Here, the new value (a string representing a whitespace-delimited list of numbers) entered by the user will be copied into the object's instance variable.
Here, the new value (a string representing a whitespace-delimited list of numbers) entered by the user will be copied into the object's instance variable.
在界面上，一旦新的值被输入，对象中的属性也随之改变(用空格分割的数字列表字符串)。