Question

我试图在可可中绘制一条bezier曲线，并且我得到的EXC_BAD_INSTRUCTION似乎没有任何意义。

这是我的代码：

NSBezierPath *path = [NSBezierPath bezierPath];
[path setLineWidth: 1.0f];

NSPoint a = NSMakePoint(0, 0);
NSPoint c1 = NSMakePoint(0, 50);
NSPoint c2 = NSMakePoint(50, 100);
NSPoint b = NSMakePoint(100, 100);

[path moveToPoint:a];
[path addCurveToPoint: b controlPoint1:c1 controlPoint2:c2];

[[NSColor colorWithDeviceRed:1 green:0 blue:0 alpha:1] set];

[path stroke];

执行以下行时，我的应用程序崩溃：

[path addCurveToPoint: b controlPoin1:c1 controlPoint2:c2];

Xcode告诉我它在我的主循环中崩溃了：

[NSApp runModalSession:modalSession];

错误输出如下：

2016-12-08 04:38:35.344601 unit_tests[10606:777278] -[NSBezierPath addCurveToPoint:controlPoint1:controlPoint2:]: unrecognized selector sent to instance 0x100428fa0

（lldb）

Answer 1

您有controlPoin1: c1的拼写错误应该是controlPoint1: c1

实际上我刚刚意识到你的目标是AppKit（NSBezierPath）而不是UIKit（UIBezierPath）。

编辑：

对于AppKit使用：-[NSBezierPath curveToPoint: controlPoint1: controlPoint2:]

对于UIKit使用-[UIBezierPath addCurveToPoint: controlPoint1: controlPoint2:]

addCurveToPoint与EXC_BAD_INSTRUCTION崩溃

1 个答案: