Flutter中CupertinoNavigationBar控件背景透明化

在flutter中使用CupertinoNavigationBar让其背景完全透明化。只需要实现颜色类将其alpha改为0xFF即可.

class AlphaColor extends Color {  
  const AlphaColor() : super(0x00000000);  
  @override  
  int get alpha => 0xFF;  
}

使用

CupertinoNavigationBar(  
  border: Border.all(width: 0, color: Colors.transparent),  
  backgroundColor: const AlphaColor(),  
  automaticBackgroundVisibility: false,  
  enableBackgroundFilterBlur: false,  
  transitionBetweenRoutes: false,  
),