public abstract class

Layout

extends Object

java.lang.Object
↳	android.text.Layout

Known Direct Subclasses

BoringLayout, DynamicLayout, StaticLayout

Class Overview

A base class that manages text layout in visual elements on the screen.

For text that will be edited, use a DynamicLayout, which will be updated as the text changes. For text that will not change, use a StaticLayout.

Summary

Nested Classes
public abstract class	Layout.Alignment
public abstract class	Layout.Directions	Stores information about bidirectional (left-to-right or right-to-left) text within the layout of a line.

Constants
int	DIR_LEFT_TO_RIGHT
int	DIR_RIGHT_TO_LEFT

Protected Constructors
	Layout(CharSequence text, TextPaint paint, int width, Layout.Alignment align, float spacingmult, float spacingadd) Subclasses of Layout use this constructor to set the display text, width, and other standard properties.

Public Methods
void	draw(Canvas c) Draw this Layout on the specified Canvas.
void	draw(Canvas c, Path highlight, Paint highlightpaint, int cursorOffsetVertical) Draw the specified rectangle from this Layout on the specified Canvas, with the specified path drawn between the background and the text.
final Layout.Alignment	getAlignment() Return the base alignment of this layout.
abstract int	getBottomPadding() Returns the number of extra pixels of descent padding in the bottom line of the Layout.
void	getCursorPath(int point, Path dest, CharSequence editingBuffer) Fills in the specified Path with a representation of a cursor at the specified offset.
static float	getDesiredWidth(CharSequence source, int start, int end, TextPaint paint) Return how wide a layout would be necessary to display the specified text slice with one line per paragraph.
static float	getDesiredWidth(CharSequence source, TextPaint paint) Return how wide a layout would be necessary to display the specified text with one line per paragraph.
abstract int	getEllipsisCount(int line) Returns the number of characters to be ellipsized away, or 0 if no ellipsis is to take place.
abstract int	getEllipsisStart(int line) Return the offset of the first character to be ellipsized away, relative to the start of the line.
int	getEllipsizedWidth() Return the width to which this Layout is ellipsizing, or getWidth() if it is not doing anything special.
int	getHeight() Return the total height of this layout.
final int	getLineAscent(int line) Get the ascent of the text on the specified line.
final int	getLineBaseline(int line) Return the vertical position of the baseline of the specified line.
final int	getLineBottom(int line) Return the vertical position of the bottom of the specified line.
int	getLineBounds(int line, Rect bounds) Return the baseline for the specified line (0…getLineCount() - 1) If bounds is not null, return the top, left, right, bottom extents of the specified line in it.
abstract boolean	getLineContainsTab(int line) Returns whether the specified line contains one or more characters that need to be handled specially, like tabs or emoji.
abstract int	getLineCount() Return the number of lines of text in this layout.
abstract int	getLineDescent(int line) Return the descent of the specified line.
abstract Layout.Directions	getLineDirections(int line) Returns an array of directionalities for the specified line.
final int	getLineEnd(int line) Return the text offset after the last character on the specified line.
int	getLineForOffset(int offset) Get the line number on which the specified text offset appears.
int	getLineForVertical(int vertical) Get the line number corresponding to the specified vertical position.
float	getLineLeft(int line) Get the leftmost position that should be exposed for horizontal scrolling on the specified line.
float	getLineMax(int line) Gets the horizontal extent of the specified line, excluding trailing whitespace.
float	getLineRight(int line) Get the rightmost position that should be exposed for horizontal scrolling on the specified line.
abstract int	getLineStart(int line) Return the text offset of the beginning of the specified line.
abstract int	getLineTop(int line) Return the vertical position of the top of the specified line.
int	getLineVisibleEnd(int line) Return the text offset after the last visible character (so whitespace is not counted) on the specified line.
float	getLineWidth(int line) Gets the horizontal extent of the specified line, including trailing whitespace.
int	getOffsetForHorizontal(int line, float horiz) Get the character offset on the specfied line whose position is closest to the specified horizontal position.
int	getOffsetToLeftOf(int offset) Return the text offset that would be reached by moving left (possibly onto another line) from the specified offset.
int	getOffsetToRightOf(int offset) Return the text offset that would be reached by moving right (possibly onto another line) from the specified offset.
final TextPaint	getPaint() Return the base Paint properties for this layout.
final Layout.Alignment	getParagraphAlignment(int line) Get the alignment of the specified paragraph, taking into account markup attached to it.
abstract int	getParagraphDirection(int line) Returns the primary directionality of the paragraph containing the specified line.
final int	getParagraphLeft(int line) Get the left edge of the specified paragraph, inset by left margins.
final int	getParagraphRight(int line) Get the right edge of the specified paragraph, inset by right margins.
float	getPrimaryHorizontal(int offset) Get the primary horizontal position for the specified text offset.
float	getSecondaryHorizontal(int offset) Get the secondary horizontal position for the specified text offset.
void	getSelectionPath(int start, int end, Path dest) Fills in the specified Path with a representation of a highlight between the specified offsets.
final float	getSpacingAdd() Return the number of units of leading that are added to each line.
final float	getSpacingMultiplier() Return what the text height is multiplied by to get the line height.
final CharSequence	getText() Return the text that is displayed by this Layout.
abstract int	getTopPadding() Returns the (negative) number of extra pixels of ascent padding in the top line of the Layout.
final int	getWidth() Return the width of this layout.
final void	increaseWidthTo(int wid) Increase the width of this layout to the specified width.

