如何在此等待功能删除数据时添加加载屏幕？

Question

I want to add a loading screen when the screen pops and while it deletes the data from the firestore.

onPressed: () async {
                            Navigator.pop(context);
                            await Firestore.instance
                                .collection('projects')
                                .document(id)
                                .delete();
                            storage.ref().child(imagename).delete();
                          })

Answer 1

创建class

class LoaderDialog {

  static Future<void> showLoadingDialog(BuildContext context, GlobalKey key) async {
    var wid = MediaQuery.of(context).size.width / 2;
    return showDialog<void>(
        context: context,
        barrierDismissible: false,
        builder: (BuildContext context) {
          return Padding(
            padding: EdgeInsets.only(left: 130 , right: 130),
            child: Dialog(
              key: key,
              backgroundColor: Colors.white,
              child: Container(
                width: 60.0,
                height: 60.0,
                child:  Image.asset(
                  'images/loaderOld.gif',
                  height: 60,
                  width: 60,
                ),
              )
            ),
          );
        },
    );
  }
}

如何调用：在你的Class（你想显示加载程序的地方）。

final GlobalKey _LoaderDialog = new GlobalKey();

显示

LoaderDialog.showLoadingDialog(context, _LoaderDialog);

隐藏

   Navigator.of(_LoaderDialog.currentContext,rootNavigator: true).pop();

您可以添加任何 UI

如何在此等待功能删除数据时添加加载屏幕？

How to add Loading screen while this await function delete data?

future

async-await

dart

firebase

flutter