[NETBEANS-3355] SideBarFactory painting offset with large files

• Type: Bug
• Status: Reopened
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 8.2, 11.0
• Assignee: Unassigned
• Reporter: Benedikt Schlagberger
• Created: 07/Nov/19 18:36
• Updated: 01/Mar/21 10:32

Description

When painting in the sidebar using the SideBarFactory, the painted Graphic is offset for large files. To reproduce, create a NetBeans plugin project and add the following class:

package com.mycompany.sidebar_test;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.JComponent;
import javax.swing.text.JTextComponent;
import org.netbeans.spi.editor.SideBarFactory;

public class MySidebarFactory implements SideBarFactory {
    @Override
    public JComponent createSideBar(JTextComponent jtc) {
        return new MySidebar();
    }

    private class MySidebar extends JComponent {
        @Override
        protected void paintComponent(Graphics g) {
            g.setColor(Color.BLUE);
            g.fillRect(0, 0, 10, 1000); // Paint blue rectangle starting at the top of the sidebar with height of 1000px 
        }

        @Override
        public Dimension getPreferredSize() {
            Dimension dimension = new Dimension(this.getParent().getSize());
            dimension.width = 10;

            return dimension;
        }
    }
}

Register the SideBarFactory using the following layers.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE filesystem PUBLIC "-//NetBeans//DTD Filesystem 1.2//EN" "http://www.netbeans.org/dtds/filesystem-1_2.dtd">
<filesystem>
    <folder name="Editors">
        <folder name="SideBar">
            <file name="com-mycompany-sidebar_test-MySidebarFactory.instance">
                <attr name="location" stringvalue="West"/>
            </file>
        </folder>
    </folder>
</filesystem>

Now start the plugin and open a project containing a large file for example the StrBuilder.java from the apache commons lib.

The painting is offset by a large amount as you can see in the attached screenshot (blue rectangle should start in line 1, not 2150). When shortening the file and re-opening it, the marker moves, so I suppose this is related to the file size.