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);
+    }
+}