kieker.develop.rl.ui.preferences.CommentFieldEditor.java Source code

Introduction

Here is the source code for kieker.develop.rl.ui.preferences.CommentFieldEditor.java

Source

/***************************************************************************
 * Copyright 2016 Kieker Project (http://kieker-monitoring.net)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ***************************************************************************/
package kieker.develop.rl.ui.preferences;

import org.eclipse.jface.preference.FieldEditor;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.Bullet;
import org.eclipse.swt.custom.LineStyleEvent;
import org.eclipse.swt.custom.LineStyleListener;
import org.eclipse.swt.custom.ST;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.graphics.GlyphMetrics;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;

/**
 * Editor for a the header comment fields in the preference tab.
 *
 * @author Reiner Jung
 *
 */
public class CommentFieldEditor extends FieldEditor {

    private Composite top;
    private StyledText commentText;

    /**
     * Constructor for the comment field.
     *
     * @param name the name of the editor
     * @param label the label of the editor
     * @param fieldEditorParent the context where the editor is placed in
     */
    public CommentFieldEditor(final String name, final String label, final Composite fieldEditorParent) {
        super(name, label, fieldEditorParent);
    }

    @Override
    protected void adjustForNumColumns(final int numColumns) {
        ((GridData) this.top.getLayoutData()).horizontalSpan = numColumns;
    }

    @Override
    protected void doFillIntoGrid(final Composite parent, final int numColumns) {
        this.top = parent;

        final GridData gd = new GridData(GridData.FILL_HORIZONTAL);
        gd.horizontalSpan = numColumns;
        this.top.setLayoutData(gd);

        final Label label = this.getLabelControl(this.top);
        final GridData labelData = new GridData();
        labelData.horizontalSpan = numColumns;
        label.setLayoutData(labelData);

        this.commentText = new StyledText(this.top, SWT.MULTI | SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL);
        final GridData layoutData = new GridData(GridData.FILL_BOTH);
        layoutData.heightHint = this.convertVerticalDLUsToPixels(parent, 50);
        this.commentText.setLayoutData(layoutData);

        this.commentText.addLineStyleListener(new LineStyleListener() {
            @Override
            public void lineGetStyle(final LineStyleEvent event) {
                // Using ST.BULLET_NUMBER sometimes results in weird alignment.
                //event.bulletIndex = styledText.getLineAtOffset(event.lineOffset);
                final StyleRange styleRange = new StyleRange();
                styleRange.foreground = Display.getCurrent().getSystemColor(SWT.COLOR_GRAY);
                final int maxLine = CommentFieldEditor.this.commentText.getLineCount();
                final int bulletLength = Integer.toString(maxLine).length();
                // Width of number character is half the height in monospaced font, add 1 character width for right padding.
                final int bulletWidth = ((bulletLength + 1) * CommentFieldEditor.this.commentText.getLineHeight())
                        / 2;
                styleRange.metrics = new GlyphMetrics(0, 0, bulletWidth);
                event.bullet = new Bullet(ST.BULLET_TEXT, styleRange);
                // getLineAtOffset() returns a zero-based line index.
                final int bulletLine = CommentFieldEditor.this.commentText.getLineAtOffset(event.lineOffset) + 1;
                event.bullet.text = String.format("%" + bulletLength + "s", bulletLine);
            }
        });

        this.commentText.addModifyListener(new ModifyListener() {
            @Override
            public void modifyText(final ModifyEvent e) {
                // For line number redrawing.
                CommentFieldEditor.this.commentText.redraw();
            }
        });

    }

    @Override
    protected void doLoad() {
        final String comment = this.getPreferenceStore().getString(this.getPreferenceName());
        if (comment != null) {
            this.commentText.setText(comment);
        }
    }

    @Override
    protected void doLoadDefault() {
        final String comment = this.getPreferenceStore().getDefaultString(this.getPreferenceName());
        if (comment != null) {
            this.commentText.setText(comment);
        }
    }

    @Override
    protected void doStore() {
        this.getPreferenceStore().setValue(this.getPreferenceName(), this.commentText.getText());
    }

    @Override
    public int getNumberOfControls() {
        return 1;
    }

}