android.text
public abstract class
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 | 1 | 0x00000001 | |
| int | DIR_RIGHT_TO_LEFT | -1 | 0xffffffff |
Protected Constructors
| Layout(CharSequence text, TextPaint paint, int width, 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 hilite, Paint hilitepaint) | ||||
| Draw the specified rectangle from this Layout on the specified Canvas, with the specified path drawn between the background and the text. | |||||
| final | 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. | |||||
| 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 | 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) | ||||
| Get the horizontal extent of the specified line. | |||||
| 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. | |||||
| 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 | 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, 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 hilite, Paint hilitepaint)
Draw the specified rectangle from this Layout on the specified Canvas,
with the specified path drawn between the background and the text.
public final 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 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 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)
Get the horizontal extent of the specified line.
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 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 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.