title: How can I call setState of a child widget from a parent widget?
body: <p>Whenever the user clicks on the back button of the device, I need to change a variable value inside the child widget and call <code>setState()</code>. The thing is that when I click the back button, the onWillPopScope() of the parent widget is called and not of the child widget. So, I need from the parent to change the variable value of the child widget state and call <code>setstate()</code> inside the child widget. Or if there is a way to do that the onWillPopScope of the child widget will be called, it would also solve my problem. Is there anything I can do?</p>