1/*
2 * Copyright (C) 2014 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.printspooler.widget;
18
19import android.content.Context;
20import android.content.res.TypedArray;
21import android.util.AttributeSet;
22import android.view.View;
23import android.view.ViewGroup;
24import com.android.printspooler.R;
25
26/**
27 * This class is a layout manager for the print options. The options are
28 * arranged in a configurable number of columns and enough rows to fit all
29 * the options given the column count.
30 */
31@SuppressWarnings("unused")
32public final class PrintOptionsLayout extends ViewGroup {
33
34    private int mColumnCount;
35
36    public PrintOptionsLayout(Context context, AttributeSet attrs) {
37        super(context, attrs);
38
39        TypedArray typedArray = context.obtainStyledAttributes(attrs,
40                R.styleable.PrintOptionsLayout);
41        mColumnCount = typedArray.getInteger(R.styleable.PrintOptionsLayout_columnCount, 0);
42        typedArray.recycle();
43    }
44
45    public void setColumnCount(int columnCount) {
46        if (mColumnCount != columnCount) {
47            mColumnCount = columnCount;
48            requestLayout();
49        }
50    }
51
52    @Override
53    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
54        final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
55        final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
56
57        final int columnWidth = (widthSize != 0)
58                ? (widthSize - mPaddingLeft - mPaddingRight) / mColumnCount : 0;
59
60        int width = 0;
61        int height = 0;
62        int childState = 0;
63
64        final int childCount = getChildCount();
65        final int rowCount = childCount / mColumnCount + childCount % mColumnCount;
66
67        for (int row = 0; row < rowCount; row++) {
68            int rowWidth = 0;
69            int rowHeight = 0;
70
71            for (int col = 0; col < mColumnCount; col++) {
72                final int childIndex = row * mColumnCount + col;
73
74                if (childIndex >= childCount) {
75                    break;
76                }
77
78                View child = getChildAt(childIndex);
79
80                if (child.getVisibility() == GONE) {
81                    continue;
82                }
83
84                MarginLayoutParams childParams = (MarginLayoutParams) child.getLayoutParams();
85
86                final int childWidthMeasureSpec;
87                if (columnWidth > 0) {
88                    childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
89                            columnWidth - childParams.getMarginStart() - childParams.getMarginEnd(),
90                            MeasureSpec.EXACTLY);
91                } else {
92                    childWidthMeasureSpec = getChildMeasureSpec(widthMeasureSpec,
93                            getPaddingStart() + getPaddingEnd() + width, childParams.width);
94                }
95
96                final int childHeightMeasureSpec = getChildMeasureSpec(heightMeasureSpec,
97                        getPaddingTop() + getPaddingBottom() + height, childParams.height);
98
99                child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
100
101                childState = combineMeasuredStates(childState, child.getMeasuredState());
102
103                rowWidth += child.getMeasuredWidth() + childParams.getMarginStart()
104                        + childParams.getMarginEnd();
105
106                rowHeight = Math.max(rowHeight, child.getMeasuredHeight() + childParams.topMargin
107                        + childParams.bottomMargin);
108            }
109
110            width = Math.max(width, rowWidth);
111            height += rowHeight;
112        }
113
114        width += getPaddingStart() + getPaddingEnd();
115        width = Math.max(width, getMinimumWidth());
116
117        height += getPaddingTop() + getPaddingBottom();
118        height = Math.max(height, getMinimumHeight());
119
120        setMeasuredDimension(resolveSizeAndState(width, widthMeasureSpec, childState),
121                resolveSizeAndState(height, heightMeasureSpec,
122                        childState << MEASURED_HEIGHT_STATE_SHIFT));
123    }
124
125    @Override
126    protected void onLayout(boolean changed, int l, int t, int r, int b) {
127        final int childCount = getChildCount();
128        final int rowCount = childCount / mColumnCount + childCount % mColumnCount;
129
130        int cellStart = getPaddingStart();
131        int cellTop = getPaddingTop();
132
133        for (int row = 0; row < rowCount; row++) {
134            int rowHeight = 0;
135
136            for (int col = 0; col < mColumnCount; col++) {
137                final int childIndex = row * mColumnCount + col;
138
139                if (childIndex >= childCount) {
140                    break;
141                }
142
143                View child = getChildAt(childIndex);
144
145                if (child.getVisibility() == GONE) {
146                    continue;
147                }
148
149                MarginLayoutParams childParams = (MarginLayoutParams) child.getLayoutParams();
150
151                final int childLeft = cellStart + childParams.getMarginStart();
152                final int childTop = cellTop + childParams.topMargin;
153                final int childRight = childLeft + child.getMeasuredWidth();
154                final int childBottom = childTop + child.getMeasuredHeight();
155
156                child.layout(childLeft, childTop, childRight, childBottom);
157
158                cellStart = childRight + childParams.getMarginEnd();
159
160                rowHeight = Math.max(rowHeight, child.getMeasuredHeight()
161                        + childParams.topMargin + childParams.bottomMargin);
162            }
163
164            cellStart = getPaddingStart();
165            cellTop += rowHeight;
166        }
167    }
168
169    @Override
170    public LayoutParams generateLayoutParams(AttributeSet attrs) {
171        return new ViewGroup.MarginLayoutParams(getContext(), attrs);
172    }
173}
174