Merge "Updating fast scrollbar UI in Landscape" into ub-launcher3-dorval-polish

1 files changed, 356 insertions, 0 deletions

diff --git a/src/com/android/launcher3/views/RecyclerViewFastScroller.java b/src/com/android/launcher3/views/RecyclerViewFastScroller.java
new file mode 100644
index 000000000..7b5bcdbd4
--- /dev/null
+++ b/src/com/android/launcher3/views/RecyclerViewFastScroller.java
@@ -0,0 +1,356 @@
+/*
+ * Copyright (C) 2017 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.views;
+
+import android.animation.ObjectAnimator;
+import android.content.Context;
+import android.content.res.Resources;
+import android.content.res.TypedArray;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.support.v7.widget.RecyclerView;
+import android.util.AttributeSet;
+import android.util.Property;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewConfiguration;
+import android.widget.TextView;
+
+import com.android.launcher3.BaseRecyclerView;
+import com.android.launcher3.R;
+import com.android.launcher3.Utilities;
+import com.android.launcher3.config.FeatureFlags;
+import com.android.launcher3.graphics.FastScrollThumbDrawable;
+import com.android.launcher3.util.Themes;
+
+/**
+ * The track and scrollbar that shows when you scroll the list.
+ */
+public class RecyclerViewFastScroller extends View {
+
+    private static final int SCROLL_DELTA_THRESHOLD_DP = 4;
+
+    private static final Property<RecyclerViewFastScroller, Integer> TRACK_WIDTH =
+            new Property<RecyclerViewFastScroller, Integer>(Integer.class, "width") {
+
+                @Override
+                public Integer get(RecyclerViewFastScroller scrollBar) {
+                    return scrollBar.mWidth;
+                }
+
+                @Override
+                public void set(RecyclerViewFastScroller scrollBar, Integer value) {
+                    scrollBar.setTrackWidth(value);
+                }
+            };
+
+    private final static int MAX_TRACK_ALPHA = 30;
+    private final static int SCROLL_BAR_VIS_DURATION = 150;
+    private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 0.75f;
+
+    private final int mMinWidth;
+    private final int mMaxWidth;
+    private final int mThumbPadding;
+
+    /** Keeps the last known scrolling delta/velocity along y-axis. */
+    private int mDy = 0;
+    private final float mDeltaThreshold;
+
+    private final ViewConfiguration mConfig;
+
+    // Current width of the track
+    private int mWidth;
+    private ObjectAnimator mWidthAnimator;
+
+    private final Paint mThumbPaint;
+    protected final int mThumbHeight;
+
+    private final Paint mTrackPaint;
+
+    private float mLastTouchY;
+    private boolean mIsDragging;
+    private boolean mIsThumbDetached;
+    private final boolean mCanThumbDetach;
+    private boolean mIgnoreDragGesture;
+
+    // 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.
+    protected int mTouchOffsetY;
+    protected int mThumbOffsetY;
+
+    // Fast scroller popup
+    private TextView mPopupView;
+    private boolean mPopupVisible;
+    private String mPopupSectionName;
+
+    protected BaseRecyclerView mRv;
+
+    private int mDownX;
+    private int mDownY;
+    private int mLastY;
+
+    public RecyclerViewFastScroller(Context context) {
+        this(context, null);
+    }
+
+    public RecyclerViewFastScroller(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public RecyclerViewFastScroller(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+
+        mTrackPaint = new Paint();
+        mTrackPaint.setColor(Themes.getAttrColor(context, android.R.attr.textColorPrimary));
+        mTrackPaint.setAlpha(MAX_TRACK_ALPHA);
+
+        mThumbPaint = new Paint();
+        mThumbPaint.setAntiAlias(true);
+        mThumbPaint.setColor(Themes.getColorAccent(context));
+        mThumbPaint.setStyle(Paint.Style.FILL);
+
+        Resources res = getResources();
+        mWidth = mMinWidth = res.getDimensionPixelSize(R.dimen.fastscroll_track_min_width);
+        mMaxWidth = res.getDimensionPixelSize(R.dimen.fastscroll_track_max_width);
+
+        mThumbPadding = res.getDimensionPixelSize(R.dimen.fastscroll_thumb_padding);
+        mThumbHeight = res.getDimensionPixelSize(R.dimen.fastscroll_thumb_height);
+
+        mConfig = ViewConfiguration.get(context);
+        mDeltaThreshold = res.getDisplayMetrics().density * SCROLL_DELTA_THRESHOLD_DP;
+
+        TypedArray ta =
+                context.obtainStyledAttributes(attrs, R.styleable.RecyclerViewFastScroller, defStyleAttr, 0);
+        mCanThumbDetach = ta.getBoolean(R.styleable.RecyclerViewFastScroller_canThumbDetach, false);
+        ta.recycle();
+    }
+
+    public void setRecyclerView(BaseRecyclerView rv, TextView popupView) {
+        mRv = rv;
+        mRv.addOnScrollListener(new RecyclerView.OnScrollListener() {
+            @Override
+            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+                mDy = dy;
+
+                // TODO(winsonc): If we want to animate the section heads while scrolling, we can
+                //                initiate that here if the recycler view scroll state is not
+                //                RecyclerView.SCROLL_STATE_IDLE.
