# PrecomputedText
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
Summary:[Nested Classes](https://developer.android.com/reference/android/text/PrecomputedText#nestedclasses)\|[Inherited Constants](https://developer.android.com/reference/android/text/PrecomputedText#inhconstants)\|[Methods](https://developer.android.com/reference/android/text/PrecomputedText#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/android/text/PrecomputedText#inhmethods)
# PrecomputedText
*** ** * ** ***
[Kotlin](https://developer.android.com/reference/kotlin/android/text/PrecomputedText "View this page in Kotlin")\|Java
`
public
class
PrecomputedText
`
`
extends `[Object](https://developer.android.com/reference/java/lang/Object)`
``
implements
`[Spannable](https://developer.android.com/reference/android/text/Spannable)`
`
|---|------------------------------|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.text.PrecomputedText |
*** ** * ** ***
A text which has the character metrics data. A text object that contains the character metrics data and can be used to improve the performance of text layout operations. When a PrecomputedText is created with a given[CharSequence](https://developer.android.com/reference/java/lang/CharSequence), it will measure the text metrics during the creation. This PrecomputedText instance can be set on[TextView](https://developer.android.com/reference/android/widget/TextView)or[StaticLayout](https://developer.android.com/reference/android/text/StaticLayout). Since the text layout information will be included in this instance,[TextView](https://developer.android.com/reference/android/widget/TextView)or[StaticLayout](https://developer.android.com/reference/android/text/StaticLayout)will not have to recalculate this information. Note that the[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText)created from different parameters of the target[TextView](https://developer.android.com/reference/android/widget/TextView)will be rejected internally and compute the text layout again with the current[TextView](https://developer.android.com/reference/android/widget/TextView)parameters.
An example usage is:
static void asyncSetText(TextView textView, final String longString, Executor bgExecutor) {
// construct precompute related parameters using the TextView that we will set the text on.
final PrecomputedText.Params params = textView.getTextMetricsParams();
final Reference textViewRef = new WeakReference<>(textView);
bgExecutor.submit(() -> {
TextView textView = textViewRef.get();
if (textView == null) return;
final PrecomputedText precomputedText = PrecomputedText.create(longString, params);
textView.post(() -> {
TextView textView = textViewRef.get();
if (textView == null) return;
textView.setText(precomputedText);
});
});
}
Note that the[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText)created from different parameters of the target[TextView](https://developer.android.com/reference/android/widget/TextView)will be rejected. Note that any[NoCopySpan](https://developer.android.com/reference/android/text/NoCopySpan)attached to the original text won't be passed to PrecomputedText.
## Summary
| ### Nested classes ||
|----------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` class` | [PrecomputedText.Params](https://developer.android.com/reference/android/text/PrecomputedText.Params) The information required for building[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText). |
| ### Inherited constants |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| From interface[android.text.Spanned](https://developer.android.com/reference/android/text/Spanned) |-------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | `int` | [SPAN_COMPOSING](https://developer.android.com/reference/android/text/Spanned#SPAN_COMPOSING) This flag is set on spans that are being used to apply temporary styling information on the composing text of an input method, so that they can be found and removed when the composing text is being replaced. | | `int` | [SPAN_EXCLUSIVE_EXCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_EXCLUSIVE_EXCLUSIVE) Spans of type SPAN_EXCLUSIVE_EXCLUSIVE do not expand to include text inserted at either their starting or ending point. | | `int` | [SPAN_EXCLUSIVE_INCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_EXCLUSIVE_INCLUSIVE) Non-0-length spans of type SPAN_EXCLUSIVE_INCLUSIVE expand to include text inserted at their ending point but not at their starting point. | | `int` | [SPAN_INCLUSIVE_EXCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_INCLUSIVE_EXCLUSIVE) Non-0-length spans of type SPAN_INCLUSIVE_EXCLUSIVE expand to include text inserted at their starting point but not at their ending point. | | `int` | [SPAN_INCLUSIVE_INCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_INCLUSIVE_INCLUSIVE) Spans