小编Rav*_*til的帖子

RenderFlex 底部溢出了 676 像素。在 SingleChildScrollView 中

Widget dashboard(context){\n    return AnimatedPositioned(\n      duration: duration,\n      top:0,\n      bottom:0,\n      left:isCollapsed ? 0 : 0.6 * screenWidth,\n      right:isCollapsed ? 0 : -0.2 * screenWidth,\n      child: ScaleTransition(\n        scale: _scaleAnimation,\n        child: Material(\n          animationDuration: duration ,\n          borderRadius: BorderRadius.all(\n            Radius.circular(40),\n          ),\n          elevation: 8,\n          color:backgroundColor,\n          child: Column(\n              crossAxisAlignment: CrossAxisAlignment.start,\n              children: <Widget>[\n              Container(\n                padding: const EdgeInsets.only(left: 16, right: 16, top: 48),\n                child: Row(\n                    mainAxisAlignment: MainAxisAlignment.spaceBetween,\n                    mainAxisSize: MainAxisSize.max,\n                    children:[\n                      InkWell(\n                        child: Icon(\n                            Icons.menu,\n                            color: Colors.white\n                        ),\n                        onTap: (){\n                          setState(() {\n                            if(isCollapsed)\n                              _controller.forward();\n …

我对 ReorderableListView 有一些问题。
我想从拖动的项目中删除背景（参见图片1 ）。我尝试在 ReorderableListView 周围添加主题小部件以解决此问题。它可以工作，但现在我的卡片侧面边框较浅（参见图2）您也可以在DarPad中尝试这个问题 您知道如何解决它吗？

这是我的代码：

Expanded(
  child: Theme(
    data: ThemeData(canvasColor: Colors.transparent),
    child: ReorderableListView(
      padding: const EdgeInsets.fromLTRB(16.0, 0.0, 16.0, 16.0),
      children: <Widget>[
        for (final items in homeButtons)
        Card(
          key: ValueKey(items),
          shape: RoundedRectangleBorder(
                        borderRadius: BorderRadius.circular(10.0)),
          child: Container(
            clipBehavior: Clip.antiAlias,
            alignment: Alignment.center,
            height: 50.0,
            width: double.infinity,
            decoration: BoxDecoration(
              gradient: const LinearGradient(
                colors: [
                  Color(0xFF3b474f),
                  Color(0xFF232b32),
                ],
                stops: [0, 1],
                begin: AlignmentDirectional(1, -1),
                end: AlignmentDirectional(-1, 1),
              ),
              borderRadius: BorderRadius.circular(10),
            ),
            child: ListTile(
              title: …

我正在使用 flutter 将图像上传到SQL 服务器，但出现错误：

类型“Null”不是“函数结果”的“文件”类型的子类型

这是我初始化文件的方式：

late File _image;

final picker=ImagePicker();

Future choiceImage() async{
 var pickedImage= await picker.getImage(source: ImageSource.gallery);
 setState(() {

  _image=File(pickedImage!.path);
});
}
 Future choice2Image() async{
   var pickedImage= await picker.getImage(source: ImageSource.camera);
  setState(() {
  _image=File(pickedImage!.path);
});
 }    

并通过以下方式获取此图像：

var pic =await http.MultipartFile.fromPath("image", _image.path);

不知道是什么问题？

flutter flutter Listview -> Container \'width\' 不起作用？

/示例/\n\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\ x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1\xe3\x85\xa1

scaffold \nbody : ListView\nchildren : [\n    Container (\n        width: 100, // Not Working \n        height: 100, // Ok\n        color: Colors.red.\n    ),\n]\n

!!! 但 ！！！

scaffold \nbody : ListView\nchildren : [\n    Stack(\n      children : [\n        Container (\n          width: 100, // OK\n          height: 100, // Ok\n          color: Colors.red.\n        ),\n    ]\n

为什么 ？？

1. 需要删除扩展图块小部件列表项的填充，请查找实际结果的图像。预期结果应消除顶部底部空间

这是代码，任何人都可以帮助我：

Theme(
      data: theme,
      child: ListTileTheme(
        contentPadding: EdgeInsets.all(0),
        dense: true,
        child: ExpansionTile(
          title: Row(
            mainAxisAlignment: MainAxisAlignment.start,
            children: [
              GFCheckbox(
                inactiveBgColor: kColorPrimaryDark,
                inactiveBorderColor: Colors.white,
                customBgColor: kColorPrimaryDark,
                size: 15,
                activeIcon: const Icon(
                  Icons.check,
                  size: 15,
                  color: Colors.white,
                ),
                activeBgColor: kColorPrimaryDark,
                onChanged: (value) {
                  setState(() {
                    isChecked = value;
                  });
                },
                value: isChecked,
                inactiveIcon: null,
              ),
              SizedBox(
                width: 5,
              ),
              textWidget(color: Colors.white, size: 12, text: root.title),
            ],
          ),
          key: PageStorageKey<DataList>(root),
          children: root.children.map(_buildTiles).toList(),
        ),
      ),
    );

现在我可以一次选择一项，但我想选择多项。我找到了一些用于多重选择的包，但想在不使用任何包的情况下实现。

  int? selectedIndex;
  final List<String> _wordName = [
    "Engaged in my Life",
    "Feel Alive",
    "Happy",
    "Love my Life",
  ];



GridView.builder(
                      scrollDirection: Axis.vertical,
                      gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                        crossAxisCount: 2,
                        crossAxisSpacing: 3,
                        mainAxisSpacing: 2,
                        childAspectRatio: (16 / 8),
                      ),
                      itemCount: _wordName.length,
                      itemBuilder: (context, index) {
                        return GestureDetector(
                          onTap: () {
                            setState(() {
                              print("now selected ===>>> $index");
                              selectedIndex = index;
                              showButton = true;
                            });
                          },
                          child: Container(
                            margin: EdgeInsets.all(10),
                            decoration: BoxDecoration(
                              color: selectedIndex == index
                                  ? Color(0xffDEB988).withOpacity(0.2)
                                  : Color(0xffF4F4F6).withOpacity(0.5),
                              borderRadius: BorderRadius.circular(5.0),
                              border: Border.all(
                                  color: …