[windows/flutter] Grid排版

1.

List<Container> _buildGridTileList(int count) => List.generate(
    count,
    (i) => Container(
    child: Image.asset('images/pic$i.jpg')
    )
);

Widget _buildGrid() => GridView.extent(
    maxCrossAxisExtent: 150.0,
    padding: const EdgeInsets.all(4.0),
    mainAxisSpacing: 4.0,
    crossAxisSpacing: 4.0,
    children: _buildGridTileList(30)
);

return
        _buildGrid();

pubspec.yaml

  assets:
   [images/]

1-1. padding是最外圍的內距
1-2. mainAxisSpacing是上下間距
1-3. crossAxisSpacing是左右間距
1-4. maxCrossAxisExtent是75時，有4欄6列多；50時，有6欄5列(其實就是一個項目寬度75像素或50像素)