NAME

Prima::Edit - standard text editing widget

SYNOPSIS

        use Prima qw(Edit Application);
        my $e = Prima::Edit->new(
                text         => 'Hello $world',
                syntaxHilite => 1,
        );
        run Prima;

DESCRIPTION

The class provides text editing capabilities, three types of selection, text wrapping, syntax highlighting, auto indenting, undo and redo function, search and replace methods.

The module declares "bt::" package, that contains integer constants for selection block type, used by blockType property.

USAGE

The text is stored line-wise in "{lines}" array; to access it use get_line method. To access the text chunk-wise, use get_chunk method.

All keyboard events, except the character input and tab key handling, are processed by the accelerator table ( see Prima::Menu ). The default "accelItems" table defines names, keyboard combinations, and the corresponding actions to the class functions. The class does not provide functionality to change these mappings. To do so, consult "Prima::AccelTable" in Prima::Menu.

Coordinates

The class addresses the text space by (X,Y)-coordinates, where X is visual cluster offset and Y is line number. The addressing can be 'visual' and 'logical', - in logical case Y is number of line of text. The difference can be observed if wordWrap property is set to 1, when a single text string can be shown as several sub-strings, called chunks.

Cluster shaping and word wrapping can play a role here. Consider f.ex. text "offset is zero", that for the sake of the example can wrapped by width and displayed as two lines, "offset" and "is zero". Here, the font substitutes "ff" text with a single ligature glyph. Here, for example, coord("f") will be (0,1) in all coordinates, but coord("z") is different:

Physical: X coordinate is a character offset from character line number Y. These coordinates are identical with and without "wordWrap" flag. This coordinate is used for direct text manipulation.
Example: coord("z") is (0,10);
Visual: X coordinate is a glyph cluster offset from character line number Y. These coordinates are identical with and without "wordWrap" flag. This coordinate is used for cursor and selection API.
Example: coord("z") is (0,9);
Logical: Y coordinates is a wrapped line index. "chunkMap" internal array is addresses in logical coordinates. X coordinate is a glyph cluster offset from the line start. This coordinate is used mostly internally.
Example: coord("z") is (1,3);

API

Events

ParseSyntax TEXT, RESULT_ARRAY_REF: Called when syntax highlighting is requires - TEXT is a string to be parsed, and the parsing results to be stored in RESULT_ARRAY_REF, which is a reference to an array of integer pairs, each representing a single-colored text chunk. The first integer in the pairs is the length of a chunk, the second - color value ( "cl::XXX" constants ).

Properties

autoIndent BOOLEAN: Selects if the auto indenting feature is on.
Default value: 1
blockType INTEGER: Defines type of selection block. Can be one of the following constants:

bt::CUA

Normal block, where the first and the last line of the selection can be partial, and the lines between occupy the whole line. CUA stands for 'common user access'.

Default keys: Shift + arrow keys

See also: mark_horizontal

cursor X, Y

Selects visual position of the cursor

cursorX X

Selects visual horizontal position of the cursor

cursorY Y

Selects visual vertical position of the cursor

cursorWrap BOOLEAN

Selects cursor behavior when moved horizontally outside the line. If 0, the cursor is not moved. If 1, the cursor moved to the adjacent line.

See also: cursor_left, cursor_right, word_left, word_right.

insertMode BOOLEAN

Governs the typing mode - if 1, the typed text is inserted, if 0, the text overwrites the old text. When "insertMode" is 0, the cursor shape is thick and covers the whole character; when 1, it is of default width.

Default toggle key: Insert

hiliteNumbers COLOR

Selects the color for number highlighting

hiliteQStrings COLOR

Selects the color for highlighting the single-quoted strings

hiliteQQStrings COLOR

Selects the color for highlighting the double-quoted strings

hiliteIDs ARRAY

Array of scalar pairs, that define words to be highlighted. The first item in the pair is an array of words; the second item is a color value.

hiliteChars ARRAY

Array of scalar pairs, that define characters to be highlighted. The first item in the pair is a string of characters; the second item is a color value.

hiliteREs ARRAY

Array of scalar pairs, that define character patterns to be highlighted. The first item in the pair is a perl regular expression; the second item is a color value.

Note: these are tricky. Generally, they assume that whatever is captured in (), is highlighted, and that capturing parentheses match from the first character onwards. So for simple matches like " (\d+) " (digits) or " (#.*) " this works fine. Things become more interesting if you need to check text after, or especially before the capture. For this you need to make sure that whatever text is matched by a regexp, need not move "pos" pointer as the regexes are looped over with "\G" anchor prepended (i.e. starting each time from the position the previous regex left off), and with "/gc" flags (advancing " pos " to the match length). Advancing the "pos" will skip color highlighting on text after the capture but before end of the match - so you'll need look-ahead assertions, " (?=pattern) " and " (?!pattern) " (see "Lookaround Assertions" in perlre ).

