当我想在Kotlin中为TextView的textColor设置动画时：
val animator = ObjectAnimator.ofInt(myTextView,"textColor",0xFF8363FF,0xFFC953BE)
发生此错误：
Error:(124,43) None of the following functions can be called with the arguments supplied: public open fun <T : Any!> ofInt(target: TextView!,xProperty: Property<TextView!,Int!>!,yProperty: Property<TextView!,path: Path!): ObjectAnimator! defined in android.animation.ObjectAnimator public open fun <T : Any!> ofInt(target: TextView!,property: Property<TextView!,vararg values: Int): ObjectAnimator! defined in android.animation.ObjectAnimator public open fun ofInt(target: Any!,propertyName: String!,xPropertyName: String!,yPropertyName: String!,path: Path!): ObjectAnimator! defined in android.animation.ObjectAnimator public open fun ofInt(vararg values: Int): ValueAnimator! defined in android.animation.ObjectAnimator
似乎在Kotlin中不能将值0xFF8363FF和0xFFC953BE强制转换为Int,但是,它在Java中是正常的：
ObjectAnimator animator = ObjectAnimator.ofInt(myTextView,0xFFC953BE);
有任何想法吗？提前致谢.
解决方法
0xFF8363FF(以及0xFFC953BE)是Long,而不是Int.
你必须明确地将它们转换为Int：
val animator = ObjectAnimator.ofInt(myTextView,0xFF8363FF.toInt(),0xFFC953BE.toInt())
关键是0xFFC953BE的数值是4291384254,因此它应该存储在Long变量中.但这里的高位是符号位,表示负数：-3583042,可以存储在Int中.
这就是两种语言之间的区别.在Kotlin中你应该添加 – 符号来表示负的Int,这在Java中是不正确的：
// Kotlin print(-0x80000000) // >>> -2147483648 (fits into Int) print(0x80000000) // >>> 2147483648 (does NOT fit into Int) // Java System.out.print(-0x80000000); // >>> -2147483648 (fits into Integer) System.out.print(0x80000000); // >>> -2147483648 (fits into Integer)