Setting the color of UIAlertView in iPhone

In many cases, the requirement is to show an alert view with black appearance. In that case , we have to opt for a custom view that resembles with alert view.

But I have a solution , instead of creating custom view, we can create a subclass of UIAlertView and using CGCgraphics we can modify it and use it in our application.

.h file
@interface proAlertView : UIAlertView 

{

 

}

 -(void) setBackgroundColor:(UIColor *) background withStrokeColor:(UIColor *) stroke;

.m file
 
@interface proAlertView (Private)

 

 - (void) drawRoundedRect:(CGRect) rect inContext:(CGContextRef) 
context withRadius:(CGFloat) radius;

 

@end

 

static UIColor *fillColor = nil;

static UIColor *borderColor = nil;

 

 

@implementation proAlertView

 

 

- (void) setBackgroundColor:(UIColor *) background withStrokeColor:(UIColor *) stroke

{

if(fillColor != nil)

{

[fillColorrelease];

[borderColorrelease];

}

 

fillColor = ;

borderColor = [stroke retain];

}

 

- (id) initWithFrame:(CGRect)frame

{

    if((self = [super initWithFrame:frame]))

{

        if(fillColor == nil)

{

 

}

    }

 

    returnself;

}

 

- (void) layoutSubviews

{

for (UIView *sub in [self subviews])

{

if([sub class] == [UIImageView class] && sub.tag == 0)

{

[sub removeFromSuperview];

break;

}

}

}

 

- (void) drawRect:(CGRect)rect

{

CGContextRef context = UIGraphicsGetCurrentContext();

 

CGContextClearRect(context, rect);

CGContextSetAllowsAntialiasing(context, true);

CGContextSetLineWidth(context, 0.0);

CGContextSetAlpha(context, 0.8); 

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [borderColorCGColor]);

CGContextSetFillColorWithColor(context, [fillColorCGColor]);

 

CGFloat backOffset = 2;

CGRect backRect = CGRectMake(rect.origin.x + backOffset, 

rect.origin.y + backOffset, 

rect.size.width - backOffset*2, 

rect.size.height - backOffset*2);

 

[selfdrawRoundedRect:backRect inContext:context withRadius:8];

CGContextDrawPath(context, kCGPathFillStroke);

 

CGRect clipRect = CGRectMake(backRect.origin.x + backOffset-1, 

backRect.origin.y + backOffset-1, 

backRect.size.width - (backOffset-1)*2, 

backRect.size.height - (backOffset-1)*2);

 

[selfdrawRoundedRect:clipRect inContext:context withRadius:8];

CGContextClip (context);

 

CGGradientRef glossGradient;

CGColorSpaceRef rgbColorspace;

size_t num_locations = 2;

CGFloat locations[2] = { 0.0, 1.0 };

CGFloat components[8] = { 1.0, 1.0, 1.0, 0.35, 1.0, 1.0, 1.0, 0.06 };

rgbColorspace = CGColorSpaceCreateDeviceRGB();

glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, 

components, locations, num_locations);

 

CGRect ovalRect = CGRectMake(-130, -115, (rect.size.width*2), 

rect.size.width/2);

 

CGPoint start = CGPointMake(rect.origin.x, rect.origin.y);

CGPoint end = CGPointMake(rect.origin.x, rect.size.height/5);

 

CGContextSetAlpha(context, 1.0); 

CGContextAddEllipseInRect(context, ovalRect);

CGContextClip (context);

 

CGContextDrawLinearGradient(context, glossGradient, start, end, 0);

 

CGGradientRelease(glossGradient);

CGColorSpaceRelease(rgbColorspace); 

}

 

- (void) drawRoundedRect:(CGRect) rrect inContext:(CGContextRef) context 

  withRadius:(CGFloat) radius

{

CGContextBeginPath (context);

 

CGFloat minx = CGRectGetMinX(rrect), midx = CGRectGetMidX(rrect), 

maxx = CGRectGetMaxX(rrect);

 

CGFloat miny = CGRectGetMinY(rrect), midy = CGRectGetMidY(rrect), 

maxy = CGRectGetMaxY(rrect);

 

CGContextMoveToPoint(context, minx, midy);

CGContextAddArcToPoint(context, minx, miny, midx, miny, radius);

CGContextAddArcToPoint(context, maxx, miny, maxx, midy, radius);

CGContextAddArcToPoint(context, maxx, maxy, midx, maxy, radius);

CGContextAddArcToPoint(context, minx, maxy, minx, midy, radius);

CGContextClosePath(context);

}