用于使用键从AssetBundle获取图像.
new Image.network, 用于从URL获取图像.
new Image.file,用于从文件获取图像.
new Image.memory,用于从Uint8List...Image.memory(Uint8List bytes, { Key key, double scale: 1.0, double width, double height, Color color,...ImageRepeat.noRepeat, Rect centerSlice, bool matchTextDirection: false, bool gaplessPlayback: false })
创建一个显示从Uint8List