1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.internal.widget;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;
import android.widget.LinearLayout;
import com.android.internal.R;
/**
* An extension of LinearLayout that automatically switches to vertical
* orientation when it can't fit its child views horizontally.
*/
public class ButtonBarLayout extends LinearLayout {
/** Whether the current configuration allows stacking. */
private final boolean mAllowStacking;
/** Whether the layout is currently stacked. */
private boolean mStacked;
private int mLastWidthSize = -1;
public ButtonBarLayout(Context context, AttributeSet attrs) {
super(context, attrs);
final TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ButtonBarLayout);
mAllowStacking = ta.getBoolean(R.styleable.ButtonBarLayout_allowStacking, false);
ta.recycle();
mStacked = getOrientation() == VERTICAL;
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mAllowStacking) {
final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
if (widthSize > mLastWidthSize && mStacked) {
// We're being measured wider this time, try un-stacking.
setStacked(false);
}
mLastWidthSize = widthSize;
}
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (mAllowStacking && !mStacked) {
final int measuredWidth = getMeasuredWidthAndState();
final int measuredWidthState = measuredWidth & MEASURED_STATE_MASK;
if (measuredWidthState == MEASURED_STATE_TOO_SMALL) {
setStacked(true);
// Measure again in the new orientation.
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
}
private void setStacked(boolean stacked) {
setOrientation(stacked ? LinearLayout.VERTICAL : LinearLayout.HORIZONTAL);
setGravity(stacked ? Gravity.RIGHT : Gravity.BOTTOM);
final View spacer = findViewById(R.id.spacer);
if (spacer != null) {
spacer.setVisibility(stacked ? View.GONE : View.INVISIBLE);
}
// Reverse the child order. This is specific to the Material button
// bar's layout XML and will probably not generalize.
final int childCount = getChildCount();
for (int i = childCount - 2; i >= 0; i--) {
bringChildToFront(getChildAt(i));
}
mStacked = stacked;
}
}
|
