pango.Layout

pango.Layout
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pango.Layout — an object representing a paragraph of text with attributes.

Synopsis

class pango.Layout(gobject.GObject):
    pango.Layout(context)
    def copy()
    def get_context()
    def set_attributes(attrs)
    def get_attributes()
    def set_text(text)
    def get_text()
    def set_markup(markup)
    def set_markup_with_accel(markup, accel_marker)
    def set_font_description(desc)
    def set_width(width)
    def get_width()
    def set_wrap(wrap)
    def get_wrap()
    def set_indent(indent)
    def get_indent()
    def set_spacing(spacing)
    def get_spacing()
    def set_justify(justify)
    def get_justify()
    def set_alignment(alignment)
    def get_alignment()
    def set_tabs(tabs)
    def get_tabs()
    def set_single_paragraph_mode(setting)
    def get_single_paragraph_mode()
    def context_changed()
    def index_to_pos(index)
    def get_cursor_pos(index)
    def move_cursor_visually(strong, old_index, old_trailing, direction)
    def xy_to_index(x, y)
    def get_extents()
    def get_pixel_extents()
    def get_size()
    def get_pixel_size()
    def get_line_count()
    def get_line(line)
    def get_iter()

Ancestry

+-- gobject.GObject
  +-- pango.Layout

Description

A pango.Layout object represents a paragraph of text with a pango.Context, a UTF-8 text string and a set of attributes for that string. The set of formatted lines can be extracted from the object, the layout can be rendered, and conversion between logical character positions within the layout's text, and the physical position of the resulting glyphs can be made. Also there are a number of attributes that adjust the formatting of the layout.

Constructor

    pango.Layout(context)

`context` :	a `pango.Context`
Returns :	a new `pango.Layout`.

Creates a new pango.Layout object with attributes initialized to the default values of the pango.Context specified by context.

Methods

pango.Layout.copy

    def copy()

Returns : a new pango.Layout that is a copy of the layout

The copy() method returns a pango.Layout that is a deep copy-by-value of the layout. The attribute list, tab array, and text from the layout are all copied by value.

pango.Layout.get_context

    def get_context()

Returns : the pango.Context for the layout.

The get_context() method returns the pango.Context used for this layout.

pango.Layout.set_attributes

    def set_attributes(attrs)

attrs : a pango.AttrList

The set_attributes() method sets the pango.AttrList for the layout object to the value specified by attrs.

pango.Layout.get_attributes

    def get_attributes()

Returns : a pango.AttrList

The get_attributes() method returns the pango.AttrList for the layout, if any.

pango.Layout.set_text

    def set_text(text)

text : a UTF8-string

The set_text() method sets the text of the layout to the value specified by text.

pango.Layout.get_text

    def get_text()

Returns :

the text in the layout

The get_text() method returns the text in the layout.

pango.Layout.set_markup

    def set_markup(markup)

markup : marked-up text

The set_markup() method is the same as the set_markup_with_accel() method but the markup text isn't scanned for accelerators.

pango.Layout.set_markup_with_accel

    def set_markup_with_accel(markup, accel_marker)

`markup` :	some marked-up text (see the Pango Markup Language reference page)
`accel_marker` :	marker for accelerators in the text
Returns :	the accelerator character if any

The set_markup_with_accel() method sets the layout text and attribute list from marked-up text to the value specified by markup_format (see the Pango Markup Language reference page). The current text and attribute list of the layout are replaced. If accel_marker is nonzero the markup will be parsed for the marker and the character following the first marker becomes the accelerator character. For example, if the accelerator marker is an underscore, the character after the first underscore will be the accelerator character. All characters marked as an accelerator will be displayed with a pango.UNDERLINE_LOW attribute, and the accelerator character will be returned in accel_char. A literal accel_marker character can be put in the markup by using two accel_marker characters together.

pango.Layout.set_font_description

    def set_font_description(desc)

desc : the new pango.FontDescription, or None to unset the current font description.

The set_font_description() method set the default pango.FontDescription for the layout to the value specified by desc. If no font description is set on the layout, the font description from the layout's context is used.

pango.Layout.set_width

    def set_width(width)

width : the desired width, or -1 to indicate that no wrapping should be performed.

The set_width() method sets the wrap width for the lines of the pango.Layout to the value specified by width. If the value of width is -1 no wrapping should be performed.

pango.Layout.get_width

    def get_width()

Returns :

the width

The get_width() method returns the width at which the lines of the pango.Layout should be wrapped.

pango.Layout.set_wrap

    def set_wrap(wrap)

wrap : the wrap mode

The set_wrap() method sets the wrap style to the value specified by wrap. The value of wrap must be one of:

`pango.WRAP_WORD`	Wrap lines at word boundaries.
`pango.WRAP_CHAR`	Wrap lines at character boundaries.

