Java example source code file (VariableGridLayout.java)

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Java - Java tags/keywords

awt, boolean, component, dimension, gui, insets, jcomponent, rectangle, suppresswarnings, swing, variablegridlayout

The VariableGridLayout.java Java example source code

/*
 * Copyright (c) 2004, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.tools.jconsole;

import java.awt.*;

import javax.swing.*;

@SuppressWarnings("serial")
public class VariableGridLayout extends GridLayout {

    private boolean fillRows, fillColumns;

    public VariableGridLayout(int rows, int cols,
                              int hgap, int vgap,
                              boolean fillRows, boolean fillColumns) {
        super(rows, cols, hgap, vgap);

        this.fillRows    = fillRows;
        this.fillColumns = fillColumns;
    }

    public void setFillRow(JComponent c, boolean b) {
        c.putClientProperty("VariableGridLayout.fillRow", b);
    }

    public void setFillColumn(JComponent c, boolean b) {
        c.putClientProperty("VariableGridLayout.fillColumn", b);
    }

    public boolean getFillRow(JComponent c) {
        Boolean b = (Boolean)c.getClientProperty("VariableGridLayout.fillRow");
        return (b != null) ? b : fillRows;
    }

    public boolean getFillColumn(JComponent c) {
        Boolean b = (Boolean)c.getClientProperty("VariableGridLayout.fillColumn");
        return (b != null) ? b : fillColumns;
    }

    public void layoutContainer(Container parent) {
        Insets insets = parent.getInsets();
        int ncomponents = parent.getComponentCount();
        int nrows = getRows();
        int ncols = getColumns();
        int hgap =  getHgap();
        int vgap =  getVgap();

        if (nrows > 0) {
            ncols = (ncomponents + nrows - 1) / nrows;
        } else {
            nrows = (ncomponents + ncols - 1) / ncols;
        }

        // Set heights
        int x;
        int y;
        int nFills = 0;
        boolean[] fills = new boolean[nrows];
        int lastFillRow = -1;
        int nComps = parent.getComponentCount();

        y = insets.top;
        for (int row = 0; row < nrows; row++) {
            // Find largest minimum height for this row
            int h = 0;
            for (int col = 0; col < ncols; col++) {
                if (row * ncols + col < nComps) {
                    Component c = parent.getComponent(row * ncols + col);
                    h = Math.max(h, c.getMinimumSize().height);
                }
            }
            // Set heights for this row
            x = insets.left;
            for (int col = 0; col < ncols; col++) {
                if (row * ncols + col < nComps) {
                    JComponent c = (JComponent)parent.getComponent(row * ncols + col);
                    int w = c.getWidth();
                    c.setBounds(x, y, w, h);
                    x += w + hgap;
                    if (col == 0 && getFillRow(c)) {
                        fills[row] = true;
                    }
                }
            }
            y += h + vgap;
            if (fills[row]) {
                nFills++;
                lastFillRow = row;
            }
        }

        // Fill heights
        if (nFills > 0 && y < parent.getHeight()) {
            // How much height to add
            int hAdd = (parent.getHeight() - y) / nFills;
            int hAdded = 0;
            for (int row = 0; row < nrows; row++) {
                if (fills[row]) {
                    if (row == lastFillRow) {
                        // Compensate for rounding error
                        hAdd = parent.getHeight() - (y+hAdded);
                    }
                    for (int col = 0; col < ncols; col++) {
                        if (row * ncols + col < nComps) {
                            Component c = parent.getComponent(row * ncols + col);
                            Rectangle b = c.getBounds();
                            c.setBounds(b.x, b.y + hAdded, b.width, b.height + hAdd);
                        }
                    }
                    hAdded += hAdd;
                }
            }
        }

        // Set widths
        nFills = 0;
        fills = new boolean[ncols];
        int lastFillCol = -1;

        x = insets.left;
        for (int col = 0; col < ncols; col++) {
            // Find largest minimum width for this column
            int w = 0;
            for (int row = 0; row < nrows; row++) {
                if (row * ncols + col < nComps) {
                    Component c = parent.getComponent(row * ncols + col);
                    w = Math.max(w, c.getMinimumSize().width);
                }
            }
            // Set widths for this column
            y = insets.top;
            for (int row = 0; row < nrows; row++) {
                if (row * ncols + col < nComps) {
                    JComponent c = (JComponent)parent.getComponent(row * ncols + col);
                    int h = c.getHeight();
                    c.setBounds(x, y, w, h);
                    y += h + vgap;
                    if (row == 0 && getFillColumn(c)) {
                        fills[col] = true;
                    }
                }
            }
            x += w + hgap;
            if (fills[col]) {
                nFills++;
                lastFillCol = col;
            }
        }

        // Fill widths
        if (nFills > 0 && x < parent.getWidth()) {
            // How much width to add
            int wAdd = (parent.getWidth() - x) / nFills;
            int wAdded = 0;
            for (int col = 0; col < ncols; col++) {
                if (fills[col]) {
                    if (col == lastFillCol) {
                        wAdd = parent.getWidth() - (x+wAdded);
                    }
                    for (int row = 0; row < nrows; row++) {
                        if (row * ncols + col < nComps) {
                            Component c = parent.getComponent(row * ncols + col);
                            Rectangle b = c.getBounds();
                            c.setBounds(b.x + wAdded, b.y, b.width + wAdd, b.height);
                        }
                    }
                    wAdded += wAdd;
                }
            }
        }
    }

    public Dimension preferredLayoutSize(Container parent) {
        Insets insets = parent.getInsets();
        int ncomponents = parent.getComponentCount();
        int nrows = getRows();
        int ncols = getColumns();
        int hgap =  getHgap();
        int vgap =  getVgap();

        if (nrows > 0) {
            ncols = (ncomponents + nrows - 1) / nrows;
        } else {
            nrows = (ncomponents + ncols - 1) / ncols;
        }

        int nComps = parent.getComponentCount();

        int y = insets.top;
        for (int row = 0; row < nrows; row++) {
            int h = 0;
            for (int col = 0; col < ncols; col++) {
                if (row * ncols + col < nComps) {
                    Component c = parent.getComponent(row * ncols + col);
                    h = Math.max(h, c.getMinimumSize().height);
                }
            }
            y += h + vgap;
        }

        int x = insets.left;
        for (int col = 0; col < ncols; col++) {
            int w = 0;
            for (int row = 0; row < nrows; row++) {
                if (row * ncols + col < nComps) {
                    Component c = parent.getComponent(row * ncols + col);
                    w = Math.max(w, c.getMinimumSize().width);
                }
            }
            x += w + hgap;
        }
        return new Dimension(x, y);
    }
}