1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.internal.widget;
18
19public class ScrollBarUtils {
20
21    public static int getThumbLength(int size, int thickness, int extent, int range) {
22        // Avoid the tiny thumb.
23        final int minLength = thickness * 2;
24        int length = Math.round((float) size * extent / range);
25        if (length < minLength) {
26            length = minLength;
27        }
28        return length;
29    }
30
31    public static int getThumbOffset(int size, int thumbLength, int extent, int range, int offset) {
32        // Avoid the too-big thumb.
33        int thumbOffset = Math.round((float) (size - thumbLength) * offset / (range - extent));
34        if (thumbOffset > size - thumbLength) {
35            thumbOffset = size - thumbLength;
36        }
37        return thumbOffset;
38    }
39}
40