of type SPAN_INCLUSIVE_INCLUSIVE expand to include text inserted at either their starting or ending point. | | `int` | [SPAN_INTERMEDIATE](https://developer.android.com/reference/android/text/Spanned#SPAN_INTERMEDIATE) This flag will be set for intermediate span changes, meaning there is guaranteed to be another change following it. | | `int` | [SPAN_MARK_MARK](https://developer.android.com/reference/android/text/Spanned#SPAN_MARK_MARK) 0-length spans with type SPAN_MARK_MARK behave like text marks: they remain at their original offset when text is inserted at that offset. | | `int` | [SPAN_MARK_POINT](https://developer.android.com/reference/android/text/Spanned#SPAN_MARK_POINT) SPAN_MARK_POINT is a synonym for[SPAN_INCLUSIVE_INCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_INCLUSIVE_INCLUSIVE). | | `int` | [SPAN_PARAGRAPH](https://developer.android.com/reference/android/text/Spanned#SPAN_PARAGRAPH) SPAN_PARAGRAPH behaves like SPAN_INCLUSIVE_EXCLUSIVE (SPAN_MARK_MARK), except that if either end of the span is at the end of the buffer, that end behaves like _POINT instead (so SPAN_INCLUSIVE_INCLUSIVE if it starts in the middle and ends at the end, or SPAN_EXCLUSIVE_INCLUSIVE if it both starts and ends at the end). | | `int` | [SPAN_POINT_MARK](https://developer.android.com/reference/android/text/Spanned#SPAN_POINT_MARK) SPAN_POINT_MARK is a synonym for[SPAN_EXCLUSIVE_EXCLUSIVE](https://developer.android.com/reference/android/text/Spanned#SPAN_EXCLUSIVE_EXCLUSIVE). | | `int` | [SPAN_POINT_MARK_MASK](https://developer.android.com/reference/android/text/Spanned#SPAN_POINT_MARK_MASK) Bitmask of bits that are relevent for controlling point/mark behavior of spans. | | `int` | [SPAN_POINT_POINT](https://developer.android.com/reference/android/text/Spanned#SPAN_POINT_POINT) 0-length spans with type SPAN_POINT_POINT behave like cursors: they are pushed forward by the length of the insertion when text is inserted at their offset. | | `int` | [SPAN_PRIORITY](https://developer.android.com/reference/android/text/Spanned#SPAN_PRIORITY) The bits specified by the SPAN_PRIORITY bitmap determine the order of change notifications -- higher numbers go first. | | `int` | [SPAN_PRIORITY_SHIFT](https://developer.android.com/reference/android/text/Spanned#SPAN_PRIORITY_SHIFT) The bits numbered just above SPAN_PRIORITY_SHIFT determine the order of change notifications -- higher numbers go first. | | `int` | [SPAN_USER](https://developer.android.com/reference/android/text/Spanned#SPAN_USER) The bits specified by the SPAN_USER bitfield are available for callers to use to store scalar data associated with their span object. | | `int` | [SPAN_USER_SHIFT](https://developer.android.com/reference/android/text/Spanned#SPAN_USER_SHIFT) The bits numbered SPAN_USER_SHIFT and above are available for callers to use to store scalar data associated with their span object. | |
| ### Public methods ||
|----------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` char` | ` `[charAt](https://developer.android.com/reference/android/text/PrecomputedText#charAt(int))`(int index) ` Returns the`char`value at the specified index. |
| ` static `[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText) | ` `[create](https://developer.android.com/reference/android/text/PrecomputedText#create(java.lang.CharSequence,%20android.text.PrecomputedText.Params))`(`[CharSequence](https://developer.android.com/reference/java/lang/CharSequence)` text, `[PrecomputedText.Params](https://developer.android.com/reference/android/text/PrecomputedText.Params)` params) ` Create a new[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText)which will pre-compute text measurement and glyph positioning information. |
| ` void` | ` `[getBounds](https://developer.android.com/reference/android/text/PrecomputedText#getBounds(int,%20int,%20android.graphics.Rect))`(int start, int end, `[Rect](https://developer.android.com/reference/android/graphics/Rect)` bounds) ` Retrieves the text bounding box for the given range. |
| ` void` | ` `[getFontMetricsInt](https://developer.android.com/reference/android/text/PrecomputedText#getFontMetricsInt(int,%20int,%20android.graphics.Paint.FontMetricsInt))`(int start, int end, `[Paint.FontMetricsInt](https://developer.android.com/reference/android/graphics/Paint.FontMetricsInt)` outMetrics) ` Retrieves the text font metrics for the given range. |
| ` int` | ` `[getParagraphCount](https://developer.android.com/reference/android/text/PrecomputedText#getParagraphCount())`() ` Returns the count of paragraphs. |
| ` int` | ` `[getParagraphEnd](https://developer.android.com/reference/android/text/PrecomputedText#getParagraphEnd(int))`(int paraIndex) ` Returns the paragraph end offset of the text. |
