title: flutter: how to suit all the screen sizes with the same program?
body: <p>I'm new in flutter. UI designers provide an XD based on the iPad. When I deal with the size of the widgets, I just set the size the same as the XD shows (in px). For example: <code>height: 100, width: 100</code>. But today I tested the app on a physical device(a mobile phone much smaller than an iPad), everything is overflow. I ignore this problem all the time when I use an emulator the same size as the iPad in XD. So how to adapt to different devices with different screen sizes? Is there a function or some other tools helpful?</p>