Protected Methods
final boolean	isSpanned()

[Expand]

Inherited Methods

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Is called before the object's memory is being reclaimed by the VM.
final Class<? extends Object>	getClass() Returns the unique instance of Class which represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.

Constants

public static final int DIR_LEFT_TO_RIGHT

Constant Value: 1 (0x00000001)

public static final int DIR_RIGHT_TO_LEFT

Constant Value: -1 (0xffffffff)

Protected Constructors

protected Layout (CharSequence text, TextPaint paint, int width, Layout.Alignment align, float spacingmult, float spacingadd)

Subclasses of Layout use this constructor to set the display text, width, and other standard properties.

Public Methods

public void draw (Canvas c)

Draw this Layout on the specified Canvas.

public void draw (Canvas c, Path highlight, Paint highlightpaint, int cursorOffsetVertical)

Draw the specified rectangle from this Layout on the specified Canvas, with the specified path drawn between the background and the text.

public final Layout.Alignment getAlignment ()

Return the base alignment of this layout.

public abstract int getBottomPadding ()

Returns the number of extra pixels of descent padding in the bottom line of the Layout.

public void getCursorPath (int point, Path dest, CharSequence editingBuffer)

Fills in the specified Path with a representation of a cursor at the specified offset. This will often be a vertical line but can be multiple discontinous lines in text with multiple directionalities.

public static float getDesiredWidth (CharSequence source, int start, int end, TextPaint paint)

Return how wide a layout would be necessary to display the specified text slice with one line per paragraph.

public static float getDesiredWidth (CharSequence source, TextPaint paint)

Return how wide a layout would be necessary to display the specified text with one line per paragraph.

public abstract int getEllipsisCount (int line)

Returns the number of characters to be ellipsized away, or 0 if no ellipsis is to take place.

public abstract int getEllipsisStart (int line)

Return the offset of the first character to be ellipsized away, relative to the start of the line. (So 0 if the beginning of the line is ellipsized, not getLineStart().)

public int getEllipsizedWidth ()

Return the width to which this Layout is ellipsizing, or getWidth() if it is not doing anything special.

public int getHeight ()

Return the total height of this layout.

public final int getLineAscent (int line)

Get the ascent of the text on the specified line. The return value is negative to match the Paint.ascent() convention.

public final int getLineBaseline (int line)

Return the vertical position of the baseline of the specified line.

public final int getLineBottom (int line)

Return the vertical position of the bottom of the specified line.

public int getLineBounds (int line, Rect bounds)

Return the baseline for the specified line (0…getLineCount() - 1) If bounds is not null, return the top, left, right, bottom extents of the specified line in it.