| ` int` | ` `[getParagraphStart](https://developer.android.com/reference/android/text/PrecomputedText#getParagraphStart(int))`(int paraIndex) ` Returns the paragraph start offset of the text. |
| ` `[PrecomputedText.Params](https://developer.android.com/reference/android/text/PrecomputedText.Params) | ` `[getParams](https://developer.android.com/reference/android/text/PrecomputedText#getParams())`() ` Returns the layout parameters used to measure this text. |
| ` int` | ` `[getSpanEnd](https://developer.android.com/reference/android/text/PrecomputedText#getSpanEnd(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` 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](https://developer.android.com/reference/android/text/PrecomputedText#getSpanFlags(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` Return the flags that were specified when[Spannable.setSpan](https://developer.android.com/reference/android/text/Spannable#setSpan(java.lang.Object,%20int,%20int,%20int))was used to attach the specified markup object, or 0 if the specified object has not been attached. |
| ` int` | ` `[getSpanStart](https://developer.android.com/reference/android/text/PrecomputedText#getSpanStart(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` 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[]` | ` `[getSpans](https://developer.android.com/reference/android/text/PrecomputedText#getSpans(int,%20int,%20java.lang.Class))`(int start, int end, `[Class](https://developer.android.com/reference/java/lang/Class)` type) ` 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. |
| ` float` | ` `[getWidth](https://developer.android.com/reference/android/text/PrecomputedText#getWidth(int,%20int))`(int start, int end) ` Returns text width for the given range. |
| ` int` | ` `[length](https://developer.android.com/reference/android/text/PrecomputedText#length())`() ` Returns the length of this character sequence. |
| ` int` | ` `[nextSpanTransition](https://developer.android.com/reference/android/text/PrecomputedText#nextSpanTransition(int,%20int,%20java.lang.Class))`(int start, int limit, `[Class](https://developer.android.com/reference/java/lang/Class)` type) ` 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`. |
| ` void` | ` `[removeSpan](https://developer.android.com/reference/android/text/PrecomputedText#removeSpan(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` what) ` Remove the specified object from the range of text to which it was attached, if any. |
| ` void` | ` `[setSpan](https://developer.android.com/reference/android/text/PrecomputedText#setSpan(java.lang.Object,%20int,%20int,%20int))`(`[Object](https://developer.android.com/reference/java/lang/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. |
| ` `[CharSequence](https://developer.android.com/reference/java/lang/CharSequence) | ` `[subSequence](https://developer.android.com/reference/android/text/PrecomputedText#subSequence(int,%20int))`(int start, int end) ` Returns a`CharSequence`that is a subsequence of this sequence. |
| ` `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/android/text/PrecomputedText#toString())`() ` Returns a string representation of the object. |
| ### Inherited methods |
|-----------------------|---|
| From class` `[java.lang.Object](https://developer.android.com/reference/java/lang/Object)` ` |--------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` `[Object](https://developer.android.com/reference/java/lang/Object) | ` `[clone](https://developer.android.com/reference/java/lang/Object#clone())`() ` Creates and returns a copy of this object. | | ` boolean` | ` `[equals](https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` `[finalize](https://developer.android.com/reference/java/lang/Object#finalize())`() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | | ` final `[Class](https://developer.android.com/reference/java/lang/Class)`` | ` `[getClass](https://developer.android.com/reference/java/lang/Object#getClass())`() ` Returns the runtime class of this`Object`. | | ` int` | ` `[hashCode](https://developer.android.com/reference/java/lang/Object#hashCode())`() ` Returns a hash code value for the object. | | ` final void` | ` `[notify](https://developer.android.com/reference/java/lang/Object#notify())`() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` `[notifyAll](https://developer.android.com/reference/java/lang/Object#notifyAll())`() ` Wakes up all threads that are waiting on this object's monitor. | | ` `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/java/lang/Object#toString())`() ` Returns a string representation of the object. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long,%20int))`(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long))`(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait())`() ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*. | ||
