Java tutorial
/******************************************************************************* * Copyright (c) 2003, 2010 Berthold Daum and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Common Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/cpl-v10.html * * Contributors: * Berthold Daum *******************************************************************************/ package org.eclipse.cdt.codan.internal.ui.preferences; import java.util.ArrayList; import java.util.List; import org.eclipse.cdt.codan.core.CodanCorePlugin; import org.eclipse.cdt.codan.core.PreferenceConstants; import org.eclipse.cdt.codan.internal.ui.CodanUIActivator; import org.eclipse.cdt.codan.internal.ui.CodanUIMessages; import org.eclipse.core.resources.IProject; import org.eclipse.core.resources.ProjectScope; import org.eclipse.core.runtime.IAdaptable; import org.eclipse.core.runtime.preferences.IScopeContext; import org.eclipse.core.runtime.preferences.InstanceScope; import org.eclipse.jface.preference.FieldEditor; import org.eclipse.jface.preference.FieldEditorPreferencePage; import org.eclipse.jface.preference.IPreferenceNode; import org.eclipse.jface.preference.IPreferencePage; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.PreferenceDialog; import org.eclipse.jface.preference.PreferenceManager; import org.eclipse.jface.preference.PreferenceNode; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.BusyIndicator; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; 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.ui.IWorkbenchPropertyPage; import org.eclipse.ui.preferences.ScopedPreferenceStore; /** * @author Berthold Daum */ public abstract class FieldEditorOverlayPage extends FieldEditorPreferencePage implements IWorkbenchPropertyPage { // Stores all created field editors private List<FieldEditor> editors = new ArrayList<FieldEditor>(); // Stores owning element of properties private IAdaptable element; // Additional buttons for property pages private Button useWorkspaceSettingsButton, useProjectSettingsButton, configureButton; // Overlay preference store for property pages private IPreferenceStore overlayStore; // The image descriptor of this pages title image private ImageDescriptor image; // Cache for page id private String pageId; /** * Constructor * * @param style * - layout style */ public FieldEditorOverlayPage(int style) { super(style); } /** * Constructor * * @param title * - title string * @param style * - layout style */ public FieldEditorOverlayPage(String title, int style) { super(title, style); } /** * Constructor * * @param title * - title string * @param image * - title image * @param style * - layout style */ public FieldEditorOverlayPage(String title, ImageDescriptor image, int style) { super(title, image, style); this.image = image; } /** * Returns the id of the current preference page as defined in plugin.xml * Subclasses must implement. * * @return - the qualifier */ protected abstract String getPageId(); /** * Receives the object that owns the properties shown in this property page. * * @see org.eclipse.ui.IWorkbenchPropertyPage#setElement(org.eclipse.core.runtime.IAdaptable) */ @Override public void setElement(IAdaptable element) { this.element = element; } /** * Delivers the object that owns the properties shown in this property page. * * @see org.eclipse.ui.IWorkbenchPropertyPage#getElement() */ @Override public IAdaptable getElement() { if (element == null) return element; if (!(element instanceof IProject)) return (IAdaptable) element.getAdapter(IProject.class); return element; } /** * Returns true if this instance represents a property page * * @return - true for property pages, false for preference pages */ public boolean isPropertyPage() { return getElement() != null; } /** * We override the addField method. This allows us to store each field * editor added by subclasses in a list for later processing. * * @see org.eclipse.jface.preference.FieldEditorPreferencePage#addField(org.eclipse.jface.preference.FieldEditor) */ @Override protected void addField(FieldEditor editor) { editors.add(editor); super.addField(editor); } /** * We override the createControl method. In case of property pages we create * a new PropertyStore as local preference store. After all control have * been create, we enable/disable these controls. * * @see org.eclipse.jface.preference.PreferencePage#createControl(Composite) */ @Override public void createControl(Composite parent) { // Special treatment for property pages if (isPropertyPage()) { // Cache the page id pageId = getPageId(); // Create an overlay preference store and fill it with properties IAdaptable e = getElement(); if (e != null) { ProjectScope ps = new ProjectScope((IProject) e); ScopedPreferenceStore scoped = new ScopedPreferenceStore(ps, CodanCorePlugin.PLUGIN_ID); scoped.setSearchContexts(new IScopeContext[] { ps, InstanceScope.INSTANCE }); overlayStore = scoped; } // Set overlay store as current preference store } super.createControl(parent); // Update state of all subclass controls if (isPropertyPage()) updateFieldEditors(); } /** * We override the createContents method. In case of property pages we * insert two radio buttons at the top of the page. * * @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite) */ @Override protected Control createContents(Composite parent) { if (isPropertyPage()) createSelectionGroup(parent); return super.createContents(parent); } /** * Creates and initializes a selection group with two choice buttons and one * push button. * * @param parent * - the parent composite */ private void createSelectionGroup(Composite parent) { Composite comp = new Composite(parent, SWT.NONE); GridLayout layout = new GridLayout(2, false); layout.marginHeight = 0; layout.marginWidth = 0; comp.setLayout(layout); comp.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); Composite radioGroup = new Composite(comp, SWT.NONE); radioGroup.setLayout(new GridLayout()); radioGroup.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); useWorkspaceSettingsButton = createRadioButton(radioGroup, CodanUIMessages.OverlayPage_Use_Workspace_Settings); useProjectSettingsButton = createRadioButton(radioGroup, CodanUIMessages.OverlayPage_Use_Project_Settings); configureButton = new Button(comp, SWT.PUSH); configureButton.setText(CodanUIMessages.OverlayPage_Configure_Workspace_Settings); configureButton.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { configureWorkspaceSettings(); } }); // Set workspace/project radio buttons try { IPreferenceStore preferences = getPreferenceStore(); if (!preferences.contains(PreferenceConstants.P_USE_PARENT) || preferences.getBoolean(PreferenceConstants.P_USE_PARENT)) { useWorkspaceSettingsButton.setSelection(true); } else { useProjectSettingsButton.setSelection(true); configureButton.setEnabled(false); } } catch (Exception e) { useWorkspaceSettingsButton.setSelection(true); } } /** * Convenience method creating a radio button * * @param parent * - