ComboDialogField.java

/*
* Copyright (c) 2010-2012 Research In Motion Limited. All rights reserved.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Public License, Version 1.0,
* which accompanies this distribution and is available at
*
* http://www.eclipse.org/legal/epl-v10.html
*
*/
package net.rim.ejde.internal.ui.widgets.dialog;

import org.eclipse.jdt.internal.ui.util.SWTUtil;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;

/**
 * Dialog field containing a label and a combo control.
 */
public class ComboDialogField extends DialogField {

    private String fText;
    private int fSelectionIndex;
    private String[] fItems;
    private Combo fComboControl;
    private ModifyListener fModifyListener;
    private int fFlags;

    public ComboDialogField( int flags ) {
        super();
        fText = ""; //$NON-NLS-1$
        fItems = new String[ 0 ];
        fFlags = flags;
        fSelectionIndex = -1;
    }

    // ------- layout helpers

    /*
     * @see DialogField#doFillIntoGrid
     */
    public Control[] doFillIntoGrid( Composite parent, int nColumns ) {
        assertEnoughColumns( nColumns );

        Label label = getLabelControl( parent );
        label.setLayoutData( gridDataForLabel( 1 ) );
        Combo combo = getComboControl( parent );
        combo.setLayoutData( gridDataForCombo( nColumns - 1 ) );

        return new Control[] { label, combo };
    }

    /*
     * @see DialogField#getNumberOfControls
     */
    public int getNumberOfControls() {
        return 2;
    }

    protected static GridData gridDataForCombo( int span ) {
        GridData gd = new GridData();
        gd.horizontalAlignment = GridData.FILL;
        gd.grabExcessHorizontalSpace = false;
        gd.horizontalSpan = span;
        return gd;
    }

    // ------- focus methods

    /*
     * @see DialogField#setFocus
     */
    public boolean setFocus() {
        if( isOkToUse( fComboControl ) ) {
            fComboControl.setFocus();
        }
        return true;
    }

    // ------- ui creation

    /**
     * Creates or returns the created combo control.
     *
     * @param parent
     *            The parent composite or <code>null</code> when the widget has already been created.
     */
    public Combo getComboControl( Composite parent ) {
        if( fComboControl == null ) {
            assertCompositeNotNull( parent );
            fModifyListener = new ModifyListener() {
                public void modifyText( ModifyEvent e ) {
                    doModifyText( e );
                }
            };
            SelectionListener selectionListener = new SelectionListener() {
                public void widgetSelected( SelectionEvent e ) {
                    doSelectionChanged( e );
                }

                public void widgetDefaultSelected( SelectionEvent e ) {
                }
            };

            fComboControl = new Combo( parent, fFlags );
            // moved up due to 1GEUNW2
            fComboControl.setItems( fItems );
            if( fSelectionIndex != -1 ) {
                fComboControl.select( fSelectionIndex );
            } else {
                fComboControl.setText( fText );
            }
            fComboControl.setFont( parent.getFont() );
            SWTUtil.setDefaultVisibleItemCount( fComboControl );
            fComboControl.addModifyListener( fModifyListener );
            fComboControl.addSelectionListener( selectionListener );
            fComboControl.setEnabled( isEnabled() );
        }
        return fComboControl;
    }

    private void doModifyText( ModifyEvent e ) {
        if( isOkToUse( fComboControl ) ) {
            fText = fComboControl.getText();
            fSelectionIndex = fComboControl.getSelectionIndex();
        }
        dialogFieldChanged();
    }

    private void doSelectionChanged( SelectionEvent e ) {
        if( isOkToUse( fComboControl ) ) {
            fItems = fComboControl.getItems();
            fText = fComboControl.getText();
            fSelectionIndex = fComboControl.getSelectionIndex();
        }
        dialogFieldChanged();
    }

    // ------ enable / disable management

    /*
     * @see DialogField#updateEnableState
     */
    protected void updateEnableState() {
        super.updateEnableState();
        if( isOkToUse( fComboControl ) ) {
            fComboControl.setEnabled( isEnabled() );
        }
    }

    // ------ text access

    /**
     * Gets the combo items.
     */
    public String[] getItems() {
        return fItems;
    }

    /**
     * Sets the combo items. Triggers a dialog-changed event.
     */
    public void setItems( String[] items ) {
        fItems = items;
        if( isOkToUse( fComboControl ) ) {
            fComboControl.setItems( items );
        }
        dialogFieldChanged();
    }

    /**
     * Gets the text.
     */
    public String getText() {
        return fText;
    }

    /**
     * Sets the text. Triggers a dialog-changed event.
     */
    public void setText( String text ) {
        fText = text;
        if( isOkToUse( fComboControl ) ) {
            fComboControl.setText( text );
        } else {
            dialogFieldChanged();
        }
    }

    /**
     * Selects an item.
     */
    public boolean selectItem( int index ) {
        boolean success = false;
        if( isOkToUse( fComboControl ) ) {
            fComboControl.select( index );
            success = fComboControl.getSelectionIndex() == index;
        } else {
            if( index >= 0 && index < fItems.length ) {
                fText = fItems[ index ];
                fSelectionIndex = index;
                success = true;
            }
        }
        if( success ) {
            dialogFieldChanged();
        }
        return success;
    }

    /**
     * Selects an item.
     */
    public boolean selectItem( String name ) {
        for( int i = 0; i < fItems.length; i++ ) {
            if( fItems[ i ].equals( name ) ) {
                return selectItem( i );
            }
        }
        return false;
    }

    public int getSelectionIndex() {
        return fSelectionIndex;
    }

    /**
     * Sets the text without triggering a dialog-changed event.
     */
    public void setTextWithoutUpdate( String text ) {
        fText = text;
        if( isOkToUse( fComboControl ) ) {
            fComboControl.removeModifyListener( fModifyListener );
            fComboControl.setText( text );
            fComboControl.addModifyListener( fModifyListener );
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.eclipse.jdt.internal.ui.wizards.dialogfields.DialogField#refresh()
     */
    public void refresh() {
        super.refresh();
        setTextWithoutUpdate( fText );
    }

}