For example, we have a string " ABC123abc ", and we want to match 123 followed by abc. This won't work

        hiliteREs => [
                '(123)abc',cl::LightRed,
                '(abc)', cl::LightGreen 
        ]

while this will:

        hiliteREs => [
                '(123)(?=abc)',cl::LightRed,
                '(abc)', cl::LightGreen 
        ]

If you need to look behind, the corresponding assertions " (?<=pattern) " and " (?<!pattern) " could be used, but these are even more restrictive in that they only support fixed-width looks-behinds (NB: " \K " won't work because of " \G " either). That way, if we want to match 123 that follow ABC, this won't work:

        hiliteREs =>  [
                '(ABC)',cl::LightBlue,
                '(?<=[ABC]+)(123)',cl::LightRed,
        ]

while this will:

        hiliteREs =>  [
                '(ABC)',cl::LightBlue,
                '(?<=[ABC]{3})(123)',cl::LightRed,
        ]

mark MARK [ BLOCK_TYPE ]

Selects block marking state. If MARK is 1, starts the block marking, if 0 - stops the block marking. When MARK is 1, BLOCK_TYPE can be used to set the selection type ( "bt::XXX" constants ). If BLOCK_TYPE is unset the value of blockType is used.

markers ARRAY

Array of arrays with integer pairs, X and Y, where each represents a visual coordinates in text. Used as anchor storage for fast navigation.

Methods

add_marker X, Y: Adds visual coordinated X,Y to markers property.
back_char [ REPEAT = 1 ]: Removes REPEAT times a character left to the cursor. If the cursor is on 0 x-position, removes the new-line character and concatenates the lines.
Default key: Backspace
cancel_block: Removes the selection block
Default key: Alt+U
change_locked: Returns 1 if the logical locking is on, 0 if it is off.
See also lock_change.
copy: Copies the selected text, if any, to the clipboard.
Default key: Ctrl+Insert
copy_block: Copies the selected text and inserts it into the cursor position, according to the blockType value.
Default key: Alt+C
cursor_cend: Moves cursor to the bottom line
Default key: Ctrl+End
cursor_chome: Moves cursor to the top line
Default key: Ctrl+Home
cursor_cpgdn: Default key: Ctrl+PageDown
Moves cursor to the end of text.
cursor_cpgup: Moves cursor to the beginning of text.
Default key: Ctrl+PageUp
cursor_down [ REPEAT = 1 ]: Moves cursor REPEAT times down
Default key: Down
cursor_end: Moves cursor to the end of the line
Default key: End
cursor_home: Moves cursor to the beginning of the line
Default key: Home
cursor_left [ REPEAT = 1 ]: Moves cursor REPEAT times left
Default key: Left
cursor_right [ REPEAT = 1 ]: Moves cursor REPEAT times right
Default key: Right
cursor_up [ REPEAT = 1 ]: Moves cursor REPEAT times up
Default key: Up
cursor_pgdn [ REPEAT = 1 ]: Moves cursor REPEAT pages down
Default key: PageDown
cursor_pgup [ REPEAT = 1 ]: Moves cursor REPEAT pages up
Default key: PageUp
cursor_shift_key [ ACCEL_TABLE_ITEM ]: Performs action of the cursor movement, bound to ACCEL_TABLE_ITEM action ( defined in "accelTable" or "accelItems" property ), and extends the selection block along the cursor movement. Not called directly.
cut: Cuts the selected text into the clipboard.
Default key: Shift+Delete
delete_block: Removes the selected text.
Default key: Alt+D
delete_char [ REPEAT = 1 ]: Delete REPEAT characters from the cursor position
Default key: Delete
delete_line LINE_ID, [ LINES = 1 ]: Removes LINES of text at LINE_ID.
delete_current_chunk: Removes the chunk ( or line, if wordWrap is 0 ) at the cursor.
Default key: Ctrl+Y
delete_chunk CHUNK_ID, [ CHUNKS = 1 ]: Removes CHUNKS ( or lines, if wordWrap is 0 ) of text at CHUNK_ID
delete_marker INDEX: Removes marker INDEX in markers list.
delete_to_end: Removes text to the end of the chunk.
Default key: Ctrl+E
delete_text X, Y, TEXT_LENGTH: Removes TEXT_LENGTH characters at X,Y physical coordinates
draw_colorchunk CANVAS, LINE_ID, X, Y, COLOR: Paints the syntax-highlighted chunk taken from LINE_ID line index, at X, Y. COLOR is used if the syntax highlighting information contains "cl::Fore" as color reference.
end_block: Stops the block selection session.
find SEARCH_STRING, [ X = 0, Y = 0, REPLACE_LINE = '', OPTIONS ]: Tries to find ( and, if REPLACE_LINE is defined, to replace with it ) SEARCH_STRING from (X,Y) visual coordinates. OPTIONS is an integer that consists of the "fdo::" constants; the same constants are used in Prima::Dialog::FindDialog, which provides graphic interface to the find and replace facilities of Prima::Edit.
Returns X1, Y, X2, NEW_STRING where X1.Y-X2.Y are visual coordinates of the found string, and NEW_STRING is the replaced version (if any)

