iphone 自定义控件

iPhone中自绘实现步骤 1. 继承@interface MyView : UIView { 2. 实现- (void)drawRect:(CGRect)rect 3. 调用addSubView把新生成的view加入进来显示 addSubView[window addSubview:viewController.view]; 4.示例代码 - (void)drawRect:(CGRect)rect {     // create the bitmap context     CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();     CGContextRef context = CGBitmapContextCreate(nil,100,100,8,400, colorSpace,kCGImageAlphaPremultipliedLast);     CFRelease(colorSpace);          //    create an arrow image     // set the fill color     CGColorRef fillColor = [[UIColor blackColor] CGColor];     CGContextSetFillColor(context, CGColorGetComponents(fillColor));          CGContextBeginPath(context);     CGContextMoveToPoint(context, 8.0f, 13.0f);     CGContextAddLineToPoint(context, 24.0f, 4.0f);     CGContextAddLineToPoint(context, 24.0f, 22.0f);     CGContextClosePath(context);     CGContextFillPath(context);     CGContextSelectFont ( context, "Arial", 10.f, kCGEncodingMacRoman );     CGContextSetRGBFillColor ( context, 0.0f, 0.0f, 0.f, 1.f );     CGContextSetShouldAntialias ( context, 0 );         CGContextShowText(context, "hh", 2);               // convert the context into a CGImageRef     CGImageRef image = CGBitmapContextCreateImage(context);     CGContextRelease(context);          UIImage* image2 = [UIImage imageWithCGImage:image];     [image2 drawInRect:CGRectMake(0, 0, 120, 160)];          NSString* myStr = @"中文";     UIFont* font = [UIFont systemFontOfSize:12.0];     [myStr drawInRect: CGRectMake(160, 240, 100, 130) withFont:font lineBreakMode:UILineBreakModeWordWrap alignment:UITextAlignmentCenter];      }