IOS quartz2d generating pictures from Uicolor

Normal Build

Example code:

Here the way to achieve the normal generation of pictures-(void) DrawRect: (cgrect) rect {    CGRect cxrect = CGRectMake (0, 0,.);        Uigraphicsbeginimagecontextwithoptions (cxrect.size, NO, 0);        [[Uicolor Redcolor] setfill];        Uirectfill (cxrect);        UIImage * image = Uigraphicsgetimagefromcurrentimagecontext ();        Uigraphicsendimagecontext ();        Uiimageview * ImageView = [[Uiimageview alloc]initwithframe:cgrectmake (+, +, +)];        Imageview.image = image;        [Self addsubview:imageview];}

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Gradient Color generation

Example code:

Here is the way to implement the gradient color generation picture-(void) DrawRect: (cgrect) rect {cgrect cxrect = CGRectMake (0, 0, 1, 1);    Uigraphicsbeginimagecontextwithoptions (cxrect.size, NO, 0);    Cgcontextref context = Uigraphicsgetcurrentcontext ();    Uicolor * Begincolor = [Uicolor Greencolor];    Uicolor * EndColor = [Uicolor Redcolor];    Drawlineargradient (context, Cxrect, Begincolor.cgcolor, Endcolor.cgcolor);        Cgcontextrestoregstate (context);    UIImage *image = Uigraphicsgetimagefromcurrentimagecontext ();    Uigraphicsendimagecontext ();        Uiimageview * ImageView = [[Uiimageview alloc]initwithframe:cgrectmake (20, 20, 100, 100)];        Imageview.image = image; [Self addsubview:imageview];}  void Drawlineargradient (Cgcontextref context, CGRect rect, Cgcolorref startcolor, Cgcolorref endcolor) {Cgcolorspaceref    ColorSpace = Cgcolorspacecreatedevicergb ();        CGFloat locations[] = {0.0, 1.0};        Nsarray *colors = @[(__bridge ID) startcolor, (__bridge ID) EndColor]; Cggradientref gradient = CGGRadientcreatewithcolors (ColorSpace, (__bridge cfarrayref) colors, locations);    Cgpoint startPoint = cgpointmake (RECT.SIZE.WIDTH/2, 0);        Cgpoint endPoint = Cgpointmake (RECT.SIZE.WIDTH/2, rect.size.height/1.5);    Cgcontextsavegstate (context);    Cgcontextaddrect (context, rect);    Cgcontextclip (context);    Cgcontextdrawlineargradient (context, gradient, startPoint, endPoint, 0); Cgcontextsetstrokecolorwithcolor (context, [[Uicolor Clearcolor] cgcolor]);}

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IOS quartz2d generating pictures from Uicolor