org.springsource.ide.eclipse.commons.livexp.ui.PreferencePageWithSections.java Source code

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Here is the source code for org.springsource.ide.eclipse.commons.livexp.ui.PreferencePageWithSections.java

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/*******************************************************************************
 * Copyright (c) 2013, 2015 Pivotal Software, Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 * Pivotal Software, Inc. - initial API and implementation
 *******************************************************************************/
package org.springsource.ide.eclipse.commons.livexp.ui;

import java.util.List;

import org.eclipse.core.runtime.IStatus;
import org.eclipse.jface.dialogs.IMessageProvider;
import org.eclipse.jface.operation.IRunnableContext;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.ui.PlatformUI;
import org.springsource.ide.eclipse.commons.livexp.core.CompositeValidator;
import org.springsource.ide.eclipse.commons.livexp.core.LiveExpression;
import org.springsource.ide.eclipse.commons.livexp.core.ValidationResult;
import org.springsource.ide.eclipse.commons.livexp.core.ValueListener;

/**
 * An abstract super class to more easily create preferences pages composed of modular sections.
 * Each section encapsulates its own widgetry and validation logic.
 *
 * @author Kris De Volder
 */
public abstract class PreferencePageWithSections extends PreferencePage
        implements IWorkbenchPreferencePage, ValueListener<ValidationResult>, IPageWithSections {

    private List<PrefsPageSection> sections = null;

    public PreferencePageWithSections() {
    }

    public void init(IWorkbench workbench) {
    }

    /**
     * This method should be implemented to generate the contents of the page.
     */
    protected abstract List<PrefsPageSection> createSections();

    @Override
    protected Control createContents(Composite parent) {
        final Composite page = new Composite(parent, SWT.NONE);
        GridLayout layout = new GridLayout(1, false);
        layout.marginHeight = 1;
        layout.marginWidth = 1;
        page.setLayout(layout);
        CompositeValidator validator = new CompositeValidator();
        for (PrefsPageSection section : getSections()) {
            section.createContents(page);
            validator.addChild(section.getValidator());
        }
        validator.addListener(this);

        //Listener below is workaround for a layout glitch. Seems
        // we occasionally need to trigger an additional 'layout'
        // the first time the page is drawn. Otherwise widgets
        // aren't properly layed out until the page is
        // being resized.
        Listener listener = new Listener() {
            @Override
            public void handleEvent(Event event) {
                page.getShell().layout(true, true);
                page.getShell().redraw();
                page.removeListener(event.type, this);
            }
        };
        page.addListener(SWT.Paint, listener);
        return page;
    }

    @Override
    public boolean performOk() {
        for (PrefsPageSection section : getSections()) {
            boolean ok = section.performOK();
            if (!ok) {
                return false;
            }
        }
        //We reach here only when all sections performOK returned true
        return true;
    }

    private synchronized List<PrefsPageSection> getSections() {
        if (sections == null) {
            sections = createSections();
        }
        return sections;
    }

    @Override
    protected void performDefaults() {
        super.performDefaults();
        for (PrefsPageSection section : getSections()) {
            section.performDefaults();
        }
    }

    public void gotValue(LiveExpression<ValidationResult> exp, ValidationResult status) {
        Display.getDefault().asyncExec(() -> {
            setErrorMessage(null);
            setMessage(null);
            if (status.isOk()) {
            } else if (status.status == IStatus.ERROR) {
                setErrorMessage(status.msg);
            } else if (status.status == IStatus.WARNING) {
                setMessage(status.msg, IMessageProvider.WARNING);
            } else if (status.status == IStatus.INFO) {
                setMessage(status.msg, IMessageProvider.INFORMATION);
            } else {
                setMessage(status.msg, IMessageProvider.NONE);
            }
        });
    }

    public IRunnableContext getRunnableContext() {
        //TODO: can we do something more specific for preferences page?
        return PlatformUI.getWorkbench().getProgressService();
    }
}