const Tooltip({
super.key,
this.message,
this.richMessage,
this.height,
this.padding,
this.margin,
this.verticalOffset,
this.preferBelow,
this.excludeFromSemantics,
this.decoration,
this.textStyle,
this.textAlign,
this.waitDuration,
this.showDuration,
this.triggerMode,
this.enableFeedback,
this.onTriggered,
this.child,
})
注意：是在所child控件上长按才显示message
Tooltip( message: '点击进行用户名和密码认证，完成系统登录', child: ElevatedButton( onPressed: () { _login(); }, child: const Text('Login'), ), ),