AnyObject 到 CGPoint

AnyObject To CGPoint

我似乎无法弄清楚,我有一个 Objective-C 函数 returns 一个 NSArray,我确信 NSArray 中的数据包含 CGPoint 对象 我到底该如何投射这是一个数组

这是函数

+(NSArray *)translatePoints:(NSArray *)points fromView:(UIView *)fromView toView:(UIView *)toView
{
    NSMutableArray *translatedPoints = [NSMutableArray new];

    // The points are provided in a dictionary with keys X and Y
    for (NSDictionary *point in points) {
        // Let's turn them into CGPoints
        CGPoint pointValue = CGPointMake([point[@"X"] floatValue], [point[@"Y"] floatValue]);
        // Now translate from one view to the other
        CGPoint translatedPoint = [fromView convertPoint:pointValue toView:toView];
        // Box them up and add to the array
        [translatedPoints addObject:[NSValue valueWithCGPoint:translatedPoint]];
    }

    return [translatedPoints copy];
}

您的 translatesPoints 方法 returns 一个 NSArray 包含 NSValue 包裹 CGPoint 的方法。让我们创建这样一个数组:

let arr:NSArray = [NSValue(CGPoint: CGPointMake(1,2)), NSValue(CGPoint: CGPointMake(3,4))]

您可以从此数组中获取值并对它们调用 CGPointValue()

for val in arr as [NSValue] {
    let point = val.CGPointValue()
    println("CGPoint = (\(point.x), \(point.y))")
}

如果需要,您可以将整个 NSArray 转换为 Swift 个 CGPoint 数组,如下所示:

let points = (arr as [NSValue]).map({[=12=].CGPointValue()})

现在 points 的类型为 [CGPoint]