Merge "Introduce OffsetMapping for TextView TransformationMethod" (8793d67a) · Commits · e / os / android_frameworks_base

core/java/android/text/DynamicLayout.java

+45 −6

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@ import android.compat.annotation.UnsupportedAppUsage;
		import android.graphics.Paint;
		import android.graphics.Rect;
		import android.os.Build;
		import android.text.method.OffsetMapping;
		import android.text.style.ReplacementSpan;
		import android.text.style.UpdateLayout;
		import android.text.style.WrapTogetherSpan;
		@@ -1095,10 +1096,27 @@ public class DynamicLayout extends Layout {
		}

		public void beforeTextChanged(CharSequence s, int where, int before, int after) {
		// Intentionally empty
		final DynamicLayout dynamicLayout = mLayout.get();
		if (dynamicLayout != null && dynamicLayout.mDisplay instanceof OffsetMapping) {
		final OffsetMapping transformedText = (OffsetMapping) dynamicLayout.mDisplay;
		if (mTransformedTextUpdate == null) {
		mTransformedTextUpdate = new OffsetMapping.TextUpdate(where, before, after);
		} else {
		mTransformedTextUpdate.where = where;
		mTransformedTextUpdate.before = before;
		mTransformedTextUpdate.after = after;
		}
		transformedText.originalToTransformed(mTransformedTextUpdate);
		}
		}

		public void onTextChanged(CharSequence s, int where, int before, int after) {
		final DynamicLayout dynamicLayout = mLayout.get();
		if (dynamicLayout != null && dynamicLayout.mDisplay instanceof OffsetMapping) {
		where = mTransformedTextUpdate.where;
		before = mTransformedTextUpdate.before;
		after = mTransformedTextUpdate.after;
		}
		reflow(s, where, before, after);
		}

		@@ -1106,14 +1124,34 @@ public class DynamicLayout extends Layout {
		// Intentionally empty
		}

		public void onSpanAdded(Spannable s, Object o, int start, int end) {
		if (o instanceof UpdateLayout)
		/**
		* Reflow the {@link DynamicLayout} at the given range from {@code start} to the
		* {@code end}.
		* If the display text in this {@link DynamicLayout} is a {@link OffsetMapping} instance
		* (which means it's also a transformed text), it will transform the given range first and
		* then reflow.
		*/
		private void transformAndReflow(Spannable s, int start, int end) {
		final DynamicLayout dynamicLayout = mLayout.get();
		if (dynamicLayout != null && dynamicLayout.mDisplay instanceof OffsetMapping) {
		final OffsetMapping transformedText = (OffsetMapping) dynamicLayout.mDisplay;
		start = transformedText.originalToTransformed(start,
		OffsetMapping.MAP_STRATEGY_CHARACTER);
		end = transformedText.originalToTransformed(end,
		OffsetMapping.MAP_STRATEGY_CHARACTER);
		}
		reflow(s, start, end - start, end - start);
		}

		public void onSpanAdded(Spannable s, Object o, int start, int end) {
		if (o instanceof UpdateLayout) {
		transformAndReflow(s, start, end);
		}
		}

		public void onSpanRemoved(Spannable s, Object o, int start, int end) {
		if (o instanceof UpdateLayout)
		reflow(s, start, end - start, end - start);
		transformAndReflow(s, start, end);
		}

		public void onSpanChanged(Spannable s, Object o, int start, int end, int nstart, int nend) {
		@@ -1123,12 +1161,13 @@ public class DynamicLayout extends Layout {
		// instead of causing an exception
		start = 0;
		}
		reflow(s, start, end - start, end - start);
		reflow(s, nstart, nend - nstart, nend - nstart);
		transformAndReflow(s, start, end);
		transformAndReflow(s, nstart, nend);
		}
		}

		private WeakReference<DynamicLayout> mLayout;
		private OffsetMapping.TextUpdate mTransformedTextUpdate;
		}

