//
//  IGraph.m
//  Tutorial_Quartz_Circle
//
//  Created by JON MOODY on 9/8/11.
//  Copyright 2011 __MyCompanyName__. All rights reserved.
//

#import "IGraph.h"

@implementation IGraph

- (id)init
{
    self = [super init];
    if (self) {
        // Initialization code here.
    }
    
    return self;
}
- (id)initWithFrame:(CGRect)frame {
    if ((self = [super initWithFrame:frame])) {
        // Initialization code
    }
    backgroundImage = [UIImage imageNamed:@"apple.jpg"];
    m_circle=false;
    return self;
}

- (void)drawRect:(CGRect)rect {
	CGContextRef	context = UIGraphicsGetCurrentContext();	
	CGPoint drawingTargetPoint = CGPointMake(0,0);
	[backgroundImage drawAtPoint:drawingTargetPoint];	
    
 	
    if(m_circle){
      
        CGGradientRef gradient;
        CGColorSpaceRef colorSpace;
        CGFloat locations[] = {0.0,1.0};
        CGFloat components[] = { 0.5,1.0,1.0,1.0, 0.25,0.5,0.5,1.0 };
        colorSpace = CGColorSpaceCreateDeviceRGB();
       // colorSpace = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
        gradient = CGGradientCreateWithColorComponents(colorSpace,components,locations,
                                                       sizeof(locations)/sizeof(CGFloat));
        CGPoint start = {70.0,130.0}, end = {100.0,100.0};
        CGFloat startRadius = 0.0, endRadius = 90.0;
        CGContextDrawRadialGradient(context,gradient,start,startRadius,end,endRadius,0);
        CGGradientRelease(gradient);
        CGColorSpaceRelease(colorSpace);
    }
}
- (void)circle{

    m_circle=true;
    [self setNeedsDisplay];
}
@end

#import <Foundation/Foundation.h>

@interface IGraph : UIView {
    
	UIImage* backgroundImage;
    Boolean m_circle;
}
-(void)circle;

@end

sample code:
Tutorial_Quartz_Circle

By admin-powenko

Dr. Powen Ko is a teacher and CEO on LoopTek LLC, and like to teaching. if you need to class, please let PowenKo know, he will love to service and sharing. LoopTek web site is www.looptek.com

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