Migrating to v1

Each identifier removed before v1, and what to use instead. The - BREAKING: entries under Removed in CHANGELOG.md list the same removals. Deprecated identifiers that still exist, such as layout.Box.Render, are listed under Deprecated there.

Program options (package tui)

WithInput, WithOutput and WithErrOutput now take any io.Reader or io.Writer, file or not, so the separate options for non-file streams are gone. Option defaults are in program.md.

WithInputReader

Use WithInput. Given a reader that is not an *os.File, WithInput behaves as WithInputReader did: Run needs no terminal and doesn’t switch raw mode, and the Program quits when the reader returns io.EOF (TestWithInputPlainReaderNeedsNoTerminal). Given an *os.File, WithInput reads it as a terminal, and Run fails with a “not a terminal” error if it isn’t one (TestWithInputFileIsReadAsATerminal). To read a file as a plain stream instead, wrap it so it is no longer an *os.File, as the WithInput godoc shows (struct{ io.Reader }{f}).

A reader that also implements io.Closer is closed when the Program quits. WithInputCloser names a different closer to use instead.

WithOutputWriter

Use WithOutput. A writer that is not an *os.File, such as a bytes.Buffer, has no terminal size: the Program assumes 80x24 and never queries or resizes it. A ResizeMsg can still deliver another size.

WithErrWriter

Use WithErrOutput, which sets where Eprintln writes (default os.Stderr). Any io.Writer receives the text as it is.

WithLineRenderer

Use WithCellRenderer(false). The cell renderer is the default, and WithCellRenderer(false) selects the line renderer. See rendering.md for how the two differ.

String layout helpers (package layout)

The string join and grid helpers are replaced by Nodes. Wrap each pre-rendered string in layout.Block to make it a Node, then compose Nodes with Row, Column and GridNode. ExampleCrossAlign and ExampleGridNode in layout/example_test.go show the replacements in use, and layout.md covers sizing with FlexChild.

Box, Overlay and JoinHorizontalJustify still work on strings and are not removed.

JoinHorizontal

Use layout.Row(gap, children...), with one FlexChild per block.

JoinHorizontalAlign

Use layout.Row and set CrossAlign on each FlexChild: CrossStart, CrossCenter or CrossEnd. The zero value, CrossStretch, stretches the child to the row’s full height.

JoinVertical

Use layout.Column(gap, children...), with one FlexChild per block.

JoinVerticalAlign

Use layout.Column and set CrossAlign on each FlexChild, as for JoinHorizontalAlign. In a Column the cross axis is horizontal, so CrossStart keeps a child at its own width, flush left (ExampleColumn_crossStart).

FlexRow

Use layout.Row. Sizing that was set per item now goes in each child’s FlexChild fields (Basis, BasisLen, Grow, Shrink, Min, Max).

FlexItem

Use layout.FlexChild. The zero FlexChild is sized to its content and neither grows nor shrinks; layout.Fill(n) makes a child take the space left over.

Grid

Use layout.GridNode(tracks, gap, cells...). It takes one Track per column and fills cells row by row. GridNodeGaps gives rows and columns different gaps.

GridFlex

Use layout.GridNode. A Track with Grow > 0 shares the grid’s leftover width by weight, on top of the column’s content width.

ColSpec

Use layout.Track. The zero Track sizes the column to its widest cell, Size > 0 fixes the width, and Grow > 0 shares leftover width.