The wrap style is in effect if a width is set on the layout with the pango.Layout.set_width(). To turn off wrapping, set the width to -1.

pango.Layout.get_wrap

    def get_wrap()

Returns :

Active wrap mode.

The get_wrap() method returns the value of the wrap mode for the layout. See the set_wrap() method for more information.

pango.Layout.set_indent

    def set_indent(indent)

indent : the amount by which to indent

The set_indent() method sets the indentation of the first line of the layout to the value specified by indent. The value of indent may be negative to provide a hanging indent.

pango.Layout.get_indent

    def get_indent()

Returns :

the indent

The get_indent() method returns the amount of indentation of the first line of the layout.

pango.Layout.set_spacing

    def set_spacing(spacing)

spacing : the amount of spacing (in thousandths of a device unit)

The set_spacing() method sets the amount of spacing between the lines of the layout to the value specified by spacing.

pango.Layout.get_spacing

    def get_spacing()

Returns :

the spacing (in thousandths of a device unit)

The get_spacing() method returns the amount of spacing between the lines of the layout.

pango.Layout.set_justify

    def set_justify(justify)

justify : if TRUE the lines in the layout should be justified.

The set_justify() method sets the justification attribute to the value of justify. If justify is TRUE each complete line should be stretched to fill the entire width of the layout. This stretching is typically done by adding whitespace, but for some scripts (such as Arabic), the justification is done by extending the characters.

pango.Layout.get_justify

    def get_justify()

Returns : TRUE if justification will be used

The get_justify() method returns TRUE if each complete line should be stretched to fill the entire width of the layout.

pango.Layout.set_alignment

    def set_alignment(alignment)

alignment : the new alignment

The set_alignment() method sets the alignment (how partial lines are positioned within the horizontal space available) for the layout to the value specified by alignment. The value of alignment must be one of:

`pango.ALIGN_LEFT`	Put all available space on the right
`pango.ALIGN_CENTER`	Center the line within the available space
`pango.ALIGN_RIGHT`	Put all available space on the left

pango.Layout.get_alignment

    def get_alignment()

Returns :

the alignment value

The get_alignment() method returns the alignment (how partial lines are positioned within the horizontal space available) for the layout. See the set_alignment() method for more information.

pango.Layout.set_tabs

    def set_tabs(tabs)

tabs : a pango.TabArray

The set_tabs() method sets the tabs to the value specified by tabs thereby overriding the default tabs (every 8 spaces). If tabs is None, the default tabs are reinstated.

pango.Layout.get_tabs

    def get_tabs()

Returns : a copy of the tabs for this layout, or None

The get_tabs() method returns the current pango.TabArray used by this layout. If no pango.TabArray has been set, then the default tabs (every 8 spaces) are in use and None is returned

pango.Layout.set_single_paragraph_mode

    def set_single_paragraph_mode(setting)

setting : if TRUE newlines, etc. are not treated as paragraph separators.

The set_single_paragraph_mode() method sets the single paragraph mode attribute to the value specified by setting. If setting is TRUE, do not treat newlines and similar characters as paragraph separators; instead, keep all text in a single paragraph, and display a glyph for paragraph separator characters. Used when you want to allow editing of newlines on a single text line.

pango.Layout.get_single_paragraph_mode

    def get_single_paragraph_mode()

Returns : TRUE if the layout does not break paragraphs at paragraph separator characters

The get_single_paragraph_mode() method returns the value set by the set_single_paragraph_mode() method.

pango.Layout.context_changed

    def context_changed()

The context_changed() method forces recomputation of any state in the pango.Layout that might depend on the layout's context. This method should be called if you make changes to the pango.Context subsequent to creating the layout.

pango.Layout.index_to_pos

    def index_to_pos(index)

`index` :	byte index within the layout
Returns :	a 4-tuple representing the grapheme's position

The index_to_pos() method converts from the specified index within a pango.Layout to the onscreen position corresponding to the grapheme at that index, which is represented as a 4-tuple (x, y, width, height). Note that x is always the leading edge of the grapheme and x + width the trailing edge of the grapheme. If the directionality of the grapheme is right-to-left, then width will be negative.

pango.Layout.get_cursor_pos

    def get_cursor_pos(index)

`index` :	the byte index of the cursor
Returns :	a 2-tuple containing two 4-tuples representing the strong and weak cursor positions

The get_cursor_pos() method returns a 2-tuple containing two 4-tuples representing the strong and weak cursor positions of the specified index within a layout. The position of each cursor is stored as a zero-width rectangle represented by a 4-tuple (x, y, width, height). The strong cursor location is the location where characters of the directionality equal to the base direction of the layout are inserted. The weak cursor location is the location where characters of the directionality opposite to the base direction of the layout are inserted.