		@Override

core/java/android/text/method/ArrowKeyMovementMethod.java

+30 −0

Original line number	Diff line number	Diff line
		@@ -68,6 +68,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean left(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendLeft(buffer, layout);
		@@ -78,6 +81,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean right(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendRight(buffer, layout);
		@@ -88,6 +94,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean up(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendUp(buffer, layout);
		@@ -98,6 +107,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean down(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendDown(buffer, layout);
		@@ -108,6 +120,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean pageUp(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		final boolean selecting = isSelecting(buffer);
		final int targetY = getCurrentLineTop(buffer, layout) - getPageHeight(widget);
		@@ -132,6 +147,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean pageDown(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		final boolean selecting = isSelecting(buffer);
		final int targetY = getCurrentLineTop(buffer, layout) + getPageHeight(widget);
		@@ -176,6 +194,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean lineStart(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendToLeftEdge(buffer, layout);
		@@ -186,6 +207,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		protected boolean lineEnd(TextView widget, Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendToRightEdge(buffer, layout);
		@@ -224,6 +248,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		public boolean previousParagraph(@NonNull TextView widget, @NonNull Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendToParagraphStart(buffer);
		@@ -234,6 +261,9 @@ public class ArrowKeyMovementMethod extends BaseMovementMethod implements Moveme

		@Override
		public boolean nextParagraph(@NonNull TextView widget, @NonNull Spannable buffer) {
		if (widget.isOffsetMappingAvailable()) {
		return false;
		}
		final Layout layout = widget.getLayout();
		if (isSelecting(buffer)) {
		return Selection.extendToParagraphEnd(buffer);

core/java/android/text/method/BaseKeyListener.java

+3 −2

Original line number	Diff line number	Diff line
		@@ -440,8 +440,9 @@ public abstract class BaseKeyListener extends MetaKeyKeyListener

		private boolean deleteLine(View view, Editable content) {
		if (view instanceof TextView) {
		final Layout layout = ((TextView) view).getLayout();
		if (layout != null) {
		final TextView textView = (TextView) view;
		final Layout layout = textView.getLayout();
		if (layout != null && !textView.isOffsetMappingAvailable()) {
		final int line = layout.getLineForOffset(Selection.getSelectionStart(content));
		final int start = layout.getLineStart(line);
		final int end = layout.getLineEnd(line);

core/java/android/text/method/LinkMovementMethod.java

+4 −0

Original line number	Diff line number	Diff line
		@@ -100,6 +100,10 @@ public class LinkMovementMethod extends ScrollingMovementMethod {

		private boolean action(int what, TextView widget, Spannable buffer) {
		Layout layout = widget.getLayout();
		if (widget.isOffsetMappingAvailable()) {
		// The text in the layout is transformed and has OffsetMapping, don't do anything.
		return false;
		}

		int padding = widget.getTotalPaddingTop() +
		widget.getTotalPaddingBottom();

core/java/android/text/method/OffsetMapping.java

0 → 100644

+170 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2022 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package android.text.method;

		import android.annotation.IntDef;

		import java.lang.annotation.Retention;
		import java.lang.annotation.RetentionPolicy;

		/**
		* The interface for the index mapping information of a transformed text returned by
		* {@link TransformationMethod}. This class is mainly used to support the
		* {@link TransformationMethod} that alters the text length.
		* @hide
		*/
		public interface OffsetMapping {
		/**
		* The mapping strategy for a character offset.
		*
		* @see #originalToTransformed(int, int)
		* @see #transformedToOriginal(int, int)
		*/
		int MAP_STRATEGY_CHARACTER = 0;

		/**
		* The mapping strategy for a cursor position.
		*
		* @see #originalToTransformed(int, int)
		* @see #transformedToOriginal(int, int)
		*/
		int MAP_STRATEGY_CURSOR = 1;

		@IntDef(prefix = { "MAP_STRATEGY" }, value = {
		MAP_STRATEGY_CHARACTER,
		MAP_STRATEGY_CURSOR
		})
		@Retention(RetentionPolicy.SOURCE)
		@interface MapStrategy {}

