erer.flying-saucer-examples.9.9.4.source-code.PanelResizeToPreferredSize Maven / Gradle / Ivy
Show all versions of flying-saucer-examples Show documentation
/*
* {{{ header & license
* Copyright (c) 2008 Patrick Wright
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1
* of the License, or (at your option) any later version.
*
* This program 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
* }}}
*/
import org.xhtmlrenderer.simple.XHTMLPanel;
import org.xhtmlrenderer.simple.extend.XhtmlNamespaceHandler;
import javax.swing.*;
import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
/**
* This sample shows how to size a panel based on the content of a document, when using a layout manager
* that relies on preferred size. The class was attached as part of an email discussion:
*
* From the email thread: "The panel doesn't get a preferred size until layout is called (which,
* in turn, happens the first time it's painted). This means you're not
* going to get the results you want if your XHTMLPanel is managed by a
* layout manager that relies on preferred size (e.g. FlowLayout).
* Assuming you want to lay the document out into some width, you'll want
* to use a layout manager that doesn't rely (entirely) on preferred
* size.
*
* If you need the entirely unconstrained document width, you could
* temporarily boost the size of the XHTMLPanel to something very large
* and then call panel.doLayout() and then read back the panel's
* preferred size. Needless to say, this all needs to happen on the EDT."
* and: "So basically you want to:
* 1) create the frame and add components to it
* 2) call f.pack() to make them displayable
* 3) layout documents in XHTMLPanel instances
* 4) call f.pack() again now that the preferred size of the XHTMLPanel
* instances has been calculated"
*/
public class PanelResizeToPreferredSize {
public static void main(String[] args) throws Exception {
final JFrame f = new JFrame("XHTMLPanel");
f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
Container content = f.getContentPane();
content.setBackground(Color.white);
// Note: we're using a layout manager that depends on the preferred size of its components.
// That's the critical point of this sample code.
content.setLayout(new FlowLayout());
content.add(new JButton("Button 1"));
final XHTMLPanel panel = new XHTMLPanel();
content.add(panel);
content.add(new JButton("Button 2"));
content.add(new JButton("Button 3"));
// Calling pack() will cause the frame and its components to be displayable (see javadoc for {@link java.awt.Window.pack});
// this is critical for the document layout routine, below, to have any effect
// Note the frame doesn't need to be visible; e.g., we don't need to show the frame, layout the document,
// then resize the window; it just needs to be displayable.
f.pack();
SwingUtilities.invokeAndWait(() -> {
// Note that our document doesn't have any width constraints, but that there is very little text
// involved, so the document width (calculated from the content) is something reasonable for this demo.
panel.setDocumentFromString(
"" +
" Several words that won't wrap" +
"",
null,
new XhtmlNamespaceHandler());
Dimension savedSize = panel.getSize();
// Set the panel size to some artificially large size; the render engine will actually calculate
// the actual (preferred) size based on the document content. Setting it to a large size here prevents
// the document from being artificially constrained by the panel's width.
// If the document had very long runs of text, and no width constraints, we'd want to set the width
// to some smaller, reasonable value (800, 1024, etc.). Without that, in the absence of any other
// information, the render engine would lay out the runs of text to as wide a space as needed to
// accommodate the text without breaks.
panel.setSize(10000, 10000);
// now we lay the document out again
panel.doDocumentLayout(panel.getGraphics());
// and reset the size
panel.setSize(savedSize);
f.pack();
f.setVisible(true);
});
}
}