| /* |
| * Copyright (C) 2010 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; |
| |
| import android.annotation.IntRange; |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.compat.annotation.UnsupportedAppUsage; |
| import android.graphics.Canvas; |
| import android.graphics.Paint; |
| import android.graphics.Paint.FontMetricsInt; |
| import android.os.Build; |
| import android.text.Layout.Directions; |
| import android.text.Layout.TabStops; |
| import android.text.style.CharacterStyle; |
| import android.text.style.MetricAffectingSpan; |
| import android.text.style.ReplacementSpan; |
| import android.util.Log; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.ArrayUtils; |
| |
| import java.util.ArrayList; |
| |
| /** |
| * Represents a line of styled text, for measuring in visual order and |
| * for rendering. |
| * |
| * <p>Get a new instance using obtain(), and when finished with it, return it |
| * to the pool using recycle(). |
| * |
| * <p>Call set to prepare the instance for use, then either draw, measure, |
| * metrics, or caretToLeftRightOf. |
| * |
| * @hide |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| public class TextLine { |
| private static final boolean DEBUG = false; |
| |
| private static final char TAB_CHAR = '\t'; |
| |
| private TextPaint mPaint; |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| private CharSequence mText; |
| private int mStart; |
| private int mLen; |
| private int mDir; |
| private Directions mDirections; |
| private boolean mHasTabs; |
| private TabStops mTabs; |
| private char[] mChars; |
| private boolean mCharsValid; |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) |
| private Spanned mSpanned; |
| private PrecomputedText mComputed; |
| |
| // The start and end of a potentially existing ellipsis on this text line. |
| // We use them to filter out replacement and metric affecting spans on ellipsized away chars. |
| private int mEllipsisStart; |
| private int mEllipsisEnd; |
| |
| // Additional width of whitespace for justification. This value is per whitespace, thus |
| // the line width will increase by mAddedWidthForJustify x (number of stretchable whitespaces). |
| private float mAddedWidthForJustify; |
| private boolean mIsJustifying; |
| |
| private final TextPaint mWorkPaint = new TextPaint(); |
| private final TextPaint mActivePaint = new TextPaint(); |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| private final SpanSet<MetricAffectingSpan> mMetricAffectingSpanSpanSet = |
| new SpanSet<MetricAffectingSpan>(MetricAffectingSpan.class); |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| private final SpanSet<CharacterStyle> mCharacterStyleSpanSet = |
| new SpanSet<CharacterStyle>(CharacterStyle.class); |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) |
| private final SpanSet<ReplacementSpan> mReplacementSpanSpanSet = |
| new SpanSet<ReplacementSpan>(ReplacementSpan.class); |
| |
| private final DecorationInfo mDecorationInfo = new DecorationInfo(); |
| private final ArrayList<DecorationInfo> mDecorations = new ArrayList<>(); |
| |
| /** Not allowed to access. If it's for memory leak workaround, it was already fixed M. */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P) |
| private static final TextLine[] sCached = new TextLine[3]; |
| |
| /** |
| * Returns a new TextLine from the shared pool. |
| * |
| * @return an uninitialized TextLine |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| @UnsupportedAppUsage |
| public static TextLine obtain() { |
| TextLine tl; |
| synchronized (sCached) { |
| for (int i = sCached.length; --i >= 0;) { |
| if (sCached[i] != null) { |
| tl = sCached[i]; |
| sCached[i] = null; |
| return tl; |
| } |
| } |
| } |
| tl = new TextLine(); |
| if (DEBUG) { |
| Log.v("TLINE", "new: " + tl); |
| } |
| return tl; |
| } |
| |
| /** |
| * Puts a TextLine back into the shared pool. Do not use this TextLine once |
| * it has been returned. |
| * @param tl the textLine |
| * @return null, as a convenience from clearing references to the provided |
| * TextLine |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| public static TextLine recycle(TextLine tl) { |
| tl.mText = null; |
| tl.mPaint = null; |
| tl.mDirections = null; |
| tl.mSpanned = null; |
| tl.mTabs = null; |
| tl.mChars = null; |
| tl.mComputed = null; |
| |
| tl.mMetricAffectingSpanSpanSet.recycle(); |
| tl.mCharacterStyleSpanSet.recycle(); |
| tl.mReplacementSpanSpanSet.recycle(); |
| |
| synchronized(sCached) { |
| for (int i = 0; i < sCached.length; ++i) { |
| if (sCached[i] == null) { |
| sCached[i] = tl; |
| break; |
| } |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Initializes a TextLine and prepares it for use. |
| * |
| * @param paint the base paint for the line |
| * @param text the text, can be Styled |
| * @param start the start of the line relative to the text |
| * @param limit the limit of the line relative to the text |
| * @param dir the paragraph direction of this line |
| * @param directions the directions information of this line |
| * @param hasTabs true if the line might contain tabs |
| * @param tabStops the tabStops. Can be null |
| * @param ellipsisStart the start of the ellipsis relative to the line |
| * @param ellipsisEnd the end of the ellipsis relative to the line. When there |
| * is no ellipsis, this should be equal to ellipsisStart. |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| public void set(TextPaint paint, CharSequence text, int start, int limit, int dir, |
| Directions directions, boolean hasTabs, TabStops tabStops, |
| int ellipsisStart, int ellipsisEnd) { |
| mPaint = paint; |
| mText = text; |
| mStart = start; |
| mLen = limit - start; |
| mDir = dir; |
| mDirections = directions; |
| if (mDirections == null) { |
| throw new IllegalArgumentException("Directions cannot be null"); |
| } |
| mHasTabs = hasTabs; |
| mSpanned = null; |
| |
| boolean hasReplacement = false; |
| if (text instanceof Spanned) { |
| mSpanned = (Spanned) text; |
