DynamicDrawableSpan
public
abstract
class
DynamicDrawableSpan
extends ReplacementSpan
java.lang.Object | ||||
↳ | android.text.style.CharacterStyle | |||
↳ | android.text.style.MetricAffectingSpan | |||
↳ | android.text.style.ReplacementSpan | |||
↳ | android.text.style.DynamicDrawableSpan |
Span that replaces the text it's attached to with a Drawable
that can be aligned with
the bottom or with the baseline of the surrounding text.
For an implementation that constructs the drawable from various sources (Bitmap
,
Drawable
, resource id or Uri
) use ImageSpan
.
A simple implementation of DynamicDrawableSpan
that uses drawables from resources
looks like this:
class MyDynamicDrawableSpan extends DynamicDrawableSpan { private final Context mContext; private final int mResourceId; public MyDynamicDrawableSpan(Context context, @DrawableRes int resourceId) { mContext = context; mResourceId = resourceId; } @Override public Drawable getDrawable() { Drawable drawable = mContext.getDrawable(mResourceId); drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight()); return drawable; } }
SpannableString string = new SpannableString("Text with a drawable span"); string.setSpan(new MyDynamicDrawableSpan(context, R.mipmap.ic_launcher), 12, 20, Spanned .SPAN_EXCLUSIVE_EXCLUSIVE);
Summary
Constants | |
---|---|
int |
ALIGN_BASELINE
A constant indicating that the bottom of this span should be aligned with the baseline of the surrounding text. |
int |
ALIGN_BOTTOM
A constant indicating that the bottom of this span should be aligned with the bottom of the surrounding text, i.e., at the same level as the lowest descender in the text. |
int |
ALIGN_CENTER
A constant indicating that this span should be vertically centered between the top and the lowest descender. |
Fields | |
---|---|
protected
final
int |
mVerticalAlignment
|
Public constructors | |
---|---|
DynamicDrawableSpan()
Creates a |
Protected constructors | |
---|---|
DynamicDrawableSpan(int verticalAlignment)
Creates a |
Public methods | |
---|---|
void
|
draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint)
Draws the span into the canvas. |
abstract
Drawable
|
getDrawable()
Your subclass must implement this method to provide the bitmap to be drawn. |
int
|
getSize(Paint paint, CharSequence text, int start, int end, Paint.FontMetricsInt fm)
Returns the width of the span. |
int
|
getVerticalAlignment()
Returns the vertical alignment of this span, one of |
String
|
toString()
Returns a string representation of the object. |
Inherited methods | |
---|---|
Constants
ALIGN_BASELINE
public static final int ALIGN_BASELINE
A constant indicating that the bottom of this span should be aligned with the baseline of the surrounding text.
Constant Value: 1 (0x00000001)
ALIGN_BOTTOM
public static final int ALIGN_BOTTOM
A constant indicating that the bottom of this span should be aligned with the bottom of the surrounding text, i.e., at the same level as the lowest descender in the text.
Constant Value: 0 (0x00000000)
ALIGN_CENTER
public static final int ALIGN_CENTER
A constant indicating that this span should be vertically centered between the top and the lowest descender.
Constant Value: 2 (0x00000002)
Fields
Public constructors
DynamicDrawableSpan
public DynamicDrawableSpan ()
Creates a DynamicDrawableSpan
. The default vertical alignment is
ALIGN_BOTTOM
Protected constructors
DynamicDrawableSpan
protected DynamicDrawableSpan (int verticalAlignment)
Creates a DynamicDrawableSpan
based on a vertical alignment.\
Parameters | |
---|---|
verticalAlignment |
int : one of ALIGN_BOTTOM , ALIGN_BASELINE or
ALIGN_CENTER
Value is ALIGN_BOTTOM , ALIGN_BASELINE , or ALIGN_CENTER |
Public methods
draw
public void draw (Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint)
Draws the span into the canvas.
Parameters | |
---|---|
canvas |
Canvas : This value cannot be null . |
text |
CharSequence : Current text. |
start |
int : Value is 0 or greater |
end |
int : Value is 0 or greater |
x |
float : Edge of the replacement closest to the leading margin. |
top |
int : Top of the line. |
y |
int : Baseline. |
bottom |
int : Bottom of the line. |
paint |
Paint : This value cannot be null . |
getDrawable
public abstract Drawable getDrawable ()
Your subclass must implement this method to provide the bitmap to be drawn. The dimensions of the bitmap must be the same from each call to the next.
Returns | |
---|---|
Drawable |
getSize
public int getSize (Paint paint, CharSequence text, int start, int end, Paint.FontMetricsInt fm)
Returns the width of the span. Extending classes can set the height of the span by updating
attributes of Paint.FontMetricsInt
. If the span covers the whole
text, and the height is not set,
draw(android.graphics.Canvas, java.lang.CharSequence, int, int, float, int, int, int, android.graphics.Paint)
will not be
called for the span.
Parameters | |
---|---|
paint |
Paint : This value cannot be null . |
text |
CharSequence : Current text. |
start |
int : Value is 0 or greater |
end |
int : Value is 0 or greater |
fm |
Paint.FontMetricsInt : This value may be null . |
Returns | |
---|---|
int |
Width of the span. |
getVerticalAlignment
public int getVerticalAlignment ()
Returns the vertical alignment of this span, one of ALIGN_BOTTOM
,
ALIGN_BASELINE
or ALIGN_CENTER
.
Returns | |
---|---|
int |
Value is ALIGN_BOTTOM , ALIGN_BASELINE , or ALIGN_CENTER |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
---|---|
String |
a string representation of the object. |