1/*
2 * Copyright (C) 2011 Google Inc.
3 * Licensed to The Android Open Source Project.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18package com.android.mail.browse;
19
20import android.content.Context;
21import android.util.AttributeSet;
22import android.view.View;
23
24import com.android.mail.browse.ScrollNotifier.ScrollListener;
25
26/**
27 * An overlay to sit on top of WebView, message headers, and snap header to display scrollbars.
28 * It has to sit on top of all other views that compose the conversation so that the scrollbars are
29 * not obscured.
30 *
31 */
32public class ScrollIndicatorsView extends View implements ScrollListener {
33
34    private ScrollNotifier mSource;
35
36    public ScrollIndicatorsView(Context context) {
37        super(context);
38    }
39
40    public ScrollIndicatorsView(Context context, AttributeSet attrs) {
41        super(context, attrs);
42    }
43
44    public void setSourceView(ScrollNotifier notifier) {
45        mSource = notifier;
46        mSource.addScrollListener(this);
47    }
48
49    @Override
50    protected int computeVerticalScrollRange() {
51        return mSource.computeVerticalScrollRange();
52    }
53
54    @Override
55    protected int computeVerticalScrollOffset() {
56        return mSource.computeVerticalScrollOffset();
57    }
58
59    @Override
60    protected int computeVerticalScrollExtent() {
61        return mSource.computeVerticalScrollExtent();
62    }
63
64    @Override
65    protected int computeHorizontalScrollRange() {
66        return mSource.computeHorizontalScrollRange();
67    }
68
69    @Override
70    protected int computeHorizontalScrollOffset() {
71        return mSource.computeHorizontalScrollOffset();
72    }
73
74    @Override
75    protected int computeHorizontalScrollExtent() {
76        return mSource.computeHorizontalScrollExtent();
77    }
78
79    @Override
80    public void onNotifierScroll(int top) {
81        awakenScrollBars();
82    }
83}
84