1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5 * in compliance with the License. You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software distributed under the License
10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11 * or implied. See the License for the specific language governing permissions and limitations under
12 * the License.
13 */
14package android.support.v17.leanback.widget;
15
16import android.content.Context;
17import android.graphics.Rect;
18import android.util.AttributeSet;
19import android.view.View;
20import android.widget.LinearLayout;
21
22class ControlBar extends LinearLayout {
23
24    public interface OnChildFocusedListener {
25        public void onChildFocusedListener(View child, View focused);
26    }
27
28    private int mChildMarginFromCenter;
29    private OnChildFocusedListener mOnChildFocusedListener;
30
31    public ControlBar(Context context, AttributeSet attrs) {
32        super(context, attrs);
33    }
34
35    public ControlBar(Context context, AttributeSet attrs, int defStyle) {
36        super(context, attrs, defStyle);
37    }
38
39    @Override
40    public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
41        if (getChildCount() > 0) {
42            if (getChildAt(getChildCount() / 2).requestFocus(direction, previouslyFocusedRect)) {
43                return true;
44            }
45        }
46        return super.requestFocus(direction, previouslyFocusedRect);
47    }
48
49    public void setOnChildFocusedListener(OnChildFocusedListener listener) {
50        mOnChildFocusedListener = listener;
51    }
52
53    public void setChildMarginFromCenter(int marginFromCenter) {
54        mChildMarginFromCenter = marginFromCenter;
55    }
56
57    @Override
58    public void requestChildFocus (View child, View focused) {
59        super.requestChildFocus(child, focused);
60        if (mOnChildFocusedListener != null) {
61            mOnChildFocusedListener.onChildFocusedListener(child, focused);
62        }
63    }
64
65    @Override
66    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
67        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
68        if (mChildMarginFromCenter <= 0) {
69            return;
70        }
71
72        int totalExtraMargin = 0;
73        for (int i = 0; i < getChildCount() - 1; i++) {
74            View first = getChildAt(i);
75            View second = getChildAt(i+1);
76            int measuredWidth = first.getMeasuredWidth() + second.getMeasuredWidth();
77            int marginStart = mChildMarginFromCenter - measuredWidth / 2;
78            LayoutParams lp = (LayoutParams) second.getLayoutParams();
79            int extraMargin = marginStart - lp.getMarginStart();
80            lp.setMarginStart(marginStart);
81            second.setLayoutParams(lp);
82            totalExtraMargin += extraMargin;
83        }
84        setMeasuredDimension(getMeasuredWidth() + totalExtraMargin, getMeasuredHeight());
85    }
86}
87