Enable work profile tab in all apps.

This CL will bring two tabs to all apps: Personal and Work,
currently only if the user has a workfile set up and
behind a feature flag defaulting to disabled.

Bug: 68713881

Change-Id: Ib5a558281ef3593359db3ad593ee1d0cf279f547

src/com/android/launcher3/allapps/FloatingHeaderHandler.java

@@ -0,0 +1,139 @@
+/*
+ * 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.allapps;
+
+import android.graphics.Rect;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.v7.widget.RecyclerView;
+import android.view.View;
+
+import com.android.launcher3.R;
+
+public class FloatingHeaderHandler extends RecyclerView.OnScrollListener {
+
+    private final int mMaxTranslation;
+    private final View mHeaderView;
+    private final PredictionRowView mContentView;
+    private final RecyclerView mMainRV;
+    private final RecyclerView mWorkRV;
+    private final Rect mClip = new Rect(0, 0, Integer.MAX_VALUE, Integer.MAX_VALUE);
+
+    private boolean mHeaderHidden;
+    private int mSnappedScrolledY;
+    private int mTranslationY;
+    private int mMainScrolledY;
+    private int mWorkScrolledY;
+    private boolean mMainRVActive;
+
+    public FloatingHeaderHandler(@NonNull View header, @NonNull RecyclerView personalRV,
+            @Nullable RecyclerView workRV, int contentHeight) {
+        mHeaderView = header;
+        mContentView = mHeaderView.findViewById(R.id.header_content);
+        mContentView.getLayoutParams().height = contentHeight;
+        mMaxTranslation = contentHeight;
+        mMainRV = personalRV;
+        mMainRV.addOnScrollListener(this);
+        mWorkRV = workRV;
+        if (workRV != null) {
+            workRV.addOnScrollListener(this);
+        }
+        setMainActive(true);
+    }
+
+    public void setMainActive(boolean active) {
+        mMainRVActive = active;
+        mSnappedScrolledY = getCurrentScroll() - mMaxTranslation;
+        setExpanded(true);
+    }
+
+    public View getHeaderView() {
+        return mHeaderView;
+    }
+
+    public PredictionRowView getContentView() {
+        return mContentView;
+    }
+
+    @Override
+    public void onScrolled(RecyclerView rv, int dx, int dy) {
+        boolean isMainRV = rv == mMainRV;
+        if (isMainRV != mMainRVActive) {
+            return;
+        }
+
+        int current = isMainRV
+                ? (mMainScrolledY -= dy)
+                : (mWorkScrolledY -= dy);
+
+        if (dy == 0) {
+            setExpanded(true);
+        } else {
+            moved(current);
+            apply();
+        }
+    }
+
+    private void moved(final int currentScrollY) {
+        if (mHeaderHidden) {
+            if (currentScrollY <= mSnappedScrolledY) {
+                mSnappedScrolledY = currentScrollY;
+            } else {
+                mHeaderHidden = false;
+            }
+            mTranslationY = currentScrollY;
+        } else {
+            mTranslationY = currentScrollY - mSnappedScrolledY - mMaxTranslation;
+
+            // update state vars
+            if (mTranslationY >= 0) { // expanded: must not move down further
+                mTranslationY = 0;
+                mSnappedScrolledY = currentScrollY - mMaxTranslation;
+            } else if (mTranslationY <= -mMaxTranslation) { // hide or stay hidden
+                mHeaderHidden = true;
+                mSnappedScrolledY = currentScrollY;
+            }
+        }
+    }
+
+    private void apply() {
+        mTranslationY = Math.max(mTranslationY, -mMaxTranslation);
+        mHeaderView.setTranslationY(mTranslationY);
+        mClip.top = mMaxTranslation + mTranslationY;
+        mMainRV.setClipBounds(mClip);
+        if (mWorkRV != null) {
+            mWorkRV.setClipBounds(mClip);
+        }
+    }
+
+    private void setExpanded(boolean expand) {
+        int translateTo = expand ? 0 : -mMaxTranslation;
+        mTranslationY = translateTo;
+        apply();
+
+        mHeaderHidden = !expand;
+        mSnappedScrolledY = expand ? getCurrentScroll() - mMaxTranslation : getCurrentScroll();
+    }
+
+    public boolean isExpanded() {
+        return !mHeaderHidden;
+    }
+
+    private int getCurrentScroll() {
+        return mMainRVActive ? mMainScrolledY : mWorkScrolledY;
+    }
+
+}