Make RecyclerView smooth scroll speed customizable

app/src/main/java/com/hippo/widget/recyclerview/SimpleSmoothScroller.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2015 Hippo Seven
+ *
+ * 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
+ * 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.hippo.widget.recyclerview;
+
+import android.content.Context;
+import android.support.v7.widget.LinearSmoothScroller;
+
+public abstract class SimpleSmoothScroller extends LinearSmoothScroller {
+
+    private float mMillisecondsPerPx;
+
+    public SimpleSmoothScroller(Context context, float millisecondsPerInch) {
+        super(context);
+        mMillisecondsPerPx = millisecondsPerInch / context.getResources().getDisplayMetrics().densityDpi;
+    }
+
+    @Override
+    protected int calculateTimeForScrolling(int dx) {
+        if (mMillisecondsPerPx <= 0) {
+            return super.calculateTimeForScrolling(dx);
+        } else {
+            return (int) Math.ceil(Math.abs(dx) * mMillisecondsPerPx);
+        }
+    }
+}