IOS第16天(1,Quartz2D基本图像绘制）

***************基本图像绘制 画线

#import "HMLineView.h"

@implementation HMLineView

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

// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.

/**
 *  什么调用：当你视图第一次显示的时候就会调用
 *  作用：绘图
 *  @param rect = self.bounds
 */
- (void)drawRect:(CGRect)rect
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    UIBezierPath *path = [UIBezierPath bezierPath];

    CGPoint startP = CGPointMake(, );
    CGPoint endP = CGPointMake(, );
    CGPoint controlP = CGPointMake(, );
    [path moveToPoint:startP];
    [path addQuadCurveToPoint:endP controlPoint:controlP];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    // 4.渲染上下文到视图
    CGContextStrokePath(ctx);

}

- (void)draw2Line
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    UIBezierPath *path = [UIBezierPath bezierPath];

    // 设置起点
    [path moveToPoint:CGPointMake(, )];

    // 添加一条线到某个点
    [path addLineToPoint:CGPointMake(, )];

    //    // 设置起点
    //    [path moveToPoint:CGPointMake(10, 10)];
    //
    //    // 添加一条线到某个点
    //    [path addLineToPoint:CGPointMake(125, 100)];

    UIBezierPath *path1 = [UIBezierPath bezierPath];

    [path1 moveToPoint:CGPointMake(, )];

    [path1 addLineToPoint:CGPointMake(, )];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);
    CGContextAddPath(ctx, path1.CGPath);

    // 设置绘图状态
    // 设置线宽
    CGContextSetLineWidth(ctx, );
    CGContextSetLineCap(ctx, kCGLineCapRound);
    //    CGContextSetRGBStrokeColor(ctx, 1, 0, 0, 1);
    [[UIColor redColor] set];

    // 4.渲染上下文到视图
    CGContextStrokePath(ctx);
}

- (void)drawLine
{
    // 1.获取上下文
    // CGContextRef CG CoreGraphics Ref 引用
    // 目前学的上下文都跟UIGraphics有关，以后想直接获取上下文，直接敲一个UIGraphics
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.设置绘图信息(拼接路径)
    UIBezierPath *path = [UIBezierPath bezierPath];

    // 设置起点
    [path moveToPoint:CGPointMake(, )];

    // 添加一条线到某个点
    [path addLineToPoint:CGPointMake(, )];
    [path addLineToPoint:CGPointMake(, )];
    // 3.把路径添加到上下文
    // 直接把UIKit的路径转换成CoreGraphics，CG开头就能转
    CGContextAddPath(ctx, path.CGPath);

    // 4.把上下文渲染到视图
    // Stroke描边
    CGContextStrokePath(ctx);
}

@end

******基本的图形的绘制

#import "HMShapeView.h"

@interface HMShapeView()

@property (nonatomic, weak) UILabel *label;

@end

@implementation HMShapeView

- (UILabel *)label
{
    if (_label == nil) {
        UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(, , , )];
        label.text = @"s";
        label.font = [UIFont systemFontOfSize:];
        label.textColor = [UIColor yellowColor];
        label.textAlignment = NSTextAlignmentCenter;
        [self addSubview:label];
        _label = label;
    }
    return _label;
}

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

- (void)awakeFromNib
{
//    self.label;
}

// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.

// 扇形行
- (void)drawRect:(CGRect)rect
{
    // Drawing code

    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    CGPoint center = CGPointMake(, );
    CGFloat radius = ;
    CGFloat startA = ;
    CGFloat endA = M_PI_2;
    UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];

    [path addLineToPoint:center];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    // 4.渲染上下文
//    CGContextStrokePath(ctx);
    CGContextFillPath(ctx);

}

- (void)drawArc
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    CGPoint center = CGPointMake(, );
    CGFloat radius = ;
    CGFloat startA = ;
    CGFloat endA = M_PI_2;
    UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    // 4.渲染上下文
    CGContextStrokePath(ctx);
}

// 圆行
- (void)drawCircle
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(, , , )];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    // 4.渲染上下文
    CGContextStrokePath(ctx);

}
//  矩形
- (void)drawRectangle
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    UIBezierPath *path = [UIBezierPath bezierPathWithRect:CGRectMake(, , , )];
    path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(, , , ) cornerRadius:];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    // 4.渲染上下文
    CGContextStrokePath(ctx);
}

//三角
- (void)drawSupernene
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    // 2.拼接路径
    UIBezierPath *path = [UIBezierPath bezierPath];

    CGPoint startP = CGPointMake(, );

    [path moveToPoint:startP];

    [path addLineToPoint:CGPointMake(, )];

    [path addLineToPoint:CGPointMake(, )];

    // 从路径的终点连接到起点
    [path closePath];
    //    [path addLineToPoint:startP];

    // 3.把路径添加到上下文
    CGContextAddPath(ctx, path.CGPath);

    [[UIColor blueColor] setFill];
    [[UIColor redColor] setStroke];

    CGContextSetLineWidth(ctx, );

    // 4.渲染上下文
    //    CGContextStrokePath(ctx);
    //    CGContextFillPath(ctx);
    // 即填充又描边 kCGPathFillStroke
    CGContextDrawPath(ctx, kCGPathFillStroke);
}

@end