org.eclipse.rap.demo.databinding.Snippet004DataBindingContextErrorLabel.java Source code

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Here is the source code for org.eclipse.rap.demo.databinding.Snippet004DataBindingContextErrorLabel.java

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/*******************************************************************************
 * Copyright (c) 2006, 2012 Brad Reynolds and others.
 * 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:
 *    Brad Reynolds - initial API and implementation
 *    Brad Reynolds - bug 116920
 *    Samy Abou-Shama - adapted for RAP and implemented Snippet as Control
 *    EclipseSource - ongoing development
 ******************************************************************************/
package org.eclipse.rap.demo.databinding;

import org.eclipse.core.databinding.*;
import org.eclipse.core.databinding.observable.Realm;
import org.eclipse.core.databinding.observable.value.WritableValue;
import org.eclipse.core.databinding.validation.IValidator;
import org.eclipse.core.databinding.validation.ValidationStatus;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.databinding.swt.SWTObservables;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.internal.graphics.Graphics;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

/**
 * Snippet that displays how to bind the validation error of the
 * {@link DataBindingContext} to a label.
 * 
 * @since 1.0
 */
public class Snippet004DataBindingContextErrorLabel extends Group {

    /**
     * Validator that returns validation errors for any value other than 5.
     * 
     * @since 1.0
     */
    private static class FiveValidator implements IValidator {
        public IStatus validate(final Object value) {
            String msg = "the value was '" + value + "', not '5'";
            return "5".equals(value) ? Status.OK_STATUS : ValidationStatus.error(msg);
        }
    }

    public Snippet004DataBindingContextErrorLabel(final Composite parent, final int style) {
        super(parent, style);
        createPartControl();
    }

    public void createPartControl() {
        // Initiating the realm
        Realm realm = SWTObservables.getRealm(Display.getCurrent());
        FormLayout formLayout = new FormLayout();
        formLayout.marginHeight = DatabindingSnippetsView.GROUP_MARGIN_HEIGHT;
        formLayout.marginWidth = DatabindingSnippetsView.GROUP_MARGIN_WIDTH;
        setLayout(formLayout);
        setText("Context Error Label Snippet 004 - Binding Example");
        Label info1 = new Label(this, SWT.NONE);
        info1.setText("Enter '5' to be valid:");
        FormData data = new FormData(DatabindingSnippetsView.STD_LABEL_WIDTH_LARGE, SWT.DEFAULT);
        data.top = new FormAttachment(0, DatabindingSnippetsView.TOP_MARGIN);
        data.left = new FormAttachment(0, 0);
        info1.setLayoutData(data);
        Text text = new Text(this, SWT.BORDER);
        WritableValue value = new WritableValue(realm, null, String.class);
        data = new FormData(DatabindingSnippetsView.STD_LABEL_WIDTH_LARGE, SWT.DEFAULT);
        data.top = new FormAttachment(0, DatabindingSnippetsView.TOP_MARGIN);
        data.left = new FormAttachment(info1, 0);
        text.setLayoutData(data);
        Label info2 = new Label(this, SWT.NONE);
        info2.setText("Error/Validation:");
        data = new FormData(DatabindingSnippetsView.STD_LABEL_WIDTH_LARGE, SWT.DEFAULT);
        data.top = new FormAttachment(info1, DatabindingSnippetsView.TOP_MARGIN);
        data.left = new FormAttachment(0, 0);
        info2.setLayoutData(data);
        Label errorLabel = new Label(this, SWT.BORDER);
        Color color = Graphics.getColor(255, 0, 0);
        errorLabel.setForeground(color);
        data = new FormData(DatabindingSnippetsView.STD_TEXT_WIDTH_LARGE, SWT.DEFAULT);
        data.top = new FormAttachment(text, DatabindingSnippetsView.TOP_MARGIN);
        data.left = new FormAttachment(info2, 0);
        errorLabel.setLayoutData(data);
        errorLabel.setText("hallo");
        DataBindingContext dbc = new DataBindingContext(realm);
        // Bind the text to the value.
        UpdateValueStrategy updateValueStrategy = new UpdateValueStrategy();
        updateValueStrategy.setAfterConvertValidator(new FiveValidator());
        dbc.bindValue(SWTObservables.observeText(text, SWT.Modify), value, updateValueStrategy, null);
        // Bind the error label to the validation error on the dbc.
        int severity = AggregateValidationStatus.MAX_SEVERITY;
        AggregateValidationStatus aggregateValidationStatus = new AggregateValidationStatus(realm,
                dbc.getBindings(), severity);
        dbc.bindValue(SWTObservables.observeText(errorLabel), aggregateValidationStatus, null, null);
    }
}