¿Cómo configuro el color de fondo en UIView usando CGContext?

Question

he desarrollado la aplicación en la que quiero establecer el color de fondo de UIView que ya está establecido en el código de UIViewController.The está por debajo,

@implementation frmGraphView 


- (id)initWithFrame:(CGRect)frame { 
    if (self = [super initWithFrame:frame]) 
    { 
     // Initialization code 
    } 
    return self; 
} 


- (void)drawRect:(CGRect)rect 
{ 
    CGContextRef ctx = UIGraphicsGetCurrentContext(); 
    CGContextClearRect(ctx, rect); 
    //CGContextSetCMYKFillColor(ctx, 35.0, 56.0, 34.0, 30.0, 1.0); 
    //CGContextSetRGBFillColor(ctx, 92.0f, 95.0f, 97.0f, 1.0f); 
    //CGContextFillRect(ctx, CGRectMake(0, 0, 300, 280)); 



    CGContextSetRGBStrokeColor(ctx, 2.0, 2.0, 2.0, 1.0); 
    CGContextSetLineWidth(ctx, 2.0); 
    float fltX1,fltX2,fltY1,fltY2=0; 
    NSArray *hoursInDays = [[NSArray alloc] initWithObjects:@"0",@"1" ,@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9",@"10",@"11",@"12", nil]; 
    fltX1 = 30; 
    fltY1 = 5; 
    fltX2 = fltX1; 
    fltY2 = 270; 

    //Dividing the Y-axis 
    CGContextMoveToPoint(ctx, fltX1, fltY1); 
    CGContextAddLineToPoint(ctx, fltX2, fltY2); 
    //float y = 275; 
    for(int intIndex = 0 ; intIndex < [hoursInDays count] ; fltY2-=20, intIndex++) 
    { 
     CGContextSetRGBStrokeColor(ctx, 2.0, 2.0, 2.0, 1.0); 
     CGContextMoveToPoint(ctx, fltX1-3 , fltY2); 
     CGContextAddLineToPoint(ctx, fltX1+3, fltY2); 
     CGContextSelectFont(ctx, "Helvetica", 14.0, kCGEncodingMacRoman); 
     CGContextSetTextDrawingMode(ctx, kCGTextFill); 
     CGContextSetRGBFillColor(ctx, 0, 255, 255, 1); 
     CGAffineTransform xform = CGAffineTransformMake(
                 1.0, 0.0, 
                 0.0, -1.0, 
                 0.0, 0.0); 
     CGContextSetTextMatrix(ctx, xform); 
     const char *arrayDataForYAxis = [[hoursInDays objectAtIndex:intIndex] UTF8String]; 
     CGContextShowTextAtPoint(ctx, fltX1-18, fltY2-18 , arrayDataForYAxis, strlen(arrayDataForYAxis)); 
     CGContextStrokePath(ctx); 
    } 
    CGContextSetRGBStrokeColor(ctx, 2.0, 2.0, 2.0, 1.0); 
    CGContextSetLineWidth(ctx, 2.0); 

    fltX1 = 5; 
    fltY1 = 250; 
    fltX2 = 270; 
    fltY2 = fltY1; 

    NSArray *weekDays =[[NSArray alloc] initWithObjects:@"Sun", @"Mon", @"Tus", @"Wed", @"Thu", @"Fri", @"Sat", nil]; 
    //Dividing the X-axis 
    CGContextMoveToPoint(ctx, fltX1, fltY1); 
    CGContextAddLineToPoint(ctx, fltX2, fltY2); 
    //float y = 275; 
    for(int intIndex = 0 ; intIndex < [weekDays count] ; fltX1+=33, intIndex++) 
    { 
     CGContextSetRGBStrokeColor(ctx, 2.0, 2.0, 2.0, 1.0); 
     CGContextMoveToPoint(ctx, fltX1+52 , fltY2-3); 
     CGContextAddLineToPoint(ctx, fltX1+52, fltY2+3); 
     CGContextSelectFont(ctx, "Arial", 15.0, kCGEncodingMacRoman); 
     CGContextSetTextDrawingMode(ctx, kCGTextFill); 
     CGContextSetRGBFillColor(ctx, 0, 255, 255, 1); 
     CGAffineTransform xform = CGAffineTransformMake(
                 1.0, 0.0, 
                 0.0, -1.0, 
                 0.0, 0.0); 
     CGContextSetTextMatrix(ctx, xform); 
     const char *arrayDataForXAxis = [[weekDays objectAtIndex:intIndex] UTF8String]; 
     CGContextShowTextAtPoint(ctx, fltX1+37, fltY2+18 , arrayDataForXAxis, strlen(arrayDataForXAxis)); 
     CGContextStrokePath(ctx); 

     } 
} 

@end 

Answer 1

¿Qué hay de este código?

- (void)drawRect:(CGRect)rect { 

    [super drawRect:rect]; 
    CGContextRef context = UIGraphicsGetCurrentContext(); 

    CGRect drawRect = CGRectMake(rect.origin.x, rect.origin.y,rect.size.width, rect.size.height); 

    CGContextSetRGBFillColor(context, 100.0f/255.0f, 100.0f/255.0f, 100.0f/255.0f, 1.0f); 
    CGContextFillRect(context, drawRect); 
} 

Answer 2

Swift 3

UIGraphicsBeginImageContextWithOptions(size, true, UIScreen.main.scale) 
let context = UIGraphicsGetCurrentContext() 
context?.setFillColor(UIColor.green.cgColor) 
let image = UIGraphicsGetImageFromCurrentImageContext() 
UIGraphicsEndImageContext() 
return image