| From interface` `[android.text.Spannable](https://developer.android.com/reference/android/text/Spannable)` ` |------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract void` | ` `[removeSpan](https://developer.android.com/reference/android/text/Spannable#removeSpan(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` what) ` Remove the specified object from the range of text to which it was attached, if any. | | ` abstract void` | ` `[setSpan](https://developer.android.com/reference/android/text/Spannable#setSpan(java.lang.Object,%20int,%20int,%20int))`(`[Object](https://developer.android.com/reference/java/lang/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. | ||
| From interface` `[android.text.Spanned](https://developer.android.com/reference/android/text/Spanned)` ` |---------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract int` | ` `[getSpanEnd](https://developer.android.com/reference/android/text/Spanned#getSpanEnd(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` Return the end of the range of text to which the specified markup object is attached, or -1 if the object is not attached. | | ` abstract int` | ` `[getSpanFlags](https://developer.android.com/reference/android/text/Spanned#getSpanFlags(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` Return the flags that were specified when[Spannable.setSpan](https://developer.android.com/reference/android/text/Spannable#setSpan(java.lang.Object,%20int,%20int,%20int))was used to attach the specified markup object, or 0 if the specified object has not been attached. | | ` abstract int` | ` `[getSpanStart](https://developer.android.com/reference/android/text/Spanned#getSpanStart(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` tag) ` Return the beginning of the range of text to which the specified markup object is attached, or -1 if the object is not attached. | | ` abstract T[]` | ` `[getSpans](https://developer.android.com/reference/android/text/Spanned#getSpans(int,%20int,%20java.lang.Class))`(int start, int end, `[Class](https://developer.android.com/reference/java/lang/Class)` type) ` 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. | | ` abstract int` | ` `[nextSpanTransition](https://developer.android.com/reference/android/text/Spanned#nextSpanTransition(int,%20int,%20java.lang.Class))`(int start, int limit, `[Class](https://developer.android.com/reference/java/lang/Class)` type) ` 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`. | ||
| From interface` `[java.lang.CharSequence](https://developer.android.com/reference/java/lang/CharSequence)` ` |--------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract char` | ` `[charAt](https://developer.android.com/reference/java/lang/CharSequence#charAt(int))`(int index) ` Returns the`char`value at the specified index. | | ` default `[IntStream](https://developer.android.com/reference/java/util/stream/IntStream) | ` `[chars](https://developer.android.com/reference/java/lang/CharSequence#chars())`() ` Returns a stream of`int`zero-extending the`char`values from this sequence. | | ` default `[IntStream](https://developer.android.com/reference/java/util/stream/IntStream) | ` `[codePoints](https://developer.android.com/reference/java/lang/CharSequence#codePoints())`() ` Returns a stream of code point values from this sequence. | | ` static int` | ` `[compare](https://developer.android.com/reference/java/lang/CharSequence#compare(java.lang.CharSequence,%20java.lang.CharSequence))`(`[CharSequence](https://developer.android.com/reference/java/lang/CharSequence)` cs1, `[CharSequence](https://developer.android.com/reference/java/lang/CharSequence)` cs2) ` Compares two`CharSequence`instances lexicographically. | | ` default boolean` | ` `[isEmpty](https://developer.android.com/reference/java/lang/CharSequence#isEmpty())`() ` Returns`true`if this character sequence is empty. | | ` abstract int` | ` `[length](https://developer.android.com/reference/java/lang/CharSequence#length())`() ` Returns the length of this character sequence. | | ` abstract `[CharSequence](https://developer.android.com/reference/java/lang/CharSequence) | ` `[subSequence](https://developer.android.com/reference/java/lang/CharSequence#subSequence(int,%20int))`(int start, int end) ` Returns a`CharSequence`that is a subsequence of this sequence. | | ` abstract `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/java/lang/CharSequence#toString())`() ` Returns a string containing the characters in this sequence in the same order as this sequence. | ||
## Public methods
### charAt
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public char charAt (int index)
```
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](https://reference/java/lang/Character.html#unicode), the surrogate value is returned.
