flutter - 如何在flutter中的DecorationImage()内编写if语句

Question

同时在flutter项目中实现图像选择器。
1)当屏幕首次加载存储 Assets 图像时应显示
2)在图像选择器中单击图像后，该图像应替换 Assets 图像

                Align(
                alignment: Alignment.topCenter,
                 child:Container(
                 width: SizeConfig.safeBlockHorizontal*25,
                 height: SizeConfig.safeBlockHorizontal*25,
                 margin: EdgeInsets.only(top: SizeConfig.blockSizeHorizontal*20),
                 decoration: BoxDecoration(
                  shape: BoxShape.circle,
                  image: DecorationImage(
                    image: if(_image == null)     //before picking image load stored image
                    {
                      image:AssetImage('assets/images/avatar.jpg')
                    }
                    else{
                        Image.file(_image),     //after clicking image picker load clicked image
                    }
                    fit: BoxFit.fill),
                ),
               ),
              ),

Answer 1

您可以使用三元运算符，例如:

DecorationImage(
  image: _image == null ? AssetImage('assets/images/avatar.jpg') : Image.file(_image),
)