Objective-C绑定指针数组到c#

本文关键字：数组 指针 绑定 Objective-C | 更新日期: 2023-09-27 18:10:14

我正在尝试在Xamarin中绑定Objective-C库和c#。我试图绑定的类头是这样的:

@interface MGLPolyline : MGLMultiPoint <MGLOverlay>
+ (instancetype)polylineWithCoordinates:(CLLocationCoordinate2D *)coords
                              count:(NSUInteger)count;

我不明白的是函数的第一个参数是什么。我试着让绑定如下:

Static][Export("polylineWithCoordinates:count:")]
    [Internal]
    MGLPolyLine PolyLineWithCoordinates(IntPtr coord, int count);

public partial class MGLPolyLine
{
    public static unsafe MGLPolyLine PolyLineWithCoordinates(CLLocationCoordinate2D[] coords) 
    {
        unsafe
        {
            GCHandle handle = GCHandle.Alloc(coords);
            IntPtr pointer = (IntPtr)handle;
            MGLPolyLine line = MGLPolyLine.PolyLineWithCoordinates(pointer,2);
            handle.Free();
            return line;
        }
    }
}

以上代码总是从MGLPolyLine返回null。PolyLineWithCoordinates(指针，2)调用，这使我相信我没有正确传递数组。做这个绑定的正确方法是什么?

感谢

编辑

我用Objective-Sharpie来看看它会为我创建什么绑定，这是我得到的:

// +(instancetype)polygonWithCoordinates:(CLLocationCoordinate2D *)coords count:(NSUInteger)count;
[Static]
[Export ("polygonWithCoordinates:count:")]
unsafe MGLPolygon PolygonWithCoordinates (CLLocationCoordinate2D* coords, nuint count);

现在的问题是我得到错误"btouch: Unknown kind CoreLocationCoordinate2D* coordinates in method 'MGLPolygon。PolygonWithCoordinates"(B1002)

Objective-C绑定指针数组到c#

原来我使用GCHandle不正确。可行的解决方案是:

   //ApiDefinition.cs
    [Static][Export ("polylineWithCoordinates:count:")][Internal]
 MGLPolyline PolylineWithCoordinates (IntPtr coords, nuint count);
// Extra.cs
public partial class MGLPolyline
{
    public static unsafe MGLPolyline PolylineWithCoordinates(CLLocationCoordinate2D[] coords)
    {
        MGLPolyline line = null;
        fixed(void* arrPtr = coords)
        {
            IntPtr ptr = new IntPtr(arrPtr);
            line = MGLPolyline.PolylineWithCoordinates(ptr, 2);   
        }
        return line;
    }
}
相关文章：