Spannable Grid

 

The SpannableGrid is a Flutter widget that allows its cells to span columns and rows and supports moving cells inside the grid.

Features

• The widget is sized itself to fit its parent width and/or height
• The number of columns and rows is fixed
• Cells can span columns and rows
• Supports editing mode, in which cells can be moved inside the grid to available places
• Various editing strategies
• Styling the grid and its cells

Usage

In the dependencies: section of your pubspec.yaml, add the following line:

dependencies:
  spannable_grid: ^0.3.0

Import the package

import 'package:spannable_grid/spannable_grid.dart';

Create grid items

The SpannableGrid widget requires the list of SpannableGridCellData objects that define cells appearance.

    final cells = <SpannableGridCellData>[];
    cells.add(SpannableGridCellData(
      column: 1,
      row: 1,
      columnSpan: 2,
      rowSpan: 2,
      id: "Test Cell 1",
      child: Container(
        color: Colors.lime,
        child: Center(
          child: Text("Tile 2x2",
            style: Theme.of(context).textTheme.title,
          ),
        ),
      ),
    ));
    cells.add(SpannableGridCellData(
      column: 4,
      row: 1,
      columnSpan: 1,
      rowSpan: 1,
      id: "Test Cell 2",
      child: Container(
        color: Colors.lime,
        child: Center(
          child: Text("Tile 1x1",
            style: Theme.of(context).textTheme.title,
          ),
        ),
      ),
    ));

Add SpannableGrid widget

SpannableGrid(
  columns: 4,
  rows: 4,
  cells: cells,
  onCellChanged: (cell) { print('Cell ${cell.id} changed'); },
),

Editing mode

In the editing mode user can move cells to another empty place withing the grid.

Use editingStrategy parameter to define the behaviour in the editing mode. It has following options:

Name	Description
allowed	User can move the cells
enterOnLongTap	User should use a long tap on the cell to enter the editing mode
exitOnTap	When finished moving the cell, user should tap the cell to exit the editing mode
immediate	User can move cells immediately, just by starting dragging them
moveOnlyToNearby	The cell can be moved only to nearby empty cells

User can enter editing mode by long press on the cell.

In the editing mode the editing cell is highlighted, other cells are faded and the grid structure becomes visible. User can move editing cell to another available place inside the grid.

The updated cell is returned in onCellChanged callback.

Styling

Use the style parameter to style the appearance of the grid and its cells.

The following options are supported:

Name	Description
backgroundColor	It is used to display empty cells, when the emptyCellView parameter is not specified.
contentOpacity	It is used in the editing mode to make the content cells transparent, so the underlying grid structure becomes visible.
selectedCellDecoration	An additional decoration that is applied to the selected cell to highlight it in the editing mode.
spacing	A space between gird cells.

When the showGrid parameter is true the grid's structure is always visible. Otherwise it appears only in the editing mode.

Full example

You can find demo app in the example project.

More

Changelog

Please check the Changelog page for the latest version and changes.

License

Author: Evgeny Cherkasov.

This package is published under MIT License.

Contributions

Feel free to contribute to this project.

Flutter