斯乌i的博客public class jisuanqi { public static void main(String[] args){ //建立新窗体对象 Frame f = new Frame("计算器"); //f.setLayout(new BorderLayout(500,200));//书上没有这句 Panel p1 = new Panel(); ...
QL-L的博客 Unable to start activity ComponentInfo{com.example.xmljavalayout/com.example.xmljavalayout.MainActivity}: java.lang.ClassCastException: androidx.gridlayout.widget.GridLayout cannot be cast to android...