Merging search bar with all apps

Change-Id: I78577124cd3c05d52669c3e52b0294d6eb1d194d

1 files changed, 101 insertions, 0 deletions

diff --git a/src/com/android/launcher3/allapps/HeaderElevationController.java b/src/com/android/launcher3/allapps/HeaderElevationController.java
new file mode 100644
index 000000000..07f583caa
--- /dev/null
+++ b/src/com/android/launcher3/allapps/HeaderElevationController.java
@@ -0,0 +1,101 @@
+package com.android.launcher3.allapps;
+
+import android.annotation.TargetApi;
+import android.content.res.Resources;
+import android.graphics.Rect;
+import android.graphics.drawable.GradientDrawable;
+import android.os.Build;
+import android.support.v7.widget.RecyclerView;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewOutlineProvider;
+import android.widget.FrameLayout;
+
+import com.android.launcher3.R;
+
+/**
+ * Helper class for controlling the header elevation in response to RecyclerView scroll.
+ */
+public abstract class HeaderElevationController extends RecyclerView.OnScrollListener {
+
+    private int mCurrentY = 0;
+
+    public void reset() {
+        mCurrentY = 0;
+        onScroll(mCurrentY);
+    }
+
+    @Override
+    public final void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        mCurrentY += dy;
+        onScroll(mCurrentY);
+    }
+
+    public void updateBackgroundPadding(Rect bgPadding) { }
+
+    abstract void onScroll(int scrollY);
+
+    public static class ControllerV16 extends HeaderElevationController {
+
+        private final View mShadow;
+        private final float mScrollToElevation;
+
+        public ControllerV16(View header) {
+            Resources res = header.getContext().getResources();
+            mScrollToElevation = res.getDimension(R.dimen.all_apps_header_scroll_to_elevation);
+
+            mShadow = new View(header.getContext());
+            mShadow.setBackground(new GradientDrawable(
+                    GradientDrawable.Orientation.TOP_BOTTOM, new int[] {0x1E000000, 0x00000000}));
+            mShadow.setAlpha(0);
+
+            FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
+                    FrameLayout.LayoutParams.MATCH_PARENT,
+                    res.getDimensionPixelSize(R.dimen.all_apps_header_shadow_height));
+            lp.topMargin = ((FrameLayout.LayoutParams) header.getLayoutParams()).height;
+
+            ((ViewGroup) header.getParent()).addView(mShadow, lp);
+        }
+
+        @Override
+        public void onScroll(int scrollY) {
+            float elevationPct = (float) Math.min(scrollY, mScrollToElevation) /
+                    mScrollToElevation;
+            mShadow.setAlpha(elevationPct);
+        }
+
+        @Override
+        public void updateBackgroundPadding(Rect bgPadding) {
+            FrameLayout.LayoutParams lp = (FrameLayout.LayoutParams) mShadow.getLayoutParams();
+            lp.leftMargin = bgPadding.left;
+            lp.rightMargin = bgPadding.right;
+            mShadow.requestLayout();
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    public static class ControllerVL extends HeaderElevationController {
+
+        private final View mHeader;
+        private final float mMaxElevation;
+        private final float mScrollToElevation;
+
+        public ControllerVL(View header) {
+            mHeader = header;
+            mHeader.setOutlineProvider(ViewOutlineProvider.BOUNDS);
+
+            Resources res = header.getContext().getResources();
+            mMaxElevation = res.getDimension(R.dimen.all_apps_header_max_elevation);
+            mScrollToElevation = res.getDimension(R.dimen.all_apps_header_scroll_to_elevation);
+        }
+
+        @Override
+        public void onScroll(int scrollY) {
+            float elevationPct = Math.min(scrollY, mScrollToElevation) / mScrollToElevation;
+            float newElevation = mMaxElevation * elevationPct;
+            if (Float.compare(mHeader.getElevation(), newElevation) != 0) {
+                mHeader.setElevation(newElevation);
+            }
+        }
+    }
+}