+
+                mRv.onUpdateScrollbar(dy);
+            }
+        });
+
+        mPopupView = popupView;
+        mPopupView.setBackground(
+                new FastScrollThumbDrawable(mThumbPaint, Utilities.isRtl(getResources())));
+    }
+
+    public void reattachThumbToScroll() {
+        mIsThumbDetached = false;
+    }
+
+    public void setThumbOffsetY(int y) {
+        if (mThumbOffsetY == y) {
+            return;
+        }
+        mThumbOffsetY = y;
+        invalidate();
+    }
+
+    public int getThumbOffsetY() {
+        return mThumbOffsetY;
+    }
+
+    private void setTrackWidth(int width) {
+        if (mWidth == width) {
+            return;
+        }
+        mWidth = width;
+        invalidate();
+    }
+
+    public int getThumbHeight() {
+        return mThumbHeight;
+    }
+
+    public boolean isDraggingThumb() {
+        return mIsDragging;
+    }
+
+    public boolean isThumbDetached() {
+        return mIsThumbDetached;
+    }
+
+    /**
+     * Handles the touch event and determines whether to show the fast scroller (or updates it if
+     * it is already showing).
+     */
+    public boolean handleTouchEvent(MotionEvent ev) {
+        int x = (int) ev.getX();
+        int y = (int) ev.getY();
+        switch (ev.getAction()) {
+            case MotionEvent.ACTION_DOWN:
+                // Keep track of the down positions
+                mDownX = x;
+                mDownY = mLastY = y;
+
+                if ((Math.abs(mDy) < mDeltaThreshold &&
+                        mRv.getScrollState() != RecyclerView.SCROLL_STATE_IDLE)) {
+                    // now the touch events are being passed to the {@link WidgetCell} until the
+                    // touch sequence goes over the touch slop.
+                    mRv.stopScroll();
+                }
+                if (isNearThumb(x, y)) {
+                    mTouchOffsetY = mDownY - mThumbOffsetY;
+                } else if (FeatureFlags.LAUNCHER3_DIRECT_SCROLL
+                        && mRv.supportsFastScrolling()
+                        && isNearScrollBar(mDownX)) {
+                    calcTouchOffsetAndPrepToFastScroll(mDownY, mLastY);
+                    updateFastScrollSectionNameAndThumbOffset(mLastY, y);
+                }
+                break;
+            case MotionEvent.ACTION_MOVE:
+                mLastY = y;
+
+                // Check if we should start scrolling, but ignore this fastscroll gesture if we have
+                // exceeded some fixed movement
+                mIgnoreDragGesture |= Math.abs(y - mDownY) > mConfig.getScaledPagingTouchSlop();
+                if (!mIsDragging && !mIgnoreDragGesture && mRv.supportsFastScrolling() &&
+                        isNearThumb(mDownX, mLastY) &&
+                        Math.abs(y - mDownY) > mConfig.getScaledTouchSlop()) {
+                    calcTouchOffsetAndPrepToFastScroll(mDownY, mLastY);
+                }
+                if (mIsDragging) {
+                    updateFastScrollSectionNameAndThumbOffset(mLastY, y);
+                }
+                break;
+            case MotionEvent.ACTION_UP:
+            case MotionEvent.ACTION_CANCEL:
+                mRv.onFastScrollCompleted();
+                mTouchOffsetY = 0;
+                mLastTouchY = 0;
+                mIgnoreDragGesture = false;
+                if (mIsDragging) {
+                    mIsDragging = false;
+                    animatePopupVisibility(false);
+                    showActiveScrollbar(false);
+                }
+                break;
+        }
+        return mIsDragging;
+    }
+
+    private void calcTouchOffsetAndPrepToFastScroll(int downY, int lastY) {