| mReplacementSpanSpanSet.init(mSpanned, start, limit); |
| hasReplacement = mReplacementSpanSpanSet.numberOfSpans > 0; |
| } |
| |
| mComputed = null; |
| if (text instanceof PrecomputedText) { |
| // Here, no need to check line break strategy or hyphenation frequency since there is no |
| // line break concept here. |
| mComputed = (PrecomputedText) text; |
| if (!mComputed.getParams().getTextPaint().equalsForTextMeasurement(paint)) { |
| mComputed = null; |
| } |
| } |
| |
| mCharsValid = hasReplacement; |
| |
| if (mCharsValid) { |
| if (mChars == null || mChars.length < mLen) { |
| mChars = ArrayUtils.newUnpaddedCharArray(mLen); |
| } |
| TextUtils.getChars(text, start, limit, mChars, 0); |
| if (hasReplacement) { |
| // Handle these all at once so we don't have to do it as we go. |
| // Replace the first character of each replacement run with the |
| // object-replacement character and the remainder with zero width |
| // non-break space aka BOM. Cursor movement code skips these |
| // zero-width characters. |
| char[] chars = mChars; |
| for (int i = start, inext; i < limit; i = inext) { |
| inext = mReplacementSpanSpanSet.getNextTransition(i, limit); |
| if (mReplacementSpanSpanSet.hasSpansIntersecting(i, inext) |
| && (i - start >= ellipsisEnd || inext - start <= ellipsisStart)) { |
| // transition into a span |
| chars[i - start] = '\ufffc'; |
| for (int j = i - start + 1, e = inext - start; j < e; ++j) { |
| chars[j] = '\ufeff'; // used as ZWNBS, marks positions to skip |
| } |
| } |
| } |
| } |
| } |
| mTabs = tabStops; |
| mAddedWidthForJustify = 0; |
| mIsJustifying = false; |
| |
| mEllipsisStart = ellipsisStart != ellipsisEnd ? ellipsisStart : 0; |
| mEllipsisEnd = ellipsisStart != ellipsisEnd ? ellipsisEnd : 0; |
| } |
| |
| private char charAt(int i) { |
| return mCharsValid ? mChars[i] : mText.charAt(i + mStart); |
| } |
| |
| /** |
| * Justify the line to the given width. |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| public void justify(float justifyWidth) { |
| int end = mLen; |
| while (end > 0 && isLineEndSpace(mText.charAt(mStart + end - 1))) { |
| end--; |
| } |
| final int spaces = countStretchableSpaces(0, end); |
| if (spaces == 0) { |
| // There are no stretchable spaces, so we can't help the justification by adding any |
| // width. |
| return; |
| } |
| final float width = Math.abs(measure(end, false, null)); |
| mAddedWidthForJustify = (justifyWidth - width) / spaces; |
| mIsJustifying = true; |
| } |
| |
| /** |
| * Renders the TextLine. |
| * |
| * @param c the canvas to render on |
| * @param x the leading margin position |
| * @param top the top of the line |
| * @param y the baseline |
| * @param bottom the bottom of the line |
| */ |
| void draw(Canvas c, float x, int top, int y, int bottom) { |
| float h = 0; |
| final int runCount = mDirections.getRunCount(); |
| for (int runIndex = 0; runIndex < runCount; runIndex++) { |
| final int runStart = mDirections.getRunStart(runIndex); |
| if (runStart > mLen) break; |
| final int runLimit = Math.min(runStart + mDirections.getRunLength(runIndex), mLen); |
| final boolean runIsRtl = mDirections.isRunRtl(runIndex); |
| |
| int segStart = runStart; |
| for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) { |
| if (j == runLimit || charAt(j) == TAB_CHAR) { |
| h += drawRun(c, segStart, j, runIsRtl, x + h, top, y, bottom, |
| runIndex != (runCount - 1) || j != mLen); |
| |
| if (j != runLimit) { // charAt(j) == TAB_CHAR |
| h = mDir * nextTab(h * mDir); |
| } |
| segStart = j + 1; |
| } |
| } |
| } |
| } |
| |
| /** |
| * Returns metrics information for the entire line. |
| * |
| * @param fmi receives font metrics information, can be null |
| * @return the signed width of the line |
| */ |
| @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE) |
| public float metrics(FontMetricsInt fmi) { |
| return measure(mLen, false, fmi); |
| } |
| |
| /** |
| * Returns the signed graphical offset from the leading margin. |
| * |
| * Following examples are all for measuring offset=3. LX(e.g. L0, L1, ...) denotes a |
| * character which has LTR BiDi property. On the other hand, RX(e.g. R0, R1, ...) denotes a |
| * character which has RTL BiDi property. Assuming all character has 1em width. |
| * |
| * Example 1: All LTR chars within LTR context |
| * Input Text (logical) : L0 L1 L2 L3 L4 L5 L6 L7 L8 |
| * Input Text (visual) : L0 L1 L2 L3 L4 L5 L6 L7 L8 |
| * Output(trailing=true) : |--------| (Returns 3em) |
| * Output(trailing=false): |--------| (Returns 3em) |
| * |
| * Example 2: All RTL chars within RTL context. |
| * Input Text (logical) : R0 R1 R2 R3 R4 R5 R6 R7 R8 |
| * Input Text (visual) : R8 R7 R6 R5 R4 R3 R2 R1 R0 |
| * Output(trailing=true) : |--------| (Returns -3em) |
| * Output(trailing=false): |--------| (Returns -3em) |
| * |
| * Example 3: BiDi chars within LTR context. |
| * Input Text (logical) : L0 L1 L2 R3 R4 R5 L6 L7 L8 |
| * Input Text (visual) : L0 L1 L2 R5 R4 R3 L6 L7 L8 |
| * Output(trailing=true) : |-----------------| (Returns 6em) |
| * Output(trailing=false): |--------| (Returns 3em) |
| * |
| * Example 4: BiDi chars within RTL context. |
| * Input Text (logical) : L0 L1 L2 R3 R4 R5 L6 L7 L8 |
| * Input Text (visual) : L6 L7 L8 R5 R4 R3 L0 L1 L2 |
| * Output(trailing=true) : |-----------------| (Returns -6em) |
| * Output(trailing=false): |--------| (Returns -3em) |
| * |
| * @param offset the line-relative character offset, between 0 and the line length, inclusive |
| * @param trailing no effect if the offset is not on the BiDi transition offset. If the offset |
| * is on the BiDi transition offset and true is passed, the offset is regarded |
| * as the edge of the trailing run's edge. If false, the offset is regarded as |
| * the edge of the preceding run's edge. See example above. |
| * @param fmi receives metrics information about the requested character, can be null |
| * @return the signed graphical offset from the leading margin to the requested character edge. |
| * The positive value means the offset is right from the leading edge. The negative |