Parameters

line	which line to examine (0..getLineCount() - 1)
bounds	Optional. If not null, it returns the extent of the line

Returns

the Y-coordinate of the baseline

public abstract boolean getLineContainsTab (int line)

Returns whether the specified line contains one or more characters that need to be handled specially, like tabs or emoji.

public abstract int getLineCount ()

Return the number of lines of text in this layout.

public abstract int getLineDescent (int line)

Return the descent of the specified line.

public abstract Layout.Directions getLineDirections (int line)

Returns an array of directionalities for the specified line. The array alternates counts of characters in left-to-right and right-to-left segments of the line.

public final int getLineEnd (int line)

Return the text offset after the last character on the specified line.

public int getLineForOffset (int offset)

Get the line number on which the specified text offset appears. If you ask for a position before 0, you get 0; if you ask for a position beyond the end of the text, you get the last line.

public int getLineForVertical (int vertical)

Get the line number corresponding to the specified vertical position. If you ask for a position above 0, you get 0; if you ask for a position below the bottom of the text, you get the last line.

public float getLineLeft (int line)

Get the leftmost position that should be exposed for horizontal scrolling on the specified line.

public float getLineMax (int line)

Gets the horizontal extent of the specified line, excluding trailing whitespace.

public float getLineRight (int line)

Get the rightmost position that should be exposed for horizontal scrolling on the specified line.

public abstract int getLineStart (int line)

Return the text offset of the beginning of the specified line. If the specified line is one beyond the last line, returns the end of the last line.

public abstract int getLineTop (int line)

Return the vertical position of the top of the specified line. If the specified line is one beyond the last line, returns the bottom of the last line.

public int getLineVisibleEnd (int line)

Return the text offset after the last visible character (so whitespace is not counted) on the specified line.

public float getLineWidth (int line)

Gets the horizontal extent of the specified line, including trailing whitespace.

public int getOffsetForHorizontal (int line, float horiz)

Get the character offset on the specfied line whose position is closest to the specified horizontal position.

public int getOffsetToLeftOf (int offset)

Return the text offset that would be reached by moving left (possibly onto another line) from the specified offset.

public int getOffsetToRightOf (int offset)

Return the text offset that would be reached by moving right (possibly onto another line) from the specified offset.

public final TextPaint getPaint ()

Return the base Paint properties for this layout. Do NOT change the paint, which may result in funny drawing for this layout.

public final Layout.Alignment getParagraphAlignment (int line)

Get the alignment of the specified paragraph, taking into account markup attached to it.

public abstract int getParagraphDirection (int line)

Returns the primary directionality of the paragraph containing the specified line.

public final int getParagraphLeft (int line)

Get the left edge of the specified paragraph, inset by left margins.

public final int getParagraphRight (int line)

Get the right edge of the specified paragraph, inset by right margins.

public float getPrimaryHorizontal (int offset)

Get the primary horizontal position for the specified text offset. This is the location where a new character would be inserted in the paragraph's primary direction.

public float getSecondaryHorizontal (int offset)

Get the secondary horizontal position for the specified text offset. This is the location where a new character would be inserted in the direction other than the paragraph's primary direction.

public void getSelectionPath (int start, int end, Path dest)

Fills in the specified Path with a representation of a highlight between the specified offsets. This will often be a rectangle or a potentially discontinuous set of rectangles. If the start and end are the same, the returned path is empty.

public final float getSpacingAdd ()

Return the number of units of leading that are added to each line.

public final float getSpacingMultiplier ()

Return what the text height is multiplied by to get the line height.

public final CharSequence getText ()

Return the text that is displayed by this Layout.

public abstract int getTopPadding ()

Returns the (negative) number of extra pixels of ascent padding in the top line of the Layout.

public final int getWidth ()

Return the width of this layout.

public final void increaseWidthTo (int wid)

Increase the width of this layout to the specified width. Be careful to use this only when you know it is appropriate -- it does not cause the text to reflow to use the full new width.

Interfaces

Classes

Enums