| Parameters ||
|---------|----------------------------------------------------------|
| `index` | `int`: the index of the`char`value to be returned
|
| Returns ||
|--------|---------------------------------|
| `char` | the specified`char`value
|
### create
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public static PrecomputedText create (CharSequence text,
PrecomputedText.Params params)
```
Create a new[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText)which will pre-compute text measurement and glyph positioning information.
This can be expensive, so computing this on a background thread before your text will be presented can save work on the UI thread.
Note that any[NoCopySpan](https://developer.android.com/reference/android/text/NoCopySpan)attached to the text won't be passed to the created PrecomputedText.
| Parameters ||
|----------|------------------------------------------------------------------------------------------------------------------|
| `text` | `CharSequence`: the text to be measured This value cannot be`null`.
|
| `params` | `PrecomputedText.Params`: parameters that define how text will be precomputed This value cannot be`null`.
|
| Returns ||
|-----------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------|
| [PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText) | A[PrecomputedText](https://developer.android.com/reference/android/text/PrecomputedText)
|
### getBounds
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void getBounds (int start,
int end,
Rect bounds)
```
Retrieves the text bounding box for the given range. Both`start`and`end`offset need to be in the same paragraph, otherwise IllegalArgumentException will be thrown.
| Parameters ||
|----------|----------------------------------------------------------------------------|
| `start` | `int`: the inclusive start offset in the text Value is 0 or greater
|
| `end` | `int`: the exclusive end offset in the text Value is 0 or greater
|
| `bounds` | `Rect`: the output rectangle This value cannot be`null`.
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|---------------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | if start and end offset are in the different paragraph. |
### getFontMetricsInt
Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void getFontMetricsInt (int start,
int end,
Paint.FontMetricsInt outMetrics)
```
Retrieves the text font metrics for the given range. Both`start`and`end`offset need to be in the same paragraph, otherwise IllegalArgumentException will be thrown.
| Parameters ||
|--------------|------------------------------------------------------------------------------------|
| `start` | `int`: the inclusive start offset in the text Value is 0 or greater
|
| `end` | `int`: the exclusive end offset in the text Value is 0 or greater
|
| `outMetrics` | `Paint.FontMetricsInt`: the output font metrics This value cannot be`null`.
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|---------------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | if start and end offset are in the different paragraph. |
### getParagraphCount
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getParagraphCount ()
```
Returns the count of paragraphs.
| Returns ||
|-------|------------------------------|
| `int` | Value is 0 or greater
|
### getParagraphEnd
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getParagraphEnd (int paraIndex)
```
Returns the paragraph end offset of the text.
| Parameters ||
|-------------|-------------------------------------|
| `paraIndex` | `int`: Value is 0 or greater
|
| Returns ||
|-------|------------------------------|
| `int` | Value is 0 or greater
|
### getParagraphStart
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getParagraphStart (int paraIndex)
```
Returns the paragraph start offset of the text.
| Parameters ||
|-------------|-------------------------------------|
| `paraIndex` | `int`: Value is 0 or greater
|
| Returns ||
|-------|------------------------------|
| `int` | Value is 0 or greater
|
### getParams
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public PrecomputedText.Params getParams ()
```
Returns the layout parameters used to measure this text.
