isThreeLine property Null safety
final
Whether this list tile is intended to display three lines of text.
If true, then subtitle must be non-null (since it is expected to give the second and third lines of text).
If false, the list tile is treated as having one line if the subtitle is null and treated as having two lines if the subtitle is non-null.
When using a Text widget for title and subtitle, you can enforce line limits using Text.maxLines.
Implementation
final bool isThreeLine;