fdo::MatchCase: If set, the search is case-sensitive.
fdo::WordsOnly: If set, SEARCH_STRING must constitute the whole word.
fdo::RegularExpression: If set, SEARCH_STRING is a regular expression.
fdo::BackwardSearch: If set, the search direction is backwards.
fdo::ReplacePrompt: Not used in the class, however, used in Prima::Dialog::FindDialog.

get_chunk CHUNK_ID: Returns chunk of text, located at CHUNK_ID. Returns empty string if chunk is nonexistent.
get_chunk_width TEXT, FROM, LENGTH, [ RETURN_TEXT_PTR ]: Returns the width in pixels of "substr( TEXT, FROM, LENGTH)". If FROM is larger than length of TEXT, TEXT is padded with space characters. Tab character in TEXT replaced to tabIndent times space character. If RETURN_TEXT_PTR pointer is specified, the converted TEXT is stored there.
get_line INDEX: Returns line of text, located at INDEX. Returns empty string if line is nonexistent.
get_line_dimension INDEX: Returns two integers, representing the line at INDEX in wordWrap mode: the first value is the corresponding chunk index, the second is how many chunks represent the line.
See also: physical_to_logical.
get_selected_text: Return the text currently selected.
has_selection: Returns boolean value, indicating if the selection block is active.
insert_empty_line LINE_ID, [ REPEAT = 1 ]: Inserts REPEAT empty lines at LINE_ID.
insert_line LINE_ID, @TEXT: Inserts @TEXT strings at LINE_ID
insert_text TEXT, [ HIGHLIGHT = 0 ]: Inserts TEXT at the cursor position. If HIGHLIGHT is set to 1, the selection block is cancelled and the newly inserted text is selected.
lock_change BOOLEAN: Increments ( 1 ) or decrements ( 0 ) lock count. Used to defer change notification in multi-change calls. When internal lock count hits zero, "Change" notification is called.
physical_to_logical X, Y: Maps visual X,Y coordinates to the logical and returns the integer pair. Returns same values when wordWrap is 0.
logical_to_visual X, Y: Maps logical X,Y coordinates to the visual and returns the integer pair.
Returns same values when wordWrap is 0.
visual_to_physical X, Y: Maps visual X,Y coordinates to the physical text offset relative to the Y line
Returns same X when the line does not contain any right-to-left characters or complex glyphs.
physical_to_visual X, Y: Maps test offset X from line Y to the visual X coordinate.
Returns same X when the line does not contain any right-to-left characters or complex glyphs.
mark_horizontal: Starts block marking session with "bt::Horizontal" block type.
Default key: Alt+L
mark_vertical: Starts block marking session with "bt::Vertical" block type.
Default key: Alt+B
overtype_block: Copies the selected text and overwrites the text next to the cursor position, according to the blockType value.
Default key: Alt+O
paste: Copies text from the clipboard and inserts it in the cursor position.
Default key: Shift+Insert
realize_panning: Performs deferred widget panning, activated by setting "{delayPanning}" to 1. The deferred operations are those performed by offset and topLine.
set_line LINE_ID, TEXT, [ OPERATION, FROM, LENGTH ]: Changes line at LINE_ID to new TEXT. Hint scalars OPERATION, FROM and LENGTH used to maintain selection and marking data. OPERATION is an arbitrary string, the ones that are recognized are 'overtype', 'add', and 'delete'. FROM and LENGTH define the range of the change; FROM is a cluster offset and LENGTH is a length of changed text.
split_line: Splits a line in two at the cursor position.
Default key: Enter ( or Ctrl+Enter if wantReturns is 0 )
select_all: Selects all text
start_block [ BLOCK_TYPE ]: Begins the block selection session. The block type if BLOCK_TYPE, if it is specified, or blockType property value otherwise.
update_block: Adjusts the selection inside the block session, extending of shrinking it to the current cursor position.
word_left [ REPEAT = 1 ]: Moves cursor REPEAT words to the left.
word_right [ REPEAT = 1 ]: Moves cursor REPEAT words to the right.

AUTHOR

Dmitry Karasik, <dmitry@karasik.eu.org>.