ios - 无法缩放形状以匹配 UIView 的尺寸

Question

我创建了一个自定义 View ，可以绘制不同边的形状。该 View 作为 subview 添加到主视图，如下所示。形状具有不同的尺寸。

下面是我的源码

-(instancetype) initWithSides:(NSUInteger) sides andFrame:(CGRect)frame {
        self = [super initWithFrame:frame];
        if (self) {
            [self setBackgroundColor:[UIColor clearColor]];
            self.sides = sides;
            self.radius =  CGRectGetWidth(self.frame) * 1.5 / sides);
        }
        return self;
}

    -(void) drawRect:(CGRect) frame {
// Sides is passed as constructor argument. 4 sides means a quadrilateral etc.
// Get CGPAthRef instance

        CGFloat angle = DEGREES_TO_RADIANS(360 / ((CGFloat) self.sides));
    int count = 0;
    CGFloat xCoord = CGRectGetMidX(self.frame);
    CGFloat yCoord = CGRectGetMidY(self.frame);
    while (count < self.sides) {
        CGFloat xPosition =
            xCoord + self.radius * cos(angle * ((CGFloat) count));
        CGFloat yPosition =
            yCoord + self.radius * sin(angle * ((CGFloat) count));

        [self.points addObject:[NSValue valueWithCGPoint:CGPointMake(xPosition, yPosition)]];

        count ++;
    }

    NSValue* v = [self.points firstObject];
    CGPoint first = v.CGPointValue;

    CGMutablePathRef path = CGPathCreateMutable();
     CGPathMoveToPoint(path, nil, first.x, first.y);

    for (int ix = 1; ix < [self.points count]; ix++) {
        NSValue* pValue = [self.points objectAtIndex:ix];
        CGPoint p = pValue.CGPointValue;
        CGPathAddLineToPoint(path, nil, p.x, p.y);
    }

    CGPathCloseSubpath(path);


   CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextAddPath(context, path);
    [self colourView:context withPath:path];
  }

-(void) colourView:(CGContextRef) context withPath:(CGPathRef) ref {
    NSUInteger num = arc4random_uniform(8) + 1;
    UIColor* color = nil;
    switch (num) {
        case 1:
            color = [UIColor redColor];
            break;
        case 2:
            color = [UIColor greenColor];
            break;
        case 3:
            color = [UIColor yellowColor];
            break;
        case 4:
            color = [UIColor blueColor];
            break;
        case 5:
            color = [UIColor orangeColor];
            break;
        case 6:
            color = [UIColor brownColor];
            break;
        case 7:
            color = [UIColor purpleColor];
            break;
        case 8:
            color = [UIColor blackColor];
            break;
        default:
            break;
    }

    CGContextSetFillColorWithColor(context, color.CGColor);
    CGContextFillPath(context);
}

这构成了一个单一的形状。这就是我绘制其余 View 的方式。

-(void) initDrawView {
    NSUInteger width = CGRectGetWidth(self.view.bounds) / 8;
    NSUInteger height = (CGRectGetHeight(self.view.frame))/ 8;
    UITapGestureRecognizer *singleFingerTap =
        [[UITapGestureRecognizer alloc] initWithTarget:self
                                            action:@selector(handleSingleTap:)];
    for (int i = 0 ; i < 8; i++) {
        CGFloat yCoord = i * height + i * 15;
        for (int j = 0; j < 8; j ++) {
            int side = 3 + arc4random() % 8;
            CGFloat xCoord = j * width;

            SimpleRegularPolygonView* view =
                [[SimpleRegularPolygonView alloc] initWithSides:side andFrame:CGRectMake(xCoord, yCoord, width, height)];
            [view sizeToFit];
            view.viewEffectsDelegate = self;
            [view setTag: (8 * i + j)];
            [self.view addGestureRecognizer:singleFingerTap];
            [self.view addSubview:view];
        }
    }
}

1) 我不知道如何使它们具有相同的尺寸。我怎样才能做到这一点？ (第一张图)

2) 图片未按比例放大到 UIView 的大小(第二张图片)。

Answer 1

您当前的代码使半径与边数成反比:

self.radius =  CGRectGetWidth(self.frame) * 1.5 / sides;

所以边越多，图像越小。一个快速的解决方法是将半径设为框架宽度的一半:

self.radius =  CGRectGetWidth(self.frame) /2;

这意味着边数为偶数的形状会填满框架宽度。但是边数为奇数的那些看起来左边有空间。如果要对此进行调整，则需要对宽度进行更详细的计算，并且还需要移动形状的“中心”。对于奇数边，半径需要为:

self.radius =  CGRectGetWidth(self.frame) /(1 + cos(angle / 2));

xCoord 需要:

CGFloat xCoord = CGRectGetMinX(self.frame) + self.radius * cos(angle/2);