ColumnUtils.java

/*
 * Copyright (c) 1998-2017 by Richard A. Wilkes. All rights reserved.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, version 2.0. If a copy of the MPL was not distributed with
 * this file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This Source Code Form is "Incompatible With Secondary Licenses", as
 * defined by the Mozilla Public License, version 2.0.
 */

package com.trollworks.gcs.widgets.outline;

import com.trollworks.toolkit.ui.widget.outline.Column;
import com.trollworks.toolkit.ui.widget.outline.Outline;
import com.trollworks.toolkit.ui.widget.outline.OutlineModel;

import java.util.ArrayList;

/** Utilities for columns. */
public class ColumnUtils {
	/**
	 * Packs the columns to their preferred sizes.
	 *
	 * @param outline The {@link Outline} to pack.
	 * @param width The width available for all columns.
	 */
	public static void pack(Outline outline, int width) {
		OutlineModel outlineModel = outline.getModel();
		int count = outlineModel.getColumnCount();
		ArrayList<Column> changed = new ArrayList<>();
		int[] widths = new int[count];
		Column column;
		if (outline.shouldDrawColumnDividers()) {
			width -= count - 1;
		}
		for (int i = 0; i < count; i++) {
			column = outlineModel.getColumnAtIndex(i);
			widths[i] = column.getPreferredWidth(outline);
			width -= widths[i];
		}
		if (width >= 0) {
			if (width > 0) {
				for (int i = 0; i < count; i++) {
					column = outlineModel.getColumnAtIndex(i);
					if (outlineModel.isHierarchyColumn(column)) {
						widths[i] += width;
						width = 0;
						break;
					}
				}
				if (width > 0) {
					widths[0] += width;
				}
			}
		} else {
			int pos = 0;
			int[] list = new int[count];
			int[] minList = new int[count];
			for (int i = 0; i < count; i++) {
				column = outlineModel.getColumnAtIndex(i);
				if (column.getRowCell(null).participatesInDynamicRowLayout()) {
					int min = column.getPreferredHeaderWidth(outline);

					if (min < widths[i]) {
						list[pos] = i;
						minList[pos++] = min;
					}
				}
			}
			int[] list2 = new int[count];
			int[] minList2 = new int[count];
			int pos2 = 0;
			while (width < 0 && pos > 0) {
				int amt;
				if (-width > pos) {
					amt = width / pos;
				} else {
					amt = -1;
				}
				for (int i = 0; i < pos && width < 0; i++) {
					int which = list[i];
					int minWidth = minList[i];

					widths[which] += amt;
					width -= amt;
					if (widths[which] < minWidth) {
						width -= minWidth - widths[which];
						widths[which] = minWidth;
					} else if (widths[which] > minWidth) {
						list2[pos2] = which;
						minList2[pos2++] = minWidth;
					}
				}
				int[] swap = list;
				list = list2;
				list2 = swap;
				swap = minList;
				minList = minList2;
				minList2 = swap;
				pos = pos2;
				pos2 = 0;
			}
		}
		for (int i = 0; i < count; i++) {
			column = outlineModel.getColumnAtIndex(i);
			if (widths[i] != column.getWidth()) {
				column.setWidth(outline, widths[i]);
				changed.add(column);
			}
		}
		outline.updateRowHeightsIfNeeded(changed);
	}
}