diff options
Diffstat (limited to 'java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java')
| -rw-r--r-- | java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java | 59 |
1 files changed, 42 insertions, 17 deletions
diff --git a/java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java b/java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java index e814d8009..7442b7fad 100644 --- a/java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java +++ b/java/src/com/android/inputmethod/keyboard/internal/GesturePreviewTrail.java @@ -17,16 +17,18 @@ package com.android.inputmethod.keyboard.internal; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Paint; +import android.graphics.PorterDuff; +import android.graphics.PorterDuffXfermode; +import android.graphics.Xfermode; import android.os.SystemClock; import com.android.inputmethod.latin.Constants; import com.android.inputmethod.latin.R; import com.android.inputmethod.latin.ResizableIntArray; -class GesturePreviewTrail { +final class GesturePreviewTrail { private static final int DEFAULT_CAPACITY = GestureStrokeWithPreviewTrail.PREVIEW_CAPACITY; - private final GesturePreviewTrailParams mPreviewParams; private final ResizableIntArray mXCoordinates = new ResizableIntArray(DEFAULT_CAPACITY); private final ResizableIntArray mYCoordinates = new ResizableIntArray(DEFAULT_CAPACITY); private final ResizableIntArray mEventTimes = new ResizableIntArray(DEFAULT_CAPACITY); @@ -34,28 +36,39 @@ class GesturePreviewTrail { private long mCurrentDownTime; private int mTrailStartIndex; + private final static Xfermode PORTER_DUFF_MODE_SRC = + new PorterDuffXfermode(PorterDuff.Mode.SRC); + // Use this value as imaginary zero because x-coordinates may be zero. private static final int DOWN_EVENT_MARKER = -128; - static class GesturePreviewTrailParams { + static final class Params { + public final int mTrailColor; + public final float mTrailStartWidth; + public final float mTrailEndWidth; public final int mFadeoutStartDelay; public final int mFadeoutDuration; public final int mUpdateInterval; - public GesturePreviewTrailParams(final TypedArray keyboardViewAttr) { + public final int mTrailLingerDuration; + + public Params(final TypedArray keyboardViewAttr) { + mTrailColor = keyboardViewAttr.getColor( + R.styleable.KeyboardView_gesturePreviewTrailColor, 0); + mTrailStartWidth = keyboardViewAttr.getDimension( + R.styleable.KeyboardView_gesturePreviewTrailStartWidth, 0.0f); + mTrailEndWidth = keyboardViewAttr.getDimension( + R.styleable.KeyboardView_gesturePreviewTrailEndWidth, 0.0f); mFadeoutStartDelay = keyboardViewAttr.getInt( R.styleable.KeyboardView_gesturePreviewTrailFadeoutStartDelay, 0); mFadeoutDuration = keyboardViewAttr.getInt( R.styleable.KeyboardView_gesturePreviewTrailFadeoutDuration, 0); + mTrailLingerDuration = mFadeoutStartDelay + mFadeoutDuration; mUpdateInterval = keyboardViewAttr.getInt( R.styleable.KeyboardView_gesturePreviewTrailUpdateInterval, 0); } } - public GesturePreviewTrail(final GesturePreviewTrailParams params) { - mPreviewParams = params; - } - private static int markAsDownEvent(final int xCoord) { return DOWN_EVENT_MARKER - xCoord; } @@ -94,23 +107,30 @@ class GesturePreviewTrail { } } - private int getAlpha(final int elapsedTime) { - if (elapsedTime < mPreviewParams.mFadeoutStartDelay) { + private static int getAlpha(final int elapsedTime, final Params params) { + if (elapsedTime < params.mFadeoutStartDelay) { return Constants.Color.ALPHA_OPAQUE; } final int decreasingAlpha = Constants.Color.ALPHA_OPAQUE - * (elapsedTime - mPreviewParams.mFadeoutStartDelay) - / mPreviewParams.mFadeoutDuration; + * (elapsedTime - params.mFadeoutStartDelay) + / params.mFadeoutDuration; return Constants.Color.ALPHA_OPAQUE - decreasingAlpha; } + private static float getWidth(final int elapsedTime, final Params params) { + return Math.max((params.mTrailLingerDuration - elapsedTime) + * (params.mTrailStartWidth - params.mTrailEndWidth) + / params.mTrailLingerDuration, 0.0f); + } + /** * Draw gesture preview trail * @param canvas The canvas to draw the gesture preview trail * @param paint The paint object to be used to draw the gesture preview trail + * @param params The drawing parameters of gesture preview trail * @return true if some gesture preview trails remain to be drawn */ - public boolean drawGestureTrail(final Canvas canvas, final Paint paint) { + public boolean drawGestureTrail(final Canvas canvas, final Paint paint, final Params params) { final int trailSize = mEventTimes.getLength(); if (trailSize == 0) { return false; @@ -120,13 +140,11 @@ class GesturePreviewTrail { final int[] xCoords = mXCoordinates.getPrimitiveArray(); final int[] yCoords = mYCoordinates.getPrimitiveArray(); final int sinceDown = (int)(SystemClock.uptimeMillis() - mCurrentDownTime); - final int lingeringDuration = mPreviewParams.mFadeoutStartDelay - + mPreviewParams.mFadeoutDuration; int startIndex; for (startIndex = mTrailStartIndex; startIndex < trailSize; startIndex++) { final int elapsedTime = sinceDown - eventTimes[startIndex]; // Skip too old trail points. - if (elapsedTime < lingeringDuration) { + if (elapsedTime < params.mTrailLingerDuration) { break; } } @@ -135,13 +153,20 @@ class GesturePreviewTrail { if (startIndex < trailSize) { int lastX = getXCoordValue(xCoords[startIndex]); int lastY = yCoords[startIndex]; + paint.setColor(params.mTrailColor); + paint.setStyle(Paint.Style.STROKE); + paint.setStrokeCap(Paint.Cap.ROUND); + paint.setXfermode(PORTER_DUFF_MODE_SRC); for (int i = startIndex + 1; i < trailSize - 1; i++) { final int x = xCoords[i]; final int y = yCoords[i]; final int elapsedTime = sinceDown - eventTimes[i]; // Draw trail line only when the current point isn't a down point. if (!isDownEventXCoord(x)) { - paint.setAlpha(getAlpha(elapsedTime)); + final int alpha = getAlpha(elapsedTime, params); + paint.setAlpha(alpha); + final float width = getWidth(elapsedTime, params); + paint.setStrokeWidth(width); canvas.drawLine(lastX, lastY, x, y, paint); } lastX = getXCoordValue(x); |