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open class PrecomputedTextCompat : Spannable
   ↳ androidx.core.text.PrecomputedTextCompat

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 PrecomputedTextCompat is created with a given CharSequence, it will measure the text metrics during the creation. This PrecomputedText instance can be set on android.widget.TextView or StaticLayout. Since the text layout information will be included in this instance, android.widget.TextView or StaticLayout will not have to recalculate this information. On API 29 or later, there is full PrecomputedText support by framework. From API 21 to API 27, PrecomputedTextCompat relies on internal text layout cache. PrecomputedTextCompat immediately computes the text layout in the constuctor to warm up the internal text layout cache. On API 20 or before, PrecomputedTextCompat does nothing. Note that any android.text.NoCopySpan attached to the original text won't be passed to PrecomputedText.


Nested classes

The information required for building PrecomputedTextCompat.

Public methods
open static PrecomputedTextCompat!
create(@NonNull text: CharSequence, @NonNull params: PrecomputedTextCompat.Params)

Create a new PrecomputedText which will pre-compute text measurement and glyph positioning information.

open Char
get(index: Int)

open Int

Returns the count of paragraphs.

open Int
getParagraphEnd(@IntRange(0) paraIndex: Int)

Returns the paragraph end offset of the text.

open Int
getParagraphStart(@IntRange(0) paraIndex: Int)

Returns the paragraph start offset of the text.

open PrecomputedTextCompat.Params

Returns the parameters used to measure this text.

open Int
getSpanEnd(tag: Any!)

open Int

open Int

open Array<T>!
getSpans(start: Int, end: Int, type: Class<T>!)

open static Future<PrecomputedTextCompat!>!
getTextFuture(@NonNull charSequence: CharSequence, @NonNull params: PrecomputedTextCompat.Params, @Nullable executor: Executor?)

Helper for PrecomputedText that returns a future to be used with androidx.appcompat.widget.AppCompatTextView#setTextFuture.

open Int
nextSpanTransition(start: Int, limit: Int, type: Class<Any!>!)

open Unit
removeSpan(what: Any!)

open Unit
setSpan(what: Any!, start: Int, end: Int, flags: Int)

open CharSequence
subSequence(startIndex: Int, endIndex: Int)

open String

open Int

Public methods


open static fun create(
    @NonNull text: CharSequence,
    @NonNull params: PrecomputedTextCompat.Params
): PrecomputedTextCompat!

Create a new 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 android.text.NoCopySpan attached to the text won't be passed to the created PrecomputedText.