| * value means the offset is left from the leading edge. |
| */ |
| public float measure(@IntRange(from = 0) int offset, boolean trailing, |
| @NonNull FontMetricsInt fmi) { |
| if (offset > mLen) { |
| throw new IndexOutOfBoundsException( |
| "offset(" + offset + ") should be less than line limit(" + mLen + ")"); |
| } |
| final int target = trailing ? offset - 1 : offset; |
| if (target < 0) { |
| return 0; |
| } |
| |
| float h = 0; |
| for (int runIndex = 0; runIndex < mDirections.getRunCount(); runIndex++) { |
| final int runStart = mDirections.getRunStart(runIndex); |
| if (runStart > mLen) break; |
| final int runLimit = Math.min(runStart + mDirections.getRunLength(runIndex), mLen); |
| final boolean runIsRtl = mDirections.isRunRtl(runIndex); |
| |
| int segStart = runStart; |
| for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) { |
| if (j == runLimit || charAt(j) == TAB_CHAR) { |
| final boolean targetIsInThisSegment = target >= segStart && target < j; |
| final boolean sameDirection = (mDir == Layout.DIR_RIGHT_TO_LEFT) == runIsRtl; |
| |
| if (targetIsInThisSegment && sameDirection) { |
| return h + measureRun(segStart, offset, j, runIsRtl, fmi); |
| } |
| |
| final float segmentWidth = measureRun(segStart, j, j, runIsRtl, fmi); |
| h += sameDirection ? segmentWidth : -segmentWidth; |
| |
| if (targetIsInThisSegment) { |
| return h + measureRun(segStart, offset, j, runIsRtl, null); |
| } |
| |
| if (j != runLimit) { // charAt(j) == TAB_CHAR |
| if (offset == j) { |
| return h; |
| } |
| h = mDir * nextTab(h * mDir); |
| if (target == j) { |
| return h; |
| } |
| } |
| |
| segStart = j + 1; |
| } |
| } |
| } |
| |
| return h; |
| } |
| |
| /** |
| * @see #measure(int, boolean, FontMetricsInt) |
| * @return The measure results for all possible offsets |
| */ |
| @VisibleForTesting |
| public float[] measureAllOffsets(boolean[] trailing, FontMetricsInt fmi) { |
| float[] measurement = new float[mLen + 1]; |
| |
| int[] target = new int[mLen + 1]; |
| for (int offset = 0; offset < target.length; ++offset) { |
| target[offset] = trailing[offset] ? offset - 1 : offset; |
| } |
| if (target[0] < 0) { |
| measurement[0] = 0; |
| } |
| |
| float h = 0; |
| for (int runIndex = 0; runIndex < mDirections.getRunCount(); runIndex++) { |
| final int runStart = mDirections.getRunStart(runIndex); |
| if (runStart > mLen) break; |
| final int runLimit = Math.min(runStart + mDirections.getRunLength(runIndex), mLen); |
| final boolean runIsRtl = mDirections.isRunRtl(runIndex); |
| |
| int segStart = runStart; |
| for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; ++j) { |
| if (j == runLimit || charAt(j) == TAB_CHAR) { |
| final float oldh = h; |
| final boolean advance = (mDir == Layout.DIR_RIGHT_TO_LEFT) == runIsRtl; |
| final float w = measureRun(segStart, j, j, runIsRtl, fmi); |
| h += advance ? w : -w; |
| |
| final float baseh = advance ? oldh : h; |
| FontMetricsInt crtfmi = advance ? fmi : null; |
| for (int offset = segStart; offset <= j && offset <= mLen; ++offset) { |
| if (target[offset] >= segStart && target[offset] < j) { |
| measurement[offset] = |
| baseh + measureRun(segStart, offset, j, runIsRtl, crtfmi); |
| } |
| } |
| |
| if (j != runLimit) { // charAt(j) == TAB_CHAR |
| if (target[j] == j) { |
| measurement[j] = h; |
| } |
| h = mDir * nextTab(h * mDir); |
| if (target[j + 1] == j) { |
| measurement[j + 1] = h; |
| } |
| } |
| |
| segStart = j + 1; |
| } |
| } |
| } |
| if (target[mLen] == mLen) { |
| measurement[mLen] = h; |
| } |
| |
| return measurement; |
| } |
| |
| /** |
| * Draws a unidirectional (but possibly multi-styled) run of text. |
| * |
| * |
| * @param c the canvas to draw on |
| * @param start the line-relative start |
| * @param limit the line-relative limit |
| * @param runIsRtl true if the run is right-to-left |
| * @param x the position of the run that is closest to the leading margin |
| * @param top the top of the line |
| * @param y the baseline |
| * @param bottom the bottom of the line |
| * @param needWidth true if the width value is required. |
| * @return the signed width of the run, based on the paragraph direction. |
| * Only valid if needWidth is true. |
| */ |
| private float drawRun(Canvas c, int start, |
| int limit, boolean runIsRtl, float x, int top, int y, int bottom, |
| boolean needWidth) { |
| |
| if ((mDir == Layout.DIR_LEFT_TO_RIGHT) == runIsRtl) { |
| float w = -measureRun(start, limit, limit, runIsRtl, null); |
| handleRun(start, limit, limit, runIsRtl, c, x + w, top, |
| y, bottom, null, false); |
| return w; |
| } |
| |
| return handleRun(start, limit, limit, runIsRtl, c, x, top, |
| y, bottom, null, needWidth); |
| } |
| |
| /** |
| * Measures a unidirectional (but possibly multi-styled) run of text. |
| * |
| * |
| * @param start the line-relative start of the run |
| * @param offset the offset to measure to, between start and limit inclusive |
| * @param limit the line-relative limit of the run |
| * @param runIsRtl true if the run is right-to-left |
| * @param fmi receives metrics information about the requested |
| * run, can be null. |
| * @return the signed width from the start of the run to the leading edge |
| * of the character at offset, based on the run (not paragraph) direction |
| */ |
| private float measureRun(int start, int offset, int limit, boolean runIsRtl, |
| FontMetricsInt fmi) { |
| return handleRun(start, offset, limit, runIsRtl, null, 0, 0, 0, 0, fmi, true); |
| } |
| |
| /** |
| * Walk the cursor through this line, skipping conjuncts and |
| * zero-width characters. |
| * |
| * <p>This function cannot properly walk the cursor off the ends of the line |
| * since it does not know about any shaping on the previous/following line |
| * that might affect the cursor position. Callers must either avoid these |
| * situations or handle the result specially. |
| * |
| * @param cursor the starting position of the cursor, between 0 and the |
| * length of the line, inclusive |