pango.Layout.move_cursor_visually

    def move_cursor_visually(strong, old_index, old_trailing, direction)

`strong` :	if `TRUE` the moving cursor is the strong cursor; otherwise, the weak cursor. The strong cursor is the cursor corresponding to text insertion in the base direction for the layout.
`old_index` :	the byte index of the grapheme for the old index
`old_trailing` :	if 0, the cursor was at the trailing edge of the grapheme indicated by `old_index`, if > 0, the cursor was at the leading edge.
`direction` :	direction to move cursor. A negative value indicates motion to the left.
Returns :	a 2-tuple containing: the new cursor byte index (a value of -1 indicates that the cursor has been moved off the beginning of the layout while a value of G_MAXINT indicates that the cursor has been moved off the end of the layout); and, the number of characters to move forward (from the new cursor position) to get the position where the cursor should be displayed.

The move_cursor_visually() returns a 2-tuple containing:

a new cursor position calculated from an old position (specified by old_index) and the specified direction to move visually
the number of characters to move forward (from the new cursor position) to get the position where the cursor should be displayed. This allows distinguishing the position at the beginning of one line from the position at the end of the preceding line. the first value is always on the line where the cursor should be displayed.

If direction is positive, then the new strong cursor position will be one position to the right of the old cursor position. If direction is negative then the new strong cursor position will be one position to the left of the old cursor position.

In the presence of bidirectional text, the correspondence between logical and visual order will depend on the direction of the current run, and there may be jumps when the cursor is moved off of the end of a run.

Motion here is in cursor positions, not in characters, so a single call to the move_cursor_visually() method may move the cursor over multiple characters when multiple characters combine to form a single grapheme.

pango.Layout.xy_to_index

    def xy_to_index(x, y)

`x` :	the X offset (in thousandths of a device unit) from the left edge of the layout.
`y` :	the Y offset (in thousandths of a device unit) from the top edge of the layout
Returns :	a 2-tuple containing the calculated byte index and an integer indicating where in the grapheme the user clicked (it will either be zero, or the number of characters in the grapheme - 0 represents the trailing edge of the grapheme).

The xy_to_index() method returns the byte index of the character at the specified x and y position within a layout. If the position is not inside the layout, the closest position is chosen (the (x, y) position will be clamped inside the layout).

pango.Layout.get_extents

    def get_extents()

Returns :

a 2-tuple containing two 4-tuples representing the as drawn and logical extents rectangles of the layout

The get_extents() method returns a 2-tuple containing two 4-tuples representing the ink and logical extents rectangles of the layout in device units (one pixel = pango.SCALE device units). Logical extents are usually what you want for positioning things. The extents are given in layout coordinates which begin at the top left corner of the layout.

pango.Layout.get_pixel_extents

    def get_pixel_extents()

Returns :

a 2-tuple containing two 4-tuples representing the as drawn (ink) and logical extents rectangles of the layout

The get_pixel_extents() method returns a 2-tuple containing two 4-tuples representing the logical and ink extents rectangles of the layout in pixel units. See the get_extents() method for more information. This method just calls the get_extents() and then converts the extents to pixels (one pixel = pango.SCALE device units).

pango.Layout.get_size

    def get_size()

Returns : a 2-tuple containing the logical width and height of the pango.Layout

The get_size() method returns a 2-tuple containing the logical width and height of the pango.Layout in pango device units (one pixel = pango.SCALE device units).

pango.Layout.get_pixel_size

    def get_pixel_size()

Returns : a 2-tuple containing the logical width height of the pango.Layout

The get_pixel_size() method returns a 2-tuple containing the logical width and height of the pango.Layout in pixels (one pixel = pango.SCALE device units). (The get_size() returns the width and height in device units.)

pango.Layout.get_line_count

    def get_line_count()

Returns :

the line count

The get_line_count() method returns the count of lines in the layout.

pango.Layout.get_line

    def get_line(line)

`line` :	the index of a line, which must be between 0 and layout.get_line_count() - 1, inclusive.
Returns :	the requested `pango.LayoutLine`, or `None` if the index is out of range.

Note

This method is available in PyGTK 2.8 and above.

The get_line() method returns the line with the index number specified by line from the layout. The returned layout line will become invalid if changes are made to the pango.Layout.

pango.Layout.get_iter

    def get_iter()

Returns : a new pango.LayoutIter object

Note

This method is available in PyGTK 2.6 and above.

The get_iter() method returns a pango.LayoutIter object that can be used to iterate over the visual extents of the layout.