TimelineRow.java revision 95961816a768da387f0b5523cf4363ace2044089 
1/*
2 * Copyright (C) 2015 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.tv.guide;
18
19import android.content.Context;
20import android.util.AttributeSet;
21
22public class TimelineRow extends TimelineGridView {
23    private static final float FADING_EDGE_STRENGTH_START = 1.0f;
24
25    private int mScrollPosition;
26
27    public TimelineRow(Context context) {
28        this(context, null);
29    }
30
31    public TimelineRow(Context context, AttributeSet attrs) {
32        this(context, attrs, 0);
33    }
34
35    public TimelineRow(Context context, AttributeSet attrs, int defStyle) {
36        super(context, attrs, defStyle);
37    }
38
39    public void resetScroll() {
40        getLayoutManager().scrollToPosition(0);
41    }
42
43    /** Returns the current scroll position */
44    public int getScrollOffset() {
45        return Math.abs(mScrollPosition);
46    }
47
48    /** Scrolls horizontally to the given position. */
49    public void scrollTo(int scrollOffset, boolean smoothScroll) {
50        int dx =
51                (scrollOffset - getScrollOffset())
52                        * (getLayoutDirection() == LAYOUT_DIRECTION_LTR ? 1 : -1);
53        if (smoothScroll) {
54            smoothScrollBy(dx, 0);
55        } else {
56            scrollBy(dx, 0);
57        }
58    }
59
60    @Override
61    public void onRtlPropertiesChanged(int layoutDirection) {
62        super.onRtlPropertiesChanged(layoutDirection);
63        // Reset scroll
64        if (isAttachedToWindow()) {
65            scrollTo(getScrollOffset(), false);
66        }
67    }
68
69    @Override
70    public void onScrolled(int dx, int dy) {
71        if (dx == 0 && dy == 0) {
72            mScrollPosition = 0;
73        } else {
74            mScrollPosition += dx;
75        }
76    }
77
78    @Override
79    protected float getLeftFadingEdgeStrength() {
80        return (getLayoutDirection() == LAYOUT_DIRECTION_LTR) ? FADING_EDGE_STRENGTH_START : 0;
81    }
82
83    @Override
84    protected float getRightFadingEdgeStrength() {
85        return (getLayoutDirection() == LAYOUT_DIRECTION_RTL) ? FADING_EDGE_STRENGTH_START : 0;
86    }
87}
88