| Returns ||
|-------------------------------------------------------------------------------------------------------|------------------------------------|
| [PrecomputedText.Params](https://developer.android.com/reference/android/text/PrecomputedText.Params) | This value cannot be`null`.
|
### getSpanEnd
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getSpanEnd (Object tag)
```
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 ||
|-------|-----------------|
| `tag` | `Object`
|
| Returns ||
|-------|--------|
| `int` |
|
### getSpanFlags
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getSpanFlags (Object tag)
```
Return the flags that were specified when[Spannable.setSpan](https://developer.android.com/reference/android/text/Spannable#setSpan(java.lang.Object,%20int,%20int,%20int))was used to attach the specified markup object, or 0 if the specified object has not been attached.
| Parameters ||
|-------|-----------------|
| `tag` | `Object`
|
| Returns ||
|-------|--------|
| `int` |
|
### getSpanStart
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int getSpanStart (Object tag)
```
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 ||
|-------|-----------------|
| `tag` | `Object`
|
| Returns ||
|-------|--------|
| `int` |
|
### getSpans
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public T[] getSpans (int start,
int end,
Class type)
```
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 ||
|---------|----------------|
| `start` | `int`
|
| `end` | `int`
|
| `type` | `Class`
|
| Returns ||
|-------|--------|
| `T[]` |
|
### getWidth
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public float getWidth (int start,
int end)
```
Returns text width for the given range. Both`start`and`end`offset need to be in the same paragraph, otherwise IllegalArgumentException will be thrown.
| Parameters ||
|---------|----------------------------------------------------------------------------|
| `start` | `int`: the inclusive start offset in the text Value is 0 or greater
|
| `end` | `int`: the exclusive end offset in the text Value is 0 or greater
|
| Returns ||
|---------|------------------------------------------------|
| `float` | the text width Value is 0.0f or greater
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|---------------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | if start and end offset are in the different paragraph. |
### length
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int length ()
```
Returns the length of this character sequence. The length is the number of 16-bit`char`s in the sequence.
| Returns ||
|-------|----------------------------------------------|
| `int` | the number of`char`s in this sequence
|
### nextSpanTransition
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int nextSpanTransition (int start,
int limit,
Class type)
```
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 ||
|---------|----------------|
| `start` | `int`
|
| `limit` | `int`
|
| `type` | `Class`
|
| Returns ||
|-------|--------|
| `int` |
|
### removeSpan
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
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 ||
|--------|-----------------|
| `what` | `Object`
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | if[MetricAffectingSpan](https://developer.android.com/reference/android/text/style/MetricAffectingSpan)is specified. |
### setSpan
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
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](https://developer.android.com/reference/android/text/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](https://developer.android.com/reference/android/text/style/CharacterStyle)and[ParagraphStyle](https://developer.android.com/reference/android/text/style/ParagraphStyle), and[TextWatcher](https://developer.android.com/reference/android/text/TextWatcher)and[SpanWatcher](https://developer.android.com/reference/android/text/SpanWatcher).
| Parameters ||
|---------|-----------------|
| `what` | `Object`
|
| `start` | `int`
|
| `end` | `int`
|
| `flags` | `int`
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | if[MetricAffectingSpan](https://developer.android.com/reference/android/text/style/MetricAffectingSpan)is specified. |
### subSequence
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public 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 ||
|---------|------------------------------------------|
| `start` | `int`: the start index, inclusive
|
| `end` | `int`: the end index, exclusive
|
| Returns ||
|--------------------------------------------------------------------------------|----------------------------------|
| [CharSequence](https://developer.android.com/reference/java/lang/CharSequence) | the specified subsequence
|
### toString
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public String toString ()
```
Returns a string representation of the object.
| Returns ||
|--------------------------------------------------------------------|-----------------------------------------------|
| [String](https://developer.android.com/reference/java/lang/String) | a string representation of the object.
|