Android
android.text
public abstract class

android.text.Layout

java.lang.Object
android.text.Layout

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.

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

Summary

Constants

      Value  
int  DIR_LEFT_TO_RIGHT    0x00000001 
int  DIR_RIGHT_TO_LEFT    -1  0xffffffff 

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 tabs.
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()
Methods inherited from class java.lang.Object

Details

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 tabs.

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.

Protected Methods

protected final boolean isSpanned()

Copyright 2007 Google Inc. Build 0.9_r1-98467 - 14 Aug 2008 18:48