Child nodes of eclipse rcp tree viewer is not shown

Question

I have a tree viewer in the project explorer view of my RCP application. My product completely deals with loading, value retrieval and updating values in resource ("org.eclipse.emf.ecore.resource.Resource"). I am having a create project menu item, which is used for creation of new project. After the project creation operation, a new file is created in the project folder. I am having a standard file, which I need to be loaded while creating the project itself. So, in the entire application, I deal with 2 files(standard file and the file created during project creation operation). When I am running the rcp product in eclipse, its working fine and after the completion of project creation process, the project node appears in the tree and when i try to expand the project node, it shows the child nodes.

I tried to export it as an rcp product in the eclipse product file. And when I tried to create project, the project node is shown in the tree viewer, but when I try to expand the project node, nothing is shown under it. Why is it not showing the child nodes of the project node. The child nodes should be taken from the file created during the project creation process. Th file is created perfectly in the project folder. I think, this happens due to some issues related with resources. Is there something which we should care about resources, while exporting the product.

Answer 1

I've had the same issue and although ugly got around it with this class.

package com.mycomp

import java.net.URL;

import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.Platform;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.ui.application.IWorkbenchConfigurer;
import org.eclipse.ui.application.WorkbenchAdvisor;
import org.eclipse.ui.ide.IDE;
import org.eclipse.ui.internal.ide.IDEInternalWorkbenchImages;
import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin;
import org.eclipse.ui.internal.ide.model.WorkbenchAdapterBuilder;
import org.osgi.framework.Bundle;

public abstract class WorkbenchAdvisorHack extends WorkbenchAdvisor
{
/**
 * Declares all IDE-specific workbench images. This includes both "shared"
 * images (named in {@link IDE.SharedImages}) and internal images (named in
 * {@link org.eclipse.ui.internal.ide.IDEInternalWorkbenchImages}).
 * 
 * @see org.eclipse.ui.internal.ide.IDEWorkbenchAdvisor#declareImage
 */
protected void declareWorkbenchImages()
{
    final String ICONS_PATH = "$nl$/icons/full/";//$NON-NLS-1$
    final String PATH_ELOCALTOOL = ICONS_PATH + "elcl16/"; // Enabled
    // //$NON-NLS-1$

    // toolbar
    // icons.
    final String PATH_DLOCALTOOL = ICONS_PATH + "dlcl16/"; // Disabled
    // //$NON-NLS-1$
    // //$NON-NLS-1$
    // toolbar
    // icons.
    final String PATH_ETOOL = ICONS_PATH + "etool16/"; // Enabled toolbar
    // //$NON-NLS-1$
    // //$NON-NLS-1$
    // icons.
    final String PATH_DTOOL = ICONS_PATH + "dtool16/"; // Disabled toolbar
    // //$NON-NLS-1$
    // //$NON-NLS-1$
    // icons.
    final String PATH_OBJECT = ICONS_PATH + "obj16/"; // Model object
    // //$NON-NLS-1$
    // //$NON-NLS-1$
    // icons
    final String PATH_WIZBAN = ICONS_PATH + "wizban/"; // Wizard
    // //$NON-NLS-1$
    // //$NON-NLS-1$
    // icons

    Bundle ideBundle = Platform.getBundle(IDEWorkbenchPlugin.IDE_WORKBENCH);

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_BUILD_EXEC,
            PATH_ETOOL + "build_exec.gif", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_BUILD_EXEC_HOVER,
            PATH_ETOOL + "build_exec.gif", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_BUILD_EXEC_DISABLED,
            PATH_DTOOL + "build_exec.gif", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_SEARCH_SRC,
            PATH_ETOOL + "search_src.gif", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_SEARCH_SRC_HOVER,
            PATH_ETOOL + "search_src.gif", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_SEARCH_SRC_DISABLED,
            PATH_DTOOL + "search_src.gif", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_NEXT_NAV, PATH_ETOOL
            + "next_nav.gif", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_PREVIOUS_NAV,
            PATH_ETOOL + "prev_nav.gif", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_NEWPRJ_WIZ,
            PATH_WIZBAN + "newprj_wiz.png", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_NEWFOLDER_WIZ,
            PATH_WIZBAN + "newfolder_wiz.png", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_NEWFILE_WIZ,
            PATH_WIZBAN + "newfile_wiz.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_IMPORTDIR_WIZ,
            PATH_WIZBAN + "importdir_wiz.png", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_IMPORTZIP_WIZ,
            PATH_WIZBAN + "importzip_wiz.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_EXPORTDIR_WIZ,
            PATH_WIZBAN + "exportdir_wiz.png", false); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_WIZBAN_EXPORTZIP_WIZ,
            PATH_WIZBAN + "exportzip_wiz.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle,
            IDEInternalWorkbenchImages.IMG_WIZBAN_RESOURCEWORKINGSET_WIZ, PATH_WIZBAN
                    + "workset_wiz.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_DLGBAN_SAVEAS_DLG,
            PATH_WIZBAN + "saveas_wiz.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_DLGBAN_QUICKFIX_DLG,
            PATH_WIZBAN + "quick_fix.png", false); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDE.SharedImages.IMG_OBJ_PROJECT, PATH_OBJECT
            + "prj_obj.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDE.SharedImages.IMG_OBJ_PROJECT_CLOSED, PATH_OBJECT
            + "cprj_obj.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDE.SharedImages.IMG_OPEN_MARKER, PATH_ELOCALTOOL
            + "gotoobj_tsk.gif", true); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ELCL_QUICK_FIX_ENABLED,
            PATH_ELOCALTOOL + "smartmode_co.gif", true); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_DLCL_QUICK_FIX_DISABLED,
            PATH_DLOCALTOOL + "smartmode_co.gif", true); //$NON-NLS-1$

