/******************************************************************************* * Copyright (c) 2000, 2008 IBM Corporation 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: * IBM Corporation - initial API and implementation * Cloudsmith Inc - edit button *******************************************************************************/ package org.cloudsmith.geppetto.pp.dsl.ui.preferences.editors; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.preference.FieldEditor; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.swt.SWT; import org.eclipse.swt.events.DisposeEvent; import org.eclipse.swt.events.DisposeListener; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.List; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Widget; /** * An abstract field editor that manages a list of input values. * The editor displays a list containing the values, buttons for * adding and removing values, and Up and Down buttons to adjust * the order of elements in the list. * <p> * Subclasses must implement the <code>parseString</code>, <code>createList</code>, and <code>getNewInputObject</code> framework methods. * </p> */ public abstract class ListEditor extends FieldEditor { /** * The list widget; <code>null</code> if none * (before creation or after disposal). */ private List list; /** * The button box containing the Add, Remove, Up, and Down buttons; <code>null</code> if none (before creation or after disposal). */ private Composite buttonBox; /** * The Add button. */ private Button addButton; /** * The Edit button. */ private Button editButton; /** * The Remove button. */ private Button removeButton; /** * The Up button. */ private Button upButton; /** * The Down button. */ private Button downButton; /** * The selection listener. */ private SelectionListener selectionListener; /** * Creates a new list field editor */ protected ListEditor() { } /** * Creates a list field editor. * * @param name * the name of the preference this field editor works on * @param labelText * the label text of the field editor * @param parent * the parent of the field editor's control */ protected ListEditor(String name, String labelText, Composite parent) { init(name, labelText); createControl(parent); } /** * Notifies that the Add button has been pressed. */ private void addPressed() { setPresentsDefaultValue(false); String input = getNewInputObject(); if(input != null) { int index = list.getSelectionIndex(); if(index >= 0) { list.add(input, index + 1); } else { list.add(input, 0); } selectionChanged(); } } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override protected void adjustForNumColumns(int numColumns) { Control control = getLabelControl(); ((GridData) control.getLayoutData()).horizontalSpan = numColumns; ((GridData) list.getLayoutData()).horizontalSpan = numColumns - 1; } /** * Creates the Add, Remove, Up, and Down button in the given button box. * * @param box * the box for the buttons */ private void createButtons(Composite box) { addButton = createPushButton(box, "ListEditor.add");//$NON-NLS-1$ // TODO: the createPushButton expects a key, this is sheeting editButton = createPushButton(box, "Edit"); removeButton = createPushButton(box, "ListEditor.remove");//$NON-NLS-1$ upButton = createPushButton(box, "ListEditor.up");//$NON-NLS-1$ downButton = createPushButton(box, "ListEditor.down");//$NON-NLS-1$ } /** * Combines the given list of items into a single string. * This method is the converse of <code>parseString</code>. * <p> * Subclasses must implement this method. * </p> * * @param items * the list of items * @return the combined string * @see #parseString */ protected abstract String createList(String[] items); /** * Helper method to create a push button. * * @param parent * the parent control * @param key * the resource name used to supply the button's label text * @return Button */ private Button createPushButton(Composite parent, String key) { Button button = new Button(parent, SWT.PUSH); button.setText(JFaceResources.getString(key)); button.setFont(parent.getFont()); GridData data = new GridData(GridData.FILL_HORIZONTAL); int widthHint = convertHorizontalDLUsToPixels(button, IDialogConstants.BUTTON_WIDTH); data.widthHint = Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x); button.setLayoutData(data); button.addSelectionListener(getSelectionListener()); return button; } /** * Creates a selection listener. */ public void createSelectionListener() { selectionListener = new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent event) { Widget widget = event.widget; if(widget == addButton) { addPressed(); } else if(widget == editButton) { editPressed(); } else if(widget == removeButton) { removePressed(); } else if(widget == upButton) { upPressed(); } else if(widget == downButton) { downPressed(); } else if(widget == list) { selectionChanged(); } } }; } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override protected void doFillIntoGrid(Composite parent, int numColumns) { Control control = getLabelControl(parent); GridData gd = new GridData(); gd.horizontalSpan = numColumns; control.setLayoutData(gd); list = getListControl(parent); gd = new GridData(GridData.FILL_HORIZONTAL); gd.verticalAlignment = GridData.FILL; gd.horizontalSpan = numColumns - 1; gd.grabExcessHorizontalSpace = true; list.setLayoutData(gd); buttonBox = getButtonBoxControl(parent); gd = new GridData(); gd.verticalAlignment = GridData.BEGINNING; buttonBox.setLayoutData(gd); } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override protected void doLoad() { if(list != null) { String s = getPreferenceStore().getString(getPreferenceName()); String[] array = parseString(s); for(int i = 0; i < array.length; i++) { list.add(array[i]); } } } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override protected void doLoadDefault() { if(list != null) { list.removeAll(); String s = getPreferenceStore().getDefaultString(getPreferenceName()); String[] array = parseString(s); for(int i = 0; i < array.length; i++) { list.add(array[i]); } } } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override protected void doStore() { String s = createList(list.getItems()); if(s != null) { getPreferenceStore().setValue(getPreferenceName(), s); } } /** * Notifies that the Down button has been pressed. */ private void downPressed() { swap(false); } private void editPressed() { int index = list.getSelectionIndex(); if(index < 0) return; // nothing to edit String input = list.getItem(index); String output = getEditedInput(input); if(output == null || output.length() == 0) { // remove it setPresentsDefaultValue(false); list.remove(index); selectionChanged(); return; } if(input.equals(output)) return; // no change setPresentsDefaultValue(false); list.setItem(index, output); selectionChanged(); } /** * Return the Add button. * * @return the button * @since 3.5 */ protected Button getAddButton() { return addButton; } /** * Returns this field editor's button box containing the Add, Remove, * Up, and Down button. * * @param parent * the parent control * @return the button box */ public Composite getButtonBoxControl(Composite parent) { if(buttonBox == null) { buttonBox = new Composite(parent, SWT.NULL); GridLayout layout = new GridLayout(); layout.marginWidth = 0; buttonBox.setLayout(layout); createButtons(buttonBox); buttonBox.addDisposeListener(new DisposeListener() { public void widgetDisposed(DisposeEvent event) { addButton = null; editButton = null; removeButton = null; upButton = null; downButton = null; buttonBox = null; } }); } else { checkParent(buttonBox, parent); } selectionChanged(); return buttonBox; } /** * Return the Down button. * * @return the button * @since 3.5 */ protected Button getDownButton() { return downButton; } /** * Returns an (possibly) edited (or empty) version of the input string. * * @param input * @return an edited version, or empty or null if it should be removed. */ protected abstract String getEditedInput(String input); /** * Return the List. * * @return the list * @since 3.5 */ protected List getList() { return list; } /** * Returns this field editor's list control. * * @param parent * the parent control * @return the list control */ public List getListControl(Composite parent) { if(list == null) { list = new List(parent, SWT.BORDER | SWT.SINGLE | SWT.V_SCROLL | SWT.H_SCROLL); list.setFont(parent.getFont()); list.addSelectionListener(getSelectionListener()); list.addDisposeListener(new DisposeListener() { public void widgetDisposed(DisposeEvent event) { list = null; } }); } else { checkParent(list, parent); } return list; } /** * Creates and returns a new item for the list. * <p> * Subclasses must implement this method. * </p> * * @return a new item */ protected abstract String getNewInputObject(); /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override public int getNumberOfControls() { return 2; } /** * Return the Remove button. * * @return the button * @since 3.5 */ protected Button getRemoveButton() { return removeButton; } /** * Returns this field editor's selection listener. * The listener is created if nessessary. * * @return the selection listener */ private SelectionListener getSelectionListener() { if(selectionListener == null) { createSelectionListener(); } return selectionListener; } /** * Returns this field editor's shell. * <p> * This method is internal to the framework; subclassers should not call this method. * </p> * * @return the shell */ protected Shell getShell() { if(addButton == null) { return null; } return addButton.getShell(); } /** * Return the Up button. * * @return the button * @since 3.5 */ protected Button getUpButton() { return upButton; } /** * Splits the given string into a list of strings. * This method is the converse of <code>createList</code>. * <p> * Subclasses must implement this method. * </p> * * @param stringList * the string * @return an array of <code>String</code> * @see #createList */ protected abstract String[] parseString(String stringList); /** * Notifies that the Remove button has been pressed. */ private void removePressed() { setPresentsDefaultValue(false); int index = list.getSelectionIndex(); if(index >= 0) { list.remove(index); selectionChanged(); } } /** * Invoked when the selection in the list has changed. * * <p> * The default implementation of this method utilizes the selection index and the size of the list to toggle the enablement of the up, down and * remove buttons. * </p> * * <p> * Sublcasses may override. * </p> * * @since 3.5 */ protected void selectionChanged() { int index = list.getSelectionIndex(); int size = list.getItemCount(); removeButton.setEnabled(index >= 0); upButton.setEnabled(size > 1 && index > 0); downButton.setEnabled(size > 1 && index >= 0 && index < size - 1); editButton.setEnabled(size > 1 && index >= 0 && index < size); } /* * @see FieldEditor.setEnabled(boolean,Composite). */ @Override public void setEnabled(boolean enabled, Composite parent) { super.setEnabled(enabled, parent); getListControl(parent).setEnabled(enabled); addButton.setEnabled(enabled); removeButton.setEnabled(enabled); upButton.setEnabled(enabled); downButton.setEnabled(enabled); } /* * (non-Javadoc) * Method declared on FieldEditor. */ @Override public void setFocus() { if(list != null) { list.setFocus(); } } /** * Moves the currently selected item up or down. * * @param up * <code>true</code> if the item should move up, * and <code>false</code> if it should move down */ private void swap(boolean up) { setPresentsDefaultValue(false); int index = list.getSelectionIndex(); int target = up ? index - 1 : index + 1; if(index >= 0) { String[] selection = list.getSelection(); Assert.isTrue(selection.length == 1); list.remove(index); list.add(selection[0], target); list.setSelection(target); } selectionChanged(); } /** * Notifies that the Up button has been pressed. */ private void upPressed() { swap(true); } }