| * @param toLeft true if the caret is moving to the left. |
| * @return the new offset. If it is less than 0 or greater than the length |
| * of the line, the previous/following line should be examined to get the |
| * actual offset. |
| */ |
| int getOffsetToLeftRightOf(int cursor, boolean toLeft) { |
| // 1) The caret marks the leading edge of a character. The character |
| // logically before it might be on a different level, and the active caret |
| // position is on the character at the lower level. If that character |
| // was the previous character, the caret is on its trailing edge. |
| // 2) Take this character/edge and move it in the indicated direction. |
| // This gives you a new character and a new edge. |
| // 3) This position is between two visually adjacent characters. One of |
| // these might be at a lower level. The active position is on the |
| // character at the lower level. |
| // 4) If the active position is on the trailing edge of the character, |
| // the new caret position is the following logical character, else it |
| // is the character. |
| |
| int lineStart = 0; |
| int lineEnd = mLen; |
| boolean paraIsRtl = mDir == -1; |
| int[] runs = mDirections.mDirections; |
| |
| int runIndex, runLevel = 0, runStart = lineStart, runLimit = lineEnd, newCaret = -1; |
| boolean trailing = false; |
| |
| if (cursor == lineStart) { |
| runIndex = -2; |
| } else if (cursor == lineEnd) { |
| runIndex = runs.length; |
| } else { |
| // First, get information about the run containing the character with |
| // the active caret. |
| for (runIndex = 0; runIndex < runs.length; runIndex += 2) { |
| runStart = lineStart + runs[runIndex]; |
| if (cursor >= runStart) { |
| runLimit = runStart + (runs[runIndex+1] & Layout.RUN_LENGTH_MASK); |
| if (runLimit > lineEnd) { |
| runLimit = lineEnd; |
| } |
| if (cursor < runLimit) { |
| runLevel = (runs[runIndex+1] >>> Layout.RUN_LEVEL_SHIFT) & |
| Layout.RUN_LEVEL_MASK; |
| if (cursor == runStart) { |
| // The caret is on a run boundary, see if we should |
| // use the position on the trailing edge of the previous |
| // logical character instead. |
| int prevRunIndex, prevRunLevel, prevRunStart, prevRunLimit; |
| int pos = cursor - 1; |
| for (prevRunIndex = 0; prevRunIndex < runs.length; prevRunIndex += 2) { |
| prevRunStart = lineStart + runs[prevRunIndex]; |
| if (pos >= prevRunStart) { |
| prevRunLimit = prevRunStart + |
| (runs[prevRunIndex+1] & Layout.RUN_LENGTH_MASK); |
| if (prevRunLimit > lineEnd) { |
| prevRunLimit = lineEnd; |
| } |
| if (pos < prevRunLimit) { |
| prevRunLevel = (runs[prevRunIndex+1] >>> Layout.RUN_LEVEL_SHIFT) |
| & Layout.RUN_LEVEL_MASK; |
| if (prevRunLevel < runLevel) { |
| // Start from logically previous character. |
| runIndex = prevRunIndex; |
| runLevel = prevRunLevel; |
| runStart = prevRunStart; |
| runLimit = prevRunLimit; |
| trailing = true; |
| break; |
| } |
| } |
| } |
| } |
| } |
| break; |
| } |
| } |
| } |
| |
| // caret might be == lineEnd. This is generally a space or paragraph |
| // separator and has an associated run, but might be the end of |
| // text, in which case it doesn't. If that happens, we ran off the |
| // end of the run list, and runIndex == runs.length. In this case, |
| // we are at a run boundary so we skip the below test. |
| if (runIndex != runs.length) { |
| boolean runIsRtl = (runLevel & 0x1) != 0; |
| boolean advance = toLeft == runIsRtl; |
| if (cursor != (advance ? runLimit : runStart) || advance != trailing) { |
| // Moving within or into the run, so we can move logically. |
| newCaret = getOffsetBeforeAfter(runIndex, runStart, runLimit, |
| runIsRtl, cursor, advance); |
| // If the new position is internal to the run, we're at the strong |
| // position already so we're finished. |
| if (newCaret != (advance ? runLimit : runStart)) { |
| return newCaret; |
| } |
| } |
| } |
| } |
| |
| // If newCaret is -1, we're starting at a run boundary and crossing |
| // into another run. Otherwise we've arrived at a run boundary, and |
| // need to figure out which character to attach to. Note we might |
| // need to run this twice, if we cross a run boundary and end up at |
| // another run boundary. |
| while (true) { |
| boolean advance = toLeft == paraIsRtl; |
| int otherRunIndex = runIndex + (advance ? 2 : -2); |
| if (otherRunIndex >= 0 && otherRunIndex < runs.length) { |
| int otherRunStart = lineStart + runs[otherRunIndex]; |
| int otherRunLimit = otherRunStart + |
| (runs[otherRunIndex+1] & Layout.RUN_LENGTH_MASK); |
| if (otherRunLimit > lineEnd) { |
| otherRunLimit = lineEnd; |
| } |
| int otherRunLevel = (runs[otherRunIndex+1] >>> Layout.RUN_LEVEL_SHIFT) & |
| Layout.RUN_LEVEL_MASK; |
| boolean otherRunIsRtl = (otherRunLevel & 1) != 0; |
| |
| advance = toLeft == otherRunIsRtl; |
| if (newCaret == -1) { |
| newCaret = getOffsetBeforeAfter(otherRunIndex, otherRunStart, |
| otherRunLimit, otherRunIsRtl, |
| advance ? otherRunStart : otherRunLimit, advance); |
| if (newCaret == (advance ? otherRunLimit : otherRunStart)) { |
| // Crossed and ended up at a new boundary, |
| // repeat a second and final time. |
| runIndex = otherRunIndex; |
| runLevel = otherRunLevel; |
| continue; |
| } |
| break; |
| } |
| |
| // The new caret is at a boundary. |
| if (otherRunLevel < runLevel) { |
| // The strong character is in the other run. |
| newCaret = advance ? otherRunStart : otherRunLimit; |
| } |
| break; |
| } |
| |
| if (newCaret == -1) { |
| // We're walking off the end of the line. The paragraph |
| // level is always equal to or lower than any internal level, so |
| // the boundaries get the strong caret. |
| newCaret = advance ? mLen + 1 : -1; |
| break; |
| } |
| |
| // Else we've arrived at the end of the line. That's a strong position. |
| // We might have arrived here by crossing over a run with no internal |
| // breaks and dropping out of the above loop before advancing one final |
| // time, so reset the caret. |
| // Note, we use '<=' below to handle a situation where the only run |
