ControlBar.java revision aa93f6777233b789feb14d95d900b158d0ac4841 
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    private int mChildMarginFromCenter;
25
26    public ControlBar(Context context, AttributeSet attrs) {
27        super(context, attrs);
28    }
29
30    public ControlBar(Context context, AttributeSet attrs, int defStyle) {
31        super(context, attrs, defStyle);
32    }
33
34    @Override
35    public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
36        if (getChildCount() > 0) {
37            if (getChildAt(getChildCount() / 2).requestFocus(direction, previouslyFocusedRect)) {
38                return true;
39            }
40        }
41        return super.requestFocus(direction, previouslyFocusedRect);
42    }
43
44    public void setChildMarginFromCenter(int marginFromCenter) {
45        mChildMarginFromCenter = marginFromCenter;
46    }
47
48    @Override
49    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
50        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
51        if (mChildMarginFromCenter <= 0) {
52            return;
53        }
54
55        int totalExtraMargin = 0;
56        for (int i = 0; i < getChildCount() - 1; i++) {
57            View first = getChildAt(i);
58            View second = getChildAt(i+1);
59            int measuredWidth = first.getMeasuredWidth() + second.getMeasuredWidth();
60            int marginStart = mChildMarginFromCenter - measuredWidth / 2;
61            LayoutParams lp = (LayoutParams) second.getLayoutParams();
62            int extraMargin = marginStart - lp.getMarginStart();
63            lp.setMarginStart(marginStart);
64            second.setLayoutParams(lp);
65            totalExtraMargin += extraMargin;
66        }
67        setMeasuredDimension(getMeasuredWidth() + totalExtraMargin, getMeasuredHeight());
68    }
69}
70