SpannableString
public class SpannableString
extends Object
implements CharSequence, GetChars, Spannable
java.lang.Object | |
↳ | android.text.SpannableString |
This is the class for text whose content is immutable but to which markup objects can be attached and detached. For mutable text, see SpannableStringBuilder
.
Summary
Inherited constants |
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Public constructors | |
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SpannableString(CharSequence source) For the backward compatibility reasons, this constructor copies all spans including |
Public methods | |
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final char | charAt(int i) Returns the |
boolean | equals(Object o) Indicates whether some other object is "equal to" this one. |
final void | getChars(int start, int end, char[] dest, int off) Exactly like String.getChars(): copy chars |
int | getSpanEnd(Object what) Return the end of the range of text to which the specified markup object is attached, or -1 if the object is not attached. |
int | getSpanFlags(Object what) Return the flags that were specified when |
int | getSpanStart(Object what) Return the beginning of the range of text to which the specified markup object is attached, or -1 if the object is not attached. |
<T> T[] | getSpans(int queryStart, int queryEnd, Class<T> kind) Return an array of the markup objects attached to the specified slice of this CharSequence and whose type is the specified type or a subclass of it. |
int | hashCode() Returns a hash code value for the object. |
final int | length() Returns the length of this character sequence. |
int | nextSpanTransition(int start, int limit, Class<T> kind) Return the first offset greater than |
void | removeSpan(Object what) Remove the specified object from the range of text to which it was attached, if any. |
void | setSpan(Object what, int start, int end, int flags) Attach the specified markup object to the range |
final CharSequence | subSequence(int start, int end) Returns a |
final String | toString() Returns a string representation of the object. |
static SpannableString | valueOf(CharSequence source) |
Inherited methods | |
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Public constructors
SpannableString
public SpannableString (CharSequence source)
For the backward compatibility reasons, this constructor copies all spans including NoCopySpan
.
Parameters | |
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source | CharSequence : source text |
Public methods
charAt
public final char charAt (int i)
Returns the char
value at the specified index. An index ranges from zero to length() - 1
. The first char
value of the sequence is at index zero, the next at index one, and so on, as for array indexing.
If the char
value specified by the index is a surrogate, the surrogate value is returned.
Parameters | |
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i | int : the index of the char value to be returned |
Returns | |
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char | the specified char value |
equals
public boolean equals (Object o)
Indicates whether some other object is "equal to" this one.
The equals
method implements an equivalence relation on non-null object references:
- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.
Parameters | |
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o | Object : This value may be null . |
Returns | |
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boolean | true if this object is the same as the obj argument; false otherwise. |
getChars
public final void getChars (int start, int end, char[] dest, int off)
Exactly like String.getChars(): copy chars start
through end - 1
from this CharSequence into dest
beginning at offset destoff
.
Parameters | |
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start | int |
end | int |
dest | char |
off | int |
getSpanEnd
public int getSpanEnd (Object what)
Return the end of the range of text to which the specified markup object is attached, or -1 if the object is not attached.
Parameters | |
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what | Object |
Returns | |
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int |
getSpanFlags
public int getSpanFlags (Object what)
Return the flags that were specified when Spannable.setSpan
was used to attach the specified markup object, or 0 if the specified object has not been attached.
Parameters | |
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what | Object |
Returns | |
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int |
getSpanStart
public int getSpanStart (Object what)
Return the beginning of the range of text to which the specified markup object is attached, or -1 if the object is not attached.
Parameters | |
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what | Object |
Returns | |
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int |
getSpans
public T[] getSpans (int queryStart, int queryEnd, Class<T> kind)
Return an array of the markup objects attached to the specified slice of this CharSequence and whose type is the specified type or a subclass of it. Specify Object.class for the type if you want all the objects regardless of type.
Parameters | |
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queryStart | int |
queryEnd | int |
kind | Class |
Returns | |
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T[] |
hashCode
public int hashCode ()
Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap
.
The general contract of hashCode
is:
- Whenever it is invoked on the same object more than once during an execution of a Java application, the
hashCode
method must consistently return the same integer, provided no information used inequals
comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equals
method, then calling thehashCode
method on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal according to the
equals
method, then calling thehashCode
method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns | |
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int | a hash code value for this object. |
length
public final int length ()
Returns the length of this character sequence. The length is the number of 16-bit char
s in the sequence.
Returns | |
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int | the number of char s in this sequence |
nextSpanTransition
public int nextSpanTransition (int start, int limit, Class<T> kind)
Return the first offset greater than start
where a markup object of class type
begins or ends, or limit
if there are no starts or ends greater than start
but less than limit
. Specify null
or Object.class for the type if you want every transition regardless of type.
Parameters | |
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start | int |
limit | int |
kind | Class |
Returns | |
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int |
removeSpan
public void removeSpan (Object what)
Remove the specified object from the range of text to which it was attached, if any. It is OK to remove an object that was never attached in the first place.
Parameters | |
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what | Object |
setSpan
public void setSpan (Object what, int start, int end, int flags)
Attach the specified markup object to the range start…end
of the text, or move the object to that range if it was already attached elsewhere. See Spanned
for an explanation of what the flags mean. The object can be one that has meaning only within your application, or it can be one that the text system will use to affect text display or behavior. Some noteworthy ones are the subclasses of CharacterStyle
and ParagraphStyle
, and TextWatcher
and SpanWatcher
.
Parameters | |
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what | Object |
start | int |
end | int |
flags | int |
subSequence
public final CharSequence subSequence (int start, int end)
Returns a CharSequence
that is a subsequence of this sequence. The subsequence starts with the char
value at the specified index and ends with the char
value at index end - 1
. The length (in char
s) of the returned sequence is end - start
, so if start == end
then an empty sequence is returned.
Parameters | |
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start | int : the start index, inclusive |
end | int : the end index, exclusive |
Returns | |
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CharSequence | the specified subsequence |
toString
public final String toString ()
Returns a string representation of the object.
Returns | |
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String | a string representation of the object. |
valueOf
public static SpannableString valueOf (CharSequence source)
Parameters | |
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source | CharSequence |
Returns | |
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SpannableString |