    // task objects
    // declareRegistryImage(IDEInternalWorkbenchImages.IMG_OBJS_HPRIO_TSK,
    // PATH_OBJECT+"hprio_tsk.gif");
    // declareRegistryImage(IDEInternalWorkbenchImages.IMG_OBJS_MPRIO_TSK,
    // PATH_OBJECT+"mprio_tsk.gif");
    // declareRegistryImage(IDEInternalWorkbenchImages.IMG_OBJS_LPRIO_TSK,
    // PATH_OBJECT+"lprio_tsk.gif");

    declareWorkbenchImage(ideBundle, IDE.SharedImages.IMG_OBJS_TASK_TSK, PATH_OBJECT
            + "taskmrk_tsk.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDE.SharedImages.IMG_OBJS_BKMRK_TSK, PATH_OBJECT
            + "bkmrk_tsk.gif", true); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_COMPLETE_TSK,
            PATH_OBJECT + "complete_tsk.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_INCOMPLETE_TSK,
            PATH_OBJECT + "incomplete_tsk.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_WELCOME_ITEM,
            PATH_OBJECT + "welcome_item.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_WELCOME_BANNER,
            PATH_OBJECT + "welcome_banner.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_ERROR_PATH,
            PATH_OBJECT + "error_tsk.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_WARNING_PATH,
            PATH_OBJECT + "warn_tsk.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_OBJS_INFO_PATH, PATH_OBJECT
            + "info_tsk.gif", true); //$NON-NLS-1$

    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_LCL_FLAT_LAYOUT,
            PATH_ELOCALTOOL + "flatLayout.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_LCL_HIERARCHICAL_LAYOUT,
            PATH_ELOCALTOOL + "hierarchicalLayout.gif", true); //$NON-NLS-1$
    declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_ETOOL_PROBLEM_CATEGORY,
            PATH_ETOOL + "problem_category.gif", true); //$NON-NLS-1$
/*  declareWorkbenchImage(ideBundle, IDEInternalWorkbenchImages.IMG_LCL_LINKTO_HELP,
            PATH_ELOCALTOOL + "linkto_help.gif", false); //$NON-NLS-1$
*/  }

/**
 * Declares an IDE-specific workbench image.
 * 
 * @param symbolicName
 *            the symbolic name of the image
 * @param path
 *            the path of the image file; this path is relative to the base
 *            of the IDE plug-in
 * @param shared
 *            <code>true</code> if this is a shared image, and
 *            <code>false</code> if this is not a shared image
 * @see org.eclipse.ui.internal.ide.IDEWorkbenchAdvisor#declareImage
 */
private void declareWorkbenchImage(Bundle ideBundle, String symbolicName, String path,
        boolean shared)
{
    URL url = FileLocator.find(ideBundle, new Path(path), null);
    ImageDescriptor desc = ImageDescriptor.createFromURL(url);
    getWorkbenchConfigurer().declareImage(symbolicName, desc, shared);
}

@Override
public void initialize(IWorkbenchConfigurer configurer)
{
    //configurer.setSaveAndRestore(true);
    declareWorkbenchImages();
}

@Override
public IAdaptable getDefaultPageInput()
{
    return ResourcesPlugin.getWorkspace().getRoot();
}

@SuppressWarnings("restriction")
@Override
public void preStartup()
{
    WorkbenchAdapterBuilder.registerAdapters();
}
}

It is an issue of ui resources not getting set also you need this extension point "org.eclipse.ui.navigator.viewer" to create a viewer with the view id of your project explorer. Hope that helps.