java - 我如何更改它以使用我的电视类(class)？

Question

Create a Television store that can hold three Television objects in an array. Use the Television class below:

   class Television
   {
       boolean isOn;
   } // end class Television

Use a for loop to print the isOn instance variable for each Television in the TelevisionStore. Use a second for loop to change the isOn instance variable for each Television to “true”. Finally, use a third for loop to print the isOn instance variable for each Television in the TelevisionStore array.

所以我创建了一个具有正确输出的程序:

public class TelevisionDriver
    {
    public static void main( String[] args )
        {
         boolean isOn[] = new boolean[3];
         isOn[0] = false;
         isOn[1] = false;
         isOn[2] = false;

         System.out.println( "Opening the tv store for the day... tv status:" + 
         "\n" );

         for( int x = 0; x < 3; x++ )
            {
            System.out.println( "Television" + x + " on? " + isOn[x] );
            }

         System.out.println( "\n" + "Turning the tv's on..." + "\n" );

          for( int y = 0; y < 3; y++ )
            {
            isOn[0] = true;
            isOn[1] = true;
            isOn[2] = true;

            System.out.println( "Television" + y + " on? " + isOn[y] );
            }
        }
    }

这被认为是正确的吗？我意识到该程序无法访问电视类，并且不知道如何更改它。

Answer 1

您需要构造电视对象:

Television tvs[] = new Television[3];
for (int i = 0; i < 3; i++) {
    tvs[i] = new Television();
    tvs[i].isOn = false;
}

然后访问它们是否打开就变成这样:

for (int x = 0; x < 3; x++) {
    System.out.println("Television" + x + " on? " + tvs[x].isOn);
}

确实应该封装 isOn 变量，并且 Television 类应该有一个构造函数，但我不确定您是否已经学会了。