Allow passing alignment to BottomSheet

[BenjiFarquhar]

Can we pass in an alignment to the BottomSheet for use when it has constraints that make it not full width?

[exaby73]

Hello @BenjiFarquhar. Could you elaborate on the issue you are highlighting here and the proposed solution? Would be great if you could include code samples and screenshots as well. Thank you

[BenjiFarquhar]

Hi @exaby73. When we pass the constraints below to showModalBottomSheet, it displays a bottom sheet that is half of the screen width wide, that comes up from the bottom-center of the screen.

    final result = await showModalBottomSheet(
        context: context,
        constraints: BoxConstraints(
          maxWidth: MediaQuery.of(context).size.width / 2
        ),
        shape: const RoundedRectangleBorder(
            borderRadius: MODAL_BOTTOM_SHEET_RADIUS),
        builder: (context) => ManageImagesModalBottomSheet(widget.sizingInfo));

I want to position it at the bottom-right of the screen instead.

There is this code inside bottom_sheet.dart:

    if (constraints != null) {
      bottomSheet = Align(
        alignment: Alignment.bottomCenter,
        heightFactor: 1.0,
        child: ConstrainedBox(
          constraints: constraints,
          child: bottomSheet,
        ),
      );
    }

And when I replace Alignment.bottomCenter with Alignment.bottomRight in that source code file, I get the result I want. So I would like to pass alignment: Alignment.bottomRight into showModalBottomSheet() which would then be used in the code snippet above as a solution to this issue.

[exaby73]

Thanks for the detailed code sample and proposal :) Labelling the issue as this seems like a valid proposal

[HansMuller]

@esouthren - https://github.com/flutter/flutter/pull/116940 use size and alignment double values to scale and locate border edges. Maybe similar parameters could be used here? And for Snackbar?