Shape *circle;
    CGFloat patternWidth;
}

-(void)setup {
    //create the circle and center it
    circle = [C4Shape ellipse:CGRectMake(0, 0, 200, 200)];
    circle.center = self.canvas.center;
    
    //create a dash pattern
    //this pattern is [1,2,3,..,628];
    CGFloat dashPattern[628];
    int i;
    for(i = 0; i < 628; i++) {
        dashPattern[i] = i+1;
        patternWidth += i;
    }
    
    //thicken the line and set its dash pattern
    circle.lineWidth = 30.0f;
    circle.fillColor = [UIColor clearColor];
    [circle setDashPattern:dashPattern pointCount:1260];

    //add the line to the canvas
    [self.canvas addShape:circle];

    //animate it after a short delay
    [self runMethod:@"animate" afterDelay:0.1f];
}

-(void)animate {
    //duration = 5 minutes (60s * 3 = 180);
    circle.animationDuration = 180.0f;
    circle.animationOptions = AUTOREVERSE;
    circle.strokeColor = C4BLUE;
    
    //set the final dash phase to the entire width of the pattern
    circle.lineDashPhase = patternWidth;
}

@end