watson / virtual-grid

A viewport into a virtual grid of text cells

virtual-grid

A viewport into a virtual grid of text cells.

Renderes cells in a grid. Each cell contains text that is wrapped and truncated to fit inside the cell. Full support for ANSI colors. Useful as a layout manager for terminal apps.

Installation

npm install virtual-grid --save

Usage

const Grid = require('virtual-grid')

const grid = new Grid({
  height: 10,
  width: 20,
  rows: [
    [{height: 5, text: 'This is the top cell spanning the entire width'}],
    [{width: '50%', text: 'Left column'}, {width: '50%', text: 'Right column'}]
  ]
})

// Update the text in cell C
grid.update(1, 1, 'This text have been overwritten')

console.log(grid.toString())

Output:

This is the top cell
spanning the entire
width


Left      This text
column    have been
          overwritt…

API

grid = new Grid(options)

Provide an options object as the first argument. The following options are supported:

• width - The total width of the viewport (defaults to process.stdout.columns)
• height - The total height of the viewport (defaults to process.stdout.rows)
• rows - An array of rows. Each row is an array of cell objects

A cell object supports the following properties:

• width - The width of the cell. If the value is the string auto it will fill out the remaining space in the viewport. If the value is a string containing a percent sign (e.g. 25%), it's treated as a percentage of the total width of the viewport. Otherwise it's treated as an integer representing the width in columns (defaults to auto)
• height - The height of the cell. If the value is the string auto it will fill out the remaining space in the viewport. If the value is a string containing a percent sign (e.g. 25%), it's treated as a percentage of the total height of the viewport. Otherwise it's treated as an integer representing the height in rows (defaults to auto)
• text - Default text content of the cell (defaults to an empty string)
• wrap - Set to false to disable automatic line wrapping (defaults to true)
• padding - An optional array of cell padding for the top, right, bottom, and left edge of the cell respectively, e.g. [0, 2, 0, 2] for 2 chars of padding on the left and right edge only. If given an integer instead of an array, the padding is applied to all edges

You can use strings instead of objects for cells. This is equivalent to {text: cell}

grid = new Grid(rows)

An alias for:

new Grid({rows: rows})

Event: update

Emitted every time a cell in the grid is updated.

grid.update(row, cell, text)

Update the text content of a cell.

Arguments:

• row - The row index
• cell - The cell index inside the row
• text - The new text content of the cell

grid.resize(width, height)

Resize the viewport to new width and height.

cell = grid.cellAt(row, index)

Return the cell at the gien row and index`.

str = grid.toString()

Render all content in all cells in the grid and return the result as one big string.

License

MIT