diff --git a/app/src/main/java/com/hippo/widget/IndicatingScrollView.java b/app/src/main/java/com/hippo/widget/IndicatingScrollView.java
new file mode 100644
index 000000000..e02a89871
--- /dev/null
+++ b/app/src/main/java/com/hippo/widget/IndicatingScrollView.java
@@ -0,0 +1,92 @@
+/*
+ * 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
+ * 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.hippo.widget;
+
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.support.annotation.NonNull;
+import android.util.AttributeSet;
+import android.widget.ScrollView;
+
+import com.hippo.ehviewer.R;
+
+public class IndicatingScrollView extends ScrollView {
+
+ private int mIndicatorHeight;
+
+ private final Paint mPaint = new Paint();
+ private final Rect mTemp = new Rect();
+
+ public IndicatingScrollView(Context context, AttributeSet attrs) {
+ super(context, attrs);
+ init(context, attrs);
+ }
+
+ public IndicatingScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
+ super(context, attrs, defStyleAttr);
+ init(context, attrs);
+ }
+
+ private void init(Context context, AttributeSet attrs) {
+ TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.IndicatingScrollView);
+ mIndicatorHeight = a.getDimensionPixelOffset(R.styleable.IndicatingScrollView_indicatorHeight, 1);
+ mPaint.setColor(a.getColor(R.styleable.IndicatingScrollView_indicatorColor, Color.BLACK));
+ mPaint.setStyle(Paint.Style.FILL);
+ a.recycle();
+ }
+
+ private void fillTopIndicatorDrawRect() {
+ mTemp.set(0, 0, getWidth(), mIndicatorHeight);
+ }
+
+ private void fillBottomIndicatorDrawRect() {
+ mTemp.set(0, getHeight() - mIndicatorHeight, getWidth(), getHeight());
+ }
+
+ private boolean needShowTopIndicator() {
+ return canScrollVertically(-1);
+ }
+
+ private boolean needShowBottomIndicator() {
+ return canScrollVertically(1);
+ }
+
+ @Override
+ public void draw(@NonNull Canvas canvas) {
+ super.draw(canvas);
+
+ final int restoreCount = canvas.save();
+ canvas.translate(getScrollX(), getScrollY());
+
+ // Draw top indicator
+ if (needShowTopIndicator()) {
+ fillTopIndicatorDrawRect();
+ canvas.drawRect(mTemp, mPaint);
+ }
+ // Draw bottom indicator
+ if (needShowBottomIndicator()) {
+ fillBottomIndicatorDrawRect();
+ canvas.drawRect(mTemp, mPaint);
+ }
+
+ canvas.restoreToCount(restoreCount);
+ }
+}
diff --git a/app/src/main/res/values/attrs.xml b/app/src/main/res/values/attrs.xml
index 5ce22a13c..8f8756db2 100644
--- a/app/src/main/res/values/attrs.xml
+++ b/app/src/main/res/values/attrs.xml
@@ -113,4 +113,9 @@
+
+
+
+
+
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 085dceb63..456c636b5 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -120,4 +120,13 @@
- true
+
+
+
+