Expand description
A model for text documents.
This model is thought as a backend for a text UI. TextDocument
can’t be modified directly by the user, only for setting the whole document with set_plain_text(...)
.
The user must use a TextCursor
using document.create_cursor()
to make any change.
§Document structure
§Elements
Frame
: contains Block elements and other Frame elements, formatable with FrameFormatBlock
: contains Text elements or Image elements, formatable with BlockFormatText
: contains the actuel text, formatable with TextFormatImage
: represent the position of an image, formatable with ImageFormat
All these items are encapsulated in its corresponding Element
for ease of storage.
§The simpler plain text
Frame
|- Block
|- Text
|- Block
|- Text
§The more complex rich text
Frame
|- Block
|- Text --> I really lo
|- Text --> ve (imagine it Formatted in bold)
|- Text --> Rust
|- Image
|- Text
|- Frame
|- Block
|- Text
|- Text
|- Text
|- Block
|- Text
|- Text
|- Text
|- Block
|- Image
§Signaling changes
Each modification is signaled using callbacks. TextDocument
offers different ways to make your code aware of any change:
-
TextDocument::add_text_change_callback()
Give the number of removed characters and number of added characters with the reference of a cursor position.
-
TextDocument::add_element_change_callback()
Give the modified element with the reason. If two direct children elements changed at the same time.
§Examples
use text_document::{TextDocument, ChangeReason, MoveMode};
let mut document = TextDocument::new();
document.add_text_change_callback(|position, removed_characters, added_characters|{
println!("position: {}, removed_characters: {}, added_characters: {}", position, removed_characters, added_characters);
} );
document.add_element_change_callback(|element, reason|{
assert_eq!(element.uuid(), 0);
assert_eq!(reason, ChangeReason::ChildrenChanged );
} );
document.set_plain_text("beginningend").unwrap();
let mut cursor = document.create_cursor();
cursor.set_position(9, MoveMode::MoveAnchor);
cursor.insert_plain_text("new\nplain_text\ntest");
Re-exports§
pub use crate::text_document::*;
pub use block::*;
pub use frame::*;
pub use image::*;
pub use text::*;
pub use text_cursor::*;