| // on the line is a counter-directional run. If we're not advancing, |
| // we can end up at the 'lineEnd' position but the caret we want is at |
| // the lineStart. |
| if (newCaret <= lineEnd) { |
| newCaret = advance ? lineEnd : lineStart; |
| } |
| break; |
| } |
| |
| return newCaret; |
| } |
| |
| /** |
| * Returns the next valid offset within this directional run, skipping |
| * conjuncts and zero-width characters. This should not be called to walk |
| * off the end of the line, since the returned values might not be valid |
| * on neighboring lines. If the returned offset is less than zero or |
| * greater than the line length, the offset should be recomputed on the |
| * preceding or following line, respectively. |
| * |
| * @param runIndex the run index |
| * @param runStart the start of the run |
| * @param runLimit the limit of the run |
| * @param runIsRtl true if the run is right-to-left |
| * @param offset the offset |
| * @param after true if the new offset should logically follow the provided |
| * offset |
| * @return the new offset |
| */ |
| private int getOffsetBeforeAfter(int runIndex, int runStart, int runLimit, |
| boolean runIsRtl, int offset, boolean after) { |
| |
| if (runIndex < 0 || offset == (after ? mLen : 0)) { |
| // Walking off end of line. Since we don't know |
| // what cursor positions are available on other lines, we can't |
| // return accurate values. These are a guess. |
| if (after) { |
| return TextUtils.getOffsetAfter(mText, offset + mStart) - mStart; |
| } |
| return TextUtils.getOffsetBefore(mText, offset + mStart) - mStart; |
| } |
| |
| TextPaint wp = mWorkPaint; |
| wp.set(mPaint); |
| if (mIsJustifying) { |
| wp.setWordSpacing(mAddedWidthForJustify); |
| } |
| |
| int spanStart = runStart; |
| int spanLimit; |
| if (mSpanned == null) { |
| spanLimit = runLimit; |
| } else { |
| int target = after ? offset + 1 : offset; |
| int limit = mStart + runLimit; |
| while (true) { |
| spanLimit = mSpanned.nextSpanTransition(mStart + spanStart, limit, |
| MetricAffectingSpan.class) - mStart; |
| if (spanLimit >= target) { |
| break; |
| } |
| spanStart = spanLimit; |
| } |
| |
| MetricAffectingSpan[] spans = mSpanned.getSpans(mStart + spanStart, |
| mStart + spanLimit, MetricAffectingSpan.class); |
| spans = TextUtils.removeEmptySpans(spans, mSpanned, MetricAffectingSpan.class); |
| |
| if (spans.length > 0) { |
| ReplacementSpan replacement = null; |
| for (int j = 0; j < spans.length; j++) { |
| MetricAffectingSpan span = spans[j]; |
| if (span instanceof ReplacementSpan) { |
| replacement = (ReplacementSpan)span; |
| } else { |
| span.updateMeasureState(wp); |
| } |
| } |
| |
| if (replacement != null) { |
| // If we have a replacement span, we're moving either to |
| // the start or end of this span. |
| return after ? spanLimit : spanStart; |
| } |
| } |
| } |
| |
| int cursorOpt = after ? Paint.CURSOR_AFTER : Paint.CURSOR_BEFORE; |
| if (mCharsValid) { |
| return wp.getTextRunCursor(mChars, spanStart, spanLimit - spanStart, |
| runIsRtl, offset, cursorOpt); |
| } else { |
| return wp.getTextRunCursor(mText, mStart + spanStart, |
| mStart + spanLimit, runIsRtl, mStart + offset, cursorOpt) - mStart; |
| } |
| } |
| |
| /** |
| * @param wp |
| */ |
| private static void expandMetricsFromPaint(FontMetricsInt fmi, TextPaint wp) { |
| final int previousTop = fmi.top; |
| final int previousAscent = fmi.ascent; |
| final int previousDescent = fmi.descent; |
| final int previousBottom = fmi.bottom; |
| final int previousLeading = fmi.leading; |
| |
| wp.getFontMetricsInt(fmi); |
| |
| updateMetrics(fmi, previousTop, previousAscent, previousDescent, previousBottom, |
| previousLeading); |
| } |
| |
| static void updateMetrics(FontMetricsInt fmi, int previousTop, int previousAscent, |
| int previousDescent, int previousBottom, int previousLeading) { |
| fmi.top = Math.min(fmi.top, previousTop); |
| fmi.ascent = Math.min(fmi.ascent, previousAscent); |
| fmi.descent = Math.max(fmi.descent, previousDescent); |
| fmi.bottom = Math.max(fmi.bottom, previousBottom); |
| fmi.leading = Math.max(fmi.leading, previousLeading); |
| } |
| |
| private static void drawStroke(TextPaint wp, Canvas c, int color, float position, |
| float thickness, float xleft, float xright, float baseline) { |
| final float strokeTop = baseline + wp.baselineShift + position; |
| |
| final int previousColor = wp.getColor(); |
| final Paint.Style previousStyle = wp.getStyle(); |
| final boolean previousAntiAlias = wp.isAntiAlias(); |
| |
| wp.setStyle(Paint.Style.FILL); |
| wp.setAntiAlias(true); |
| |
| wp.setColor(color); |
| c.drawRect(xleft, strokeTop, xright, strokeTop + thickness, wp); |
| |
| wp.setStyle(previousStyle); |
| wp.setColor(previousColor); |
| wp.setAntiAlias(previousAntiAlias); |
| } |
| |
| private float getRunAdvance(TextPaint wp, int start, int end, int contextStart, int contextEnd, |
| boolean runIsRtl, int offset) { |
| if (mCharsValid) { |
| return wp.getRunAdvance(mChars, start, end, contextStart, contextEnd, runIsRtl, offset); |
| } else { |
| final int delta = mStart; |
| if (mComputed == null) { |
| return wp.getRunAdvance(mText, delta + start, delta + end, |
| delta + contextStart, delta + contextEnd, runIsRtl, delta + offset); |
| } else { |
| return mComputed.getWidth(start + delta, end + delta); |
| } |
| } |
| } |
| |
| /** |
| * Utility function for measuring and rendering text. The text must |
| * not include a tab. |
| * |
| * @param wp the working paint |
| * @param start the start of the text |
| * @param end the end of the text |
| * @param runIsRtl true if the run is right-to-left |
| * @param c the canvas, can be null if rendering is not needed |
| * @param x the edge of the run closest to the leading margin |
| * @param top the top of the line |
| * @param y the baseline |
| * @param bottom the bottom of the line |
| * @param fmi receives metrics information, can be null |
| * @param needWidth true if the width of the run is needed |
| * @param offset the offset for the purpose of measuring |
