diff options
Diffstat (limited to 'src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java')
-rw-r--r-- | src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java b/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java new file mode 100644 index 000000000..2c4184dc4 --- /dev/null +++ b/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java @@ -0,0 +1,235 @@ +/* + * Copyright (C) 2015 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 com.android.launcher3; + +import android.animation.AnimatorSet; +import android.animation.ArgbEvaluator; +import android.animation.ObjectAnimator; +import android.animation.ValueAnimator; +import android.content.res.Resources; +import android.graphics.Canvas; +import android.graphics.Color; +import android.graphics.Paint; +import android.graphics.Point; +import android.graphics.Rect; +import android.view.MotionEvent; +import android.view.ViewConfiguration; + +import com.android.launcher3.util.Thunk; + +/** + * The track and scrollbar that shows when you scroll the list. + */ +public class BaseRecyclerViewFastScrollBar { + + public interface FastScrollFocusableView { + void setFastScrollFocused(boolean focused, boolean animated); + } + + private final static int MAX_TRACK_ALPHA = 30; + private final static int SCROLL_BAR_VIS_DURATION = 150; + + @Thunk BaseRecyclerView mRv; + private BaseRecyclerViewFastScrollPopup mPopup; + + private AnimatorSet mScrollbarAnimator; + + private int mThumbInactiveColor; + private int mThumbActiveColor; + @Thunk Point mThumbOffset = new Point(-1, -1); + @Thunk Paint mThumbPaint; + private Paint mTrackPaint; + private int mThumbMinWidth; + private int mThumbMaxWidth; + @Thunk int mThumbWidth; + @Thunk int mThumbHeight; + // The inset is the buffer around which a point will still register as a click on the scrollbar + private int mTouchInset; + private boolean mIsDragging; + + // This is the offset from the top of the scrollbar when the user first starts touching. To + // prevent jumping, this offset is applied as the user scrolls. + private int mTouchOffset; + + private Rect mInvalidateRect = new Rect(); + private Rect mTmpRect = new Rect(); + + public BaseRecyclerViewFastScrollBar(BaseRecyclerView rv, Resources res) { + mRv = rv; + mPopup = new BaseRecyclerViewFastScrollPopup(rv, res); + mTrackPaint = new Paint(); + mTrackPaint.setColor(rv.getFastScrollerTrackColor(Color.BLACK)); + mTrackPaint.setAlpha(0); + mThumbInactiveColor = rv.getFastScrollerThumbInactiveColor( + res.getColor(R.color.container_fastscroll_thumb_inactive_color)); + mThumbActiveColor = res.getColor(R.color.container_fastscroll_thumb_active_color); + mThumbPaint = new Paint(); + mThumbPaint.setColor(mThumbInactiveColor); + mThumbWidth = mThumbMinWidth = res.getDimensionPixelSize(R.dimen.container_fastscroll_thumb_min_width); + mThumbMaxWidth = res.getDimensionPixelSize(R.dimen.container_fastscroll_thumb_max_width); + mThumbHeight = res.getDimensionPixelSize(R.dimen.container_fastscroll_thumb_height); + mTouchInset = res.getDimensionPixelSize(R.dimen.container_fastscroll_thumb_touch_inset); + } + + public void setScrollbarThumbOffset(int x, int y) { + if (mThumbOffset.x == x && mThumbOffset.y == y) { + return; + } + mInvalidateRect.set(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, mRv.getHeight()); + mThumbOffset.set(x, y); + mInvalidateRect.union(new Rect(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, + mRv.getHeight())); + mRv.invalidate(mInvalidateRect); + } + + // Setter/getter for the search bar width for animations + public void setWidth(int width) { + mInvalidateRect.set(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, mRv.getHeight()); + mThumbWidth = width; + mInvalidateRect.union(new Rect(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, + mRv.getHeight())); + mRv.invalidate(mInvalidateRect); + } + + public int getWidth() { + return mThumbWidth; + } + + // Setter/getter for the track background alpha for animations + public