+        mRv.getParent().requestDisallowInterceptTouchEvent(true);
+        mIsDragging = true;
+        if (mCanThumbDetach) {
+            mIsThumbDetached = true;
+        }
+        mTouchOffsetY += (lastY - downY);
+        animatePopupVisibility(true);
+        showActiveScrollbar(true);
+    }
+
+    private void updateFastScrollSectionNameAndThumbOffset(int lastY, int y) {
+        // Update the fastscroller section name at this touch position
+        int bottom = mRv.getScrollbarTrackHeight() - mThumbHeight;
+        float boundedY = (float) Math.max(0, Math.min(bottom, y - mTouchOffsetY));
+        String sectionName = mRv.scrollToPositionAtProgress(boundedY / bottom);
+        if (!sectionName.equals(mPopupSectionName)) {
+            mPopupSectionName = sectionName;
+            mPopupView.setText(sectionName);
+        }
+        animatePopupVisibility(!sectionName.isEmpty());
+        updatePopupY(lastY);
+        mLastTouchY = boundedY;
+        setThumbOffsetY((int) mLastTouchY);
+    }
+
+    public void onDraw(Canvas canvas) {
+        if (mThumbOffsetY < 0) {
+            return;
+        }
+        int saveCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
+        canvas.translate(getWidth() / 2, mRv.getPaddingTop());
+        // Draw the track
+        float halfW = mWidth / 2;
+        canvas.drawRoundRect(-halfW, 0, halfW, mRv.getScrollbarTrackHeight(),
+                mWidth, mWidth, mTrackPaint);
+
+        canvas.translate(0, mThumbOffsetY);
+        halfW += mThumbPadding;
+        float r = mWidth + mThumbPadding + mThumbPadding;
+        canvas.drawRoundRect(-halfW, 0, halfW, mThumbHeight, r, r, mThumbPaint);
+        canvas.restoreToCount(saveCount);
+    }
+
+
+    /**
+     * Animates the width of the scrollbar.
+     */
+    private void showActiveScrollbar(boolean isScrolling) {
+        if (mWidthAnimator != null) {
+            mWidthAnimator.cancel();
+        }
+
+        mWidthAnimator = ObjectAnimator.ofInt(this, TRACK_WIDTH,
+                isScrolling ? mMaxWidth : mMinWidth);
+        mWidthAnimator.setDuration(SCROLL_BAR_VIS_DURATION);
+        mWidthAnimator.start();
+    }
+
+    /**
+     * Returns whether the specified point is inside the thumb bounds.
+     */
+    private boolean isNearThumb(int x, int y) {
+        int offset = y - mRv.getPaddingTop() - mThumbOffsetY;
+
+        return x >= 0 && x < getWidth() && offset >= 0 && offset <= mThumbHeight;
+    }
+
+    /**
+     * Returns true if AllAppsTransitionController can handle vertical motion
+     * beginning at this point.
+     */
+    public boolean shouldBlockIntercept(int x, int y) {
+        return isNearThumb(x, y);
+    }
+
+    /**
+     * Returns whether the specified x position is near the scroll bar.
+     */
+    public boolean isNearScrollBar(int x) {
+        return x >= (getWidth() - mMaxWidth) / 2 && x <= (getWidth() + mMaxWidth) / 2;
+    }
+
+    private void animatePopupVisibility(boolean visible) {
+        if (mPopupVisible != visible) {
+            mPopupVisible = visible;
+            mPopupView.animate().cancel();
+            mPopupView.animate().alpha(visible ? 1f : 0f).setDuration(visible ? 200 : 150).start();
+        }
+    }
+
+    private void updatePopupY(int lastTouchY) {
+        int height = mPopupView.getHeight();
+        float top = lastTouchY - (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * height)
+                + mRv.getPaddingTop();
+        top = Utilities.boundToRange(top,
+                mMaxWidth, mRv.getScrollbarTrackHeight() - mMaxWidth - height);
+        mPopupView.setTranslationY(top);
+    }
+}