| * @param decorations the list of locations and paremeters for drawing decorations |
| * @return the signed width of the run based on the run direction; only |
| * valid if needWidth is true |
| */ |
| private float handleText(TextPaint wp, int start, int end, |
| int contextStart, int contextEnd, boolean runIsRtl, |
| Canvas c, float x, int top, int y, int bottom, |
| FontMetricsInt fmi, boolean needWidth, int offset, |
| @Nullable ArrayList<DecorationInfo> decorations) { |
| |
| if (mIsJustifying) { |
| wp.setWordSpacing(mAddedWidthForJustify); |
| } |
| // Get metrics first (even for empty strings or "0" width runs) |
| if (fmi != null) { |
| expandMetricsFromPaint(fmi, wp); |
| } |
| |
| // No need to do anything if the run width is "0" |
| if (end == start) { |
| return 0f; |
| } |
| |
| float totalWidth = 0; |
| |
| final int numDecorations = decorations == null ? 0 : decorations.size(); |
| if (needWidth || (c != null && (wp.bgColor != 0 || numDecorations != 0 || runIsRtl))) { |
| totalWidth = getRunAdvance(wp, start, end, contextStart, contextEnd, runIsRtl, offset); |
| } |
| |
| if (c != null) { |
| final float leftX, rightX; |
| if (runIsRtl) { |
| leftX = x - totalWidth; |
| rightX = x; |
| } else { |
| leftX = x; |
| rightX = x + totalWidth; |
| } |
| |
| if (wp.bgColor != 0) { |
| int previousColor = wp.getColor(); |
| Paint.Style previousStyle = wp.getStyle(); |
| |
| wp.setColor(wp.bgColor); |
| wp.setStyle(Paint.Style.FILL); |
| c.drawRect(leftX, top, rightX, bottom, wp); |
| |
| wp.setStyle(previousStyle); |
| wp.setColor(previousColor); |
| } |
| |
| drawTextRun(c, wp, start, end, contextStart, contextEnd, runIsRtl, |
| leftX, y + wp.baselineShift); |
| |
| if (numDecorations != 0) { |
| for (int i = 0; i < numDecorations; i++) { |
| final DecorationInfo info = decorations.get(i); |
| |
| final int decorationStart = Math.max(info.start, start); |
| final int decorationEnd = Math.min(info.end, offset); |
| float decorationStartAdvance = getRunAdvance( |
| wp, start, end, contextStart, contextEnd, runIsRtl, decorationStart); |
| float decorationEndAdvance = getRunAdvance( |
| wp, start, end, contextStart, contextEnd, runIsRtl, decorationEnd); |
| final float decorationXLeft, decorationXRight; |
| if (runIsRtl) { |
| decorationXLeft = rightX - decorationEndAdvance; |
| decorationXRight = rightX - decorationStartAdvance; |
| } else { |
| decorationXLeft = leftX + decorationStartAdvance; |
| decorationXRight = leftX + decorationEndAdvance; |
| } |
| |
| // Theoretically, there could be cases where both Paint's and TextPaint's |
| // setUnderLineText() are called. For backward compatibility, we need to draw |
| // both underlines, the one with custom color first. |
| if (info.underlineColor != 0) { |
| drawStroke(wp, c, info.underlineColor, wp.getUnderlinePosition(), |
| info.underlineThickness, decorationXLeft, decorationXRight, y); |
| } |
| if (info.isUnderlineText) { |
| final float thickness = |
| Math.max(wp.getUnderlineThickness(), 1.0f); |
| drawStroke(wp, c, wp.getColor(), wp.getUnderlinePosition(), thickness, |
| decorationXLeft, decorationXRight, y); |
| } |
| |
| if (info.isStrikeThruText) { |
| final float thickness = |
| Math.max(wp.getStrikeThruThickness(), 1.0f); |
| drawStroke(wp, c, wp.getColor(), wp.getStrikeThruPosition(), thickness, |
| decorationXLeft, decorationXRight, y); |
| } |
| } |
| } |
| |
| } |
| |
| return runIsRtl ? -totalWidth : totalWidth; |
| } |
| |
| /** |
| * Utility function for measuring and rendering a replacement. |
| * |
| * |
| * @param replacement the replacement |
| * @param wp the work paint |
| * @param start the start of the run |
| * @param limit the limit of the run |
| * @param runIsRtl true if the run is right-to-left |
| * @param c the canvas, can be null if not rendering |
| * @param x the edge of the replacement closest to the leading margin |
| * @param top the top of the line |
| * @param y the baseline |
| * @param bottom the bottom of the line |
| * @param fmi receives metrics information, can be null |
| * @param needWidth true if the width of the replacement is needed |
| * @return the signed width of the run based on the run direction; only |
| * valid if needWidth is true |
| */ |
| private float handleReplacement(ReplacementSpan replacement, TextPaint wp, |
| int start, int limit, boolean runIsRtl, Canvas c, |
| float x, int top, int y, int bottom, FontMetricsInt fmi, |
| boolean needWidth) { |
| |
| float ret = 0; |
| |
| int textStart = mStart + start; |
| int textLimit = mStart + limit; |
| |
| if (needWidth || (c != null && runIsRtl)) { |
| int previousTop = 0; |
| int previousAscent = 0; |
| int previousDescent = 0; |
| int previousBottom = 0; |
| int previousLeading = 0; |
| |
| boolean needUpdateMetrics = (fmi != null); |
| |
| if (needUpdateMetrics) { |
| previousTop = fmi.top; |
| previousAscent = fmi.ascent; |
| previousDescent = fmi.descent; |
| previousBottom = fmi.bottom; |
| previousLeading = fmi.leading; |
| } |
| |
| ret = replacement.getSize(wp, mText, textStart, textLimit, fmi); |
| |
| if (needUpdateMetrics) { |
| updateMetrics(fmi, previousTop, previousAscent, previousDescent, previousBottom, |
| previousLeading); |
| } |
| } |
| |
| if (c != null) { |
| if (runIsRtl) { |
| x -= ret; |
| } |
| replacement.draw(c, mText, textStart, textLimit, |
| x, top, y, bottom, wp); |
| } |
| |
| return runIsRtl ? -ret : ret; |
| } |
| |
| private int adjustStartHyphenEdit(int start, @Paint.StartHyphenEdit int startHyphenEdit) { |
| // Only draw hyphens on first in line. Disable them otherwise. |
| return start > 0 ? Paint.START_HYPHEN_EDIT_NO_EDIT : startHyphenEdit; |
| } |
| |
| private int adjustEndHyphenEdit(int limit, @Paint.EndHyphenEdit int endHyphenEdit) { |
| // Only draw hyphens on last run in line. Disable them otherwise. |
| return limit < mLen ? Paint.END_HYPHEN_EDIT_NO_EDIT : endHyphenEdit; |
| } |
| |
| private static final class DecorationInfo { |
| public boolean isStrikeThruText; |
| public boolean isUnderlineText; |