		/**
		* Map an offset at original text to the offset at transformed text. <br/>
		*
		* This function must be a monotonically non-decreasing function. In other words, if the offset
		* advances at the original text, the offset at the transformed text must advance or stay there.
		* <br/>
		*
		* Depending on the mapping strategy, a same offset can be mapped differently. For example,
		* <pre>
		* Original: ABCDE
		* Transformed: ABCXDE ('X' is introduced due to the transformation.)
		* </pre>
		* Let's check the offset 3, which is the offset of the character 'D'.
		* If we want to map the character offset 3, it should be mapped to index 4.
		* If we want to map the cursor offset 3 (the offset of the character before which the cursor is
		* placed), it's unclear if the mapped cursor is before 'X' or after 'X'.
		* This depends on how the transformed text reacts an insertion at offset 3 in the original
		* text. Assume character 'V' is insert at offset 3 in the original text, and the original text
		* become "ABCVDE". The transformed text can be:
		* <pre>
		* 1) "ABCVXDE"
		* or
		* 2) "ABCXVDE"
		* </pre>
		* In the first case, the offset 3 should be mapped to 3 (before 'X'). And in the second case,
		* the offset should be mapped to 4 (after 'X').<br/>
		*
		* In some cases, a character offset at the original text doesn't have a proper corresponding
		* offset at the transformed text. For example:
		* <pre>
		* Original: ABCDE
		* Transformed: ABDE ('C' is deleted due to the transformation.)
		* </pre>
		* The character offset 2 can be mapped either to offset 2 or 3, but neither is meaningful. For
		* convenience, it MUST map to the next offset (offset 3 in this case), or the
		* transformedText.length() if there is no valid character to map.
		* This is mandatory when the map strategy is {@link #MAP_STRATEGY_CHARACTER}, but doesn't
		* apply for other map strategies.
		*
		* @param offset the offset at the original text. It's normally equal to or less than the
		* originalText.length(). When {@link #MAP_STRATEGY_CHARACTER} is passed, it must
		* be less than originalText.length(). For convenience, it's also allowed to be
		* negative, which represents an invalid offset. When the given offset is
		* negative, this method should return it as it is.
		* @param strategy the mapping strategy. Depending on its value, the same offset can be mapped
		* differently.
		* @return the mapped offset at the transformed text, must be equal to or less than the
		* transformedText.length().
		*
		* @see #transformedToOriginal(int, int)
		*/
		int originalToTransformed(int offset, @MapStrategy int strategy);

		/**
		* Map an offset at transformed text to the offset at original text. This is the reverse method
		* of {@link #originalToTransformed(int, int)}. <br/>
		* This function must be a monotonically non-decreasing function. In other words, if the offset
		* advances at the original text, the offset at the transformed text must advance or stay there.
		* <br/>
		* Similar to the {@link #originalToTransformed(int, int)} if a character offset doesn't have a
		* corresponding offset at the transformed text, it MUST return the value as the previous
		* offset. This is mandatory when the map strategy is {@link #MAP_STRATEGY_CHARACTER},
		* but doesn't apply for other map strategies.
		*
		* @param offset the offset at the transformed text. It's normally equal to or less than the
		* transformedText.length(). When {@link #MAP_STRATEGY_CHARACTER} is passed, it
		* must be less than transformedText.length(). For convenience, it's also allowed
		* to be negative, which represents an invalid offset. When the given offset is
		* negative, this method should return it as it is.
		* @param strategy the mapping strategy. Depending on its value, the same offset can be mapped
		* differently.
		* @return the mapped offset at the original text, must be equal to or less than the
		* original.length().
		*
		* @see #originalToTransformed(int, int)
		*/
		int transformedToOriginal(int offset, @MapStrategy int strategy);

		/**
		* Map a text update in the original text to an update the transformed text.
		* This method used to determine how the transformed text is updated in response to an
		* update in the original text. It is always called before the original text being changed.
		*
		* The main usage of this method is to update text layout incrementally. So it should report
		* the range where text needs to be laid out again.
		*
		* @param textUpdate the {@link TextUpdate} object containing the text update information on
		* the original text. The transformed text update information will also be
		* stored at this object.
		*/
		void originalToTransformed(TextUpdate textUpdate);

		/**
		* The class that stores the text update information that from index <code>where</code>,
		* <code>after</code> characters will replace the old text that has length <code>before</code>.
		*/
		class TextUpdate {
		/** The start index of the text update range, inclusive */
		public int where;
		/** The length of the replaced old text. */
		public int before;
		/** The length of the new text that replaces the old text. */
		public int after;

		/**
		* Creates a {@link TextUpdate} object.
		* @param where the start index of the text update range.
		* @param before the length of the replaced old text.
		* @param after the length of the new text that replaces the old text.
		*/
		public TextUpdate(int where, int before, int after) {
		this.where = where;
		this.before = before;
		this.after = after;
		}
		}
		}