放在ButtonGroup中会有一个被选中的。如果非要使用ButtonGroup,请重写下面的方法: public void setSelected(ButtonModel m, boolean b) { if (b && m != null && m != selection) { ButtonModel oldSelection = selection; selection = m; if (oldSelection != null) { oldSelection.setSelected(false); } m.setSelected(true); } }
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(btn.isSelected()) btn.setSelected(false);
else btn.setSelected(true);
}
});
public void setSelected(ButtonModel m, boolean b) {
if (b && m != null && m != selection) {
ButtonModel oldSelection = selection;
selection = m;
if (oldSelection != null) {
oldSelection.setSelected(false);
}
m.setSelected(true);
}
}