| public int underlineColor; |
| public float underlineThickness; |
| public int start = -1; |
| public int end = -1; |
| |
| public boolean hasDecoration() { |
| return isStrikeThruText || isUnderlineText || underlineColor != 0; |
| } |
| |
| // Copies the info, but not the start and end range. |
| public DecorationInfo copyInfo() { |
| final DecorationInfo copy = new DecorationInfo(); |
| copy.isStrikeThruText = isStrikeThruText; |
| copy.isUnderlineText = isUnderlineText; |
| copy.underlineColor = underlineColor; |
| copy.underlineThickness = underlineThickness; |
| return copy; |
| } |
| } |
| |
| private void extractDecorationInfo(@NonNull TextPaint paint, @NonNull DecorationInfo info) { |
| info.isStrikeThruText = paint.isStrikeThruText(); |
| if (info.isStrikeThruText) { |
| paint.setStrikeThruText(false); |
| } |
| info.isUnderlineText = paint.isUnderlineText(); |
| if (info.isUnderlineText) { |
| paint.setUnderlineText(false); |
| } |
| info.underlineColor = paint.underlineColor; |
| info.underlineThickness = paint.underlineThickness; |
| paint.setUnderlineText(0, 0.0f); |
| } |
| |
| /** |
| * Utility function for handling a unidirectional run. The run must not |
| * contain tabs but can contain styles. |
| * |
| * |
| * @param start the line-relative start of the run |
| * @param measureLimit the offset to measure to, between start and limit inclusive |
| * @param limit the limit of the run |
| * @param runIsRtl true if the run is right-to-left |
| * @param c the canvas, can be null |
| * @param x the end of the run closest to the leading margin |
| * @param top the top of the line |
| * @param y the baseline |
| * @param bottom the bottom of the line |
| * @param fmi receives metrics information, can be null |
| * @param needWidth true if the width is required |
| * @return the signed width of the run based on the run direction; only |
| * valid if needWidth is true |
| */ |
| private float handleRun(int start, int measureLimit, |
| int limit, boolean runIsRtl, Canvas c, float x, int top, int y, |
| int bottom, FontMetricsInt fmi, boolean needWidth) { |
| |
| if (measureLimit < start || measureLimit > limit) { |
| throw new IndexOutOfBoundsException("measureLimit (" + measureLimit + ") is out of " |
| + "start (" + start + ") and limit (" + limit + ") bounds"); |
| } |
| |
| // Case of an empty line, make sure we update fmi according to mPaint |
| if (start == measureLimit) { |
| final TextPaint wp = mWorkPaint; |
| wp.set(mPaint); |
| if (fmi != null) { |
| expandMetricsFromPaint(fmi, wp); |
| } |
| return 0f; |
| } |
| |
| final boolean needsSpanMeasurement; |
| if (mSpanned == null) { |
| needsSpanMeasurement = false; |
| } else { |
| mMetricAffectingSpanSpanSet.init(mSpanned, mStart + start, mStart + limit); |
| mCharacterStyleSpanSet.init(mSpanned, mStart + start, mStart + limit); |
| needsSpanMeasurement = mMetricAffectingSpanSpanSet.numberOfSpans != 0 |
| || mCharacterStyleSpanSet.numberOfSpans != 0; |
| } |
| |
| if (!needsSpanMeasurement) { |
| final TextPaint wp = mWorkPaint; |
| wp.set(mPaint); |
| wp.setStartHyphenEdit(adjustStartHyphenEdit(start, wp.getStartHyphenEdit())); |
| wp.setEndHyphenEdit(adjustEndHyphenEdit(limit, wp.getEndHyphenEdit())); |
| return handleText(wp, start, limit, start, limit, runIsRtl, c, x, top, |
| y, bottom, fmi, needWidth, measureLimit, null); |
| } |
| |
| // Shaping needs to take into account context up to metric boundaries, |
| // but rendering needs to take into account character style boundaries. |
| // So we iterate through metric runs to get metric bounds, |
| // then within each metric run iterate through character style runs |
| // for the run bounds. |
| final float originalX = x; |
| for (int i = start, inext; i < measureLimit; i = inext) { |
| final TextPaint wp = mWorkPaint; |
| wp.set(mPaint); |
| |
| inext = mMetricAffectingSpanSpanSet.getNextTransition(mStart + i, mStart + limit) - |
| mStart; |
| int mlimit = Math.min(inext, measureLimit); |
| |
| ReplacementSpan replacement = null; |
| |
| for (int j = 0; j < mMetricAffectingSpanSpanSet.numberOfSpans; j++) { |
| // Both intervals [spanStarts..spanEnds] and [mStart + i..mStart + mlimit] are NOT |
| // empty by construction. This special case in getSpans() explains the >= & <= tests |
| if ((mMetricAffectingSpanSpanSet.spanStarts[j] >= mStart + mlimit) |
| || (mMetricAffectingSpanSpanSet.spanEnds[j] <= mStart + i)) continue; |
| |
| boolean insideEllipsis = |
| mStart + mEllipsisStart <= mMetricAffectingSpanSpanSet.spanStarts[j] |
| && mMetricAffectingSpanSpanSet.spanEnds[j] <= mStart + mEllipsisEnd; |
| final MetricAffectingSpan span = mMetricAffectingSpanSpanSet.spans[j]; |
| if (span instanceof ReplacementSpan) { |
| replacement = !insideEllipsis ? (ReplacementSpan) span : null; |
| } else { |
| // We might have a replacement that uses the draw |
| // state, otherwise measure state would suffice. |
| span.updateDrawState(wp); |
| } |
| } |
| |
| if (replacement != null) { |
| x += handleReplacement(replacement, wp, i, mlimit, runIsRtl, c, x, top, y, |
| bottom, fmi, needWidth || mlimit < measureLimit); |
| continue; |
| } |
| |
| final TextPaint activePaint = mActivePaint; |
| activePaint.set(mPaint); |
| int activeStart = i; |
| int activeEnd = mlimit; |
| final DecorationInfo decorationInfo = mDecorationInfo; |
| mDecorations.clear(); |
| for (int j = i, jnext; j < mlimit; j = jnext) { |
| jnext = mCharacterStyleSpanSet.getNextTransition(mStart + j, mStart + inext) - |
| mStart; |
| |
| final int offset = Math.min(jnext, mlimit); |
| wp.set(mPaint); |
| for (int k = 0; k < mCharacterStyleSpanSet.numberOfSpans; k++) { |
| // Intentionally using >= and <= as explained above |
| if ((mCharacterStyleSpanSet.spanStarts[k] >= mStart + offset) || |
| (mCharacterStyleSpanSet.spanEnds[k] <= mStart + j)) continue; |
| |
| final CharacterStyle span = mCharacterStyleSpanSet.spans[k]; |
| span.updateDrawState(wp); |
| } |
| |
| extractDecorationInfo(wp, decorationInfo); |
| |
| if (j == i) { |