void setTrackAlpha(int alpha) { + mTrackPaint.setAlpha(alpha); + mInvalidateRect.set(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, mRv.getHeight()); + mRv.invalidate(mInvalidateRect); + } + + public int getTrackAlpha() { + return mTrackPaint.getAlpha(); + } + + public int getThumbHeight() { + return mThumbHeight; + } + + public int getThumbMaxWidth() { + return mThumbMaxWidth; + } + + public boolean isDragging() { + return mIsDragging; + } + + /** + * Handles the touch event and determines whether to show the fast scroller (or updates it if + * it is already showing). + */ + public void handleTouchEvent(MotionEvent ev, int downX, int downY, int lastY) { + ViewConfiguration config = ViewConfiguration.get(mRv.getContext()); + + int action = ev.getAction(); + int y = (int) ev.getY(); + switch (action) { + case MotionEvent.ACTION_DOWN: + if (isNearPoint(downX, downY)) { + mTouchOffset = downY - mThumbOffset.y; + } + break; + case MotionEvent.ACTION_MOVE: + // Check if we should start scrolling + if (!mIsDragging && isNearPoint(downX, downY) && + Math.abs(y - downY) > config.getScaledTouchSlop()) { + mRv.getParent().requestDisallowInterceptTouchEvent(true); + mIsDragging = true; + mTouchOffset += (lastY - downY); + mPopup.animateVisibility(true); + animateScrollbar(true); + } + if (mIsDragging) { + // Update the fastscroller section name at this touch position + int top = mRv.getBackgroundPadding().top; + int bottom = mRv.getHeight() - mRv.getBackgroundPadding().bottom - mThumbHeight; + float boundedY = (float) Math.max(top, Math.min(bottom, y - mTouchOffset)); + String sectionName = mRv.scrollToPositionAtProgress((boundedY - top) / + (bottom - top)); + mPopup.setSectionName(sectionName); + mPopup.animateVisibility(!sectionName.isEmpty()); + mRv.invalidate(mPopup.updateFastScrollerBounds(mRv, lastY)); + } + break; + case MotionEvent.ACTION_UP: + case MotionEvent.ACTION_CANCEL: + mTouchOffset = 0; + if (mIsDragging) { + mIsDragging = false; + mPopup.animateVisibility(false); + animateScrollbar(false); + } + break; + } + } + + public void draw(Canvas canvas) { + if (mThumbOffset.x < 0 || mThumbOffset.y < 0) { + return; + } + + // Draw the scroll bar track and thumb + if (mTrackPaint.getAlpha() > 0) { + canvas.drawRect(mThumbOffset.x, 0, mThumbOffset.x + mThumbWidth, mRv.getHeight(), mTrackPaint); + } + canvas.drawRect(mThumbOffset.x, mThumbOffset.y, mThumbOffset.x + mThumbWidth, + mThumbOffset.y + mThumbHeight, mThumbPaint); + + // Draw the popup + mPopup.draw(canvas); + } + + /** + * Animates the width and color of the scrollbar. + */ + private void animateScrollbar(boolean isScrolling) { + if (mScrollbarAnimator != null) { + mScrollbarAnimator.cancel(); + } + ObjectAnimator trackAlphaAnim = ObjectAnimator.ofInt(this, "trackAlpha", + isScrolling ? MAX_TRACK_ALPHA : 0); + ObjectAnimator thumbWidthAnim = ObjectAnimator.ofInt(this, "width", + isScrolling ? mThumbMaxWidth : mThumbMinWidth); + ValueAnimator colorAnimation = ValueAnimator.ofObject(new ArgbEvaluator(), + mThumbPaint.getColor(), isScrolling ? mThumbActiveColor : mThumbInactiveColor); + colorAnimation.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { + @Override + public void onAnimationUpdate(ValueAnimator animator) { + mThumbPaint.setColor((Integer) animator.getAnimatedValue()); + mRv.invalidate(mThumbOffset.x, mThumbOffset.y, mThumbOffset.x + mThumbWidth, + mThumbOffset.y + mThumbHeight); + } + }); + mScrollbarAnimator = new AnimatorSet(); + mScrollbarAnimator.playTogether(trackAlphaAnim, thumbWidthAnim, colorAnimation); + mScrollbarAnimator.setDuration(SCROLL_BAR_VIS_DURATION); + mScrollbarAnimator.start(); + } + + /** + * Returns whether the specified points are near the scroll bar bounds. + */ + private boolean isNearPoint(int x, int y) { + mTmpRect.set(mThumbOffset.x, mThumbOffset.y, mThumbOffset.x + mThumbWidth, + mThumbOffset.y + mThumbHeight); + mTmpRect.inset(mTouchInset, mTouchInset); + return mTmpRect.contains(x, y); + } +} |