| // First chunk of text. We can't handle it yet, since we may need to merge it |
| // with the next chunk. So we just save the TextPaint for future comparisons |
| // and use. |
| activePaint.set(wp); |
| } else if (!equalAttributes(wp, activePaint)) { |
| // The style of the present chunk of text is substantially different from the |
| // style of the previous chunk. We need to handle the active piece of text |
| // and restart with the present chunk. |
| activePaint.setStartHyphenEdit( |
| adjustStartHyphenEdit(activeStart, mPaint.getStartHyphenEdit())); |
| activePaint.setEndHyphenEdit( |
| adjustEndHyphenEdit(activeEnd, mPaint.getEndHyphenEdit())); |
| x += handleText(activePaint, activeStart, activeEnd, i, inext, runIsRtl, c, x, |
| top, y, bottom, fmi, needWidth || activeEnd < measureLimit, |
| Math.min(activeEnd, mlimit), mDecorations); |
| |
| activeStart = j; |
| activePaint.set(wp); |
| mDecorations.clear(); |
| } else { |
| // The present TextPaint is substantially equal to the last TextPaint except |
| // perhaps for decorations. We just need to expand the active piece of text to |
| // include the present chunk, which we always do anyway. We don't need to save |
| // wp to activePaint, since they are already equal. |
| } |
| |
| activeEnd = jnext; |
| if (decorationInfo.hasDecoration()) { |
| final DecorationInfo copy = decorationInfo.copyInfo(); |
| copy.start = j; |
| copy.end = jnext; |
| mDecorations.add(copy); |
| } |
| } |
| // Handle the final piece of text. |
| activePaint.setStartHyphenEdit( |
| adjustStartHyphenEdit(activeStart, mPaint.getStartHyphenEdit())); |
| activePaint.setEndHyphenEdit( |
| adjustEndHyphenEdit(activeEnd, mPaint.getEndHyphenEdit())); |
| x += handleText(activePaint, activeStart, activeEnd, i, inext, runIsRtl, c, x, |
| top, y, bottom, fmi, needWidth || activeEnd < measureLimit, |
| Math.min(activeEnd, mlimit), mDecorations); |
| } |
| |
| return x - originalX; |
| } |
| |
| /** |
| * Render a text run with the set-up paint. |
| * |
| * @param c the canvas |
| * @param wp the paint used to render the text |
| * @param start the start of the run |
| * @param end the end of the run |
| * @param contextStart the start of context for the run |
| * @param contextEnd the end of the context for the run |
| * @param runIsRtl true if the run is right-to-left |
| * @param x the x position of the left edge of the run |
| * @param y the baseline of the run |
| */ |
| private void drawTextRun(Canvas c, TextPaint wp, int start, int end, |
| int contextStart, int contextEnd, boolean runIsRtl, float x, int y) { |
| |
| if (mCharsValid) { |
| int count = end - start; |
| int contextCount = contextEnd - contextStart; |
| c.drawTextRun(mChars, start, count, contextStart, contextCount, |
| x, y, runIsRtl, wp); |
| } else { |
| int delta = mStart; |
| c.drawTextRun(mText, delta + start, delta + end, |
| delta + contextStart, delta + contextEnd, x, y, runIsRtl, wp); |
| } |
| } |
| |
| /** |
| * Returns the next tab position. |
| * |
| * @param h the (unsigned) offset from the leading margin |
| * @return the (unsigned) tab position after this offset |
| */ |
| float nextTab(float h) { |
| if (mTabs != null) { |
| return mTabs.nextTab(h); |
| } |
| return TabStops.nextDefaultStop(h, TAB_INCREMENT); |
| } |
| |
| private boolean isStretchableWhitespace(int ch) { |
| // TODO: Support NBSP and other stretchable whitespace (b/34013491 and b/68204709). |
| return ch == 0x0020; |
| } |
| |
| /* Return the number of spaces in the text line, for the purpose of justification */ |
| private int countStretchableSpaces(int start, int end) { |
| int count = 0; |
| for (int i = start; i < end; i++) { |
| final char c = mCharsValid ? mChars[i] : mText.charAt(i + mStart); |
| if (isStretchableWhitespace(c)) { |
| count++; |
| } |
| } |
| return count; |
| } |
| |
| // Note: keep this in sync with Minikin LineBreaker::isLineEndSpace() |
| public static boolean isLineEndSpace(char ch) { |
| return ch == ' ' || ch == '\t' || ch == 0x1680 |
| || (0x2000 <= ch && ch <= 0x200A && ch != 0x2007) |
| || ch == 0x205F || ch == 0x3000; |
| } |
| |
| private static final int TAB_INCREMENT = 20; |
| |
| private static boolean equalAttributes(@NonNull TextPaint lp, @NonNull TextPaint rp) { |
| return lp.getColorFilter() == rp.getColorFilter() |
| && lp.getMaskFilter() == rp.getMaskFilter() |
| && lp.getShader() == rp.getShader() |
| && lp.getTypeface() == rp.getTypeface() |
| && lp.getXfermode() == rp.getXfermode() |
| && lp.getTextLocales().equals(rp.getTextLocales()) |
| && TextUtils.equals(lp.getFontFeatureSettings(), rp.getFontFeatureSettings()) |
| && TextUtils.equals(lp.getFontVariationSettings(), rp.getFontVariationSettings()) |
| && lp.getShadowLayerRadius() == rp.getShadowLayerRadius() |
| && lp.getShadowLayerDx() == rp.getShadowLayerDx() |
| && lp.getShadowLayerDy() == rp.getShadowLayerDy() |
| && lp.getShadowLayerColor() == rp.getShadowLayerColor() |
| && lp.getFlags() == rp.getFlags() |
| && lp.getHinting() == rp.getHinting() |
| && lp.getStyle() == rp.getStyle() |
| && lp.getColor() == rp.getColor() |
| && lp.getStrokeWidth() == rp.getStrokeWidth() |
| && lp.getStrokeMiter() == rp.getStrokeMiter() |
| && lp.getStrokeCap() == rp.getStrokeCap() |
| && lp.getStrokeJoin() == rp.getStrokeJoin() |
| && lp.getTextAlign() == rp.getTextAlign() |
| && lp.isElegantTextHeight() == rp.isElegantTextHeight() |
| && lp.getTextSize() == rp.getTextSize() |
| && lp.getTextScaleX() == rp.getTextScaleX() |
| && lp.getTextSkewX() == rp.getTextSkewX() |
| && lp.getLetterSpacing() == rp.getLetterSpacing() |
| && lp.getWordSpacing() == rp.getWordSpacing() |
| && lp.getStartHyphenEdit() == rp.getStartHyphenEdit() |
| && lp.getEndHyphenEdit() == rp.getEndHyphenEdit() |
| && lp.bgColor == rp.bgColor |
| && lp.baselineShift == rp.baselineShift |
| && lp.linkColor == rp.linkColor |
| && lp.drawableState == rp.drawableState |
| && lp.density == rp.density |
| && lp.underlineColor == rp.underlineColor |
| && lp.underlineThickness == rp.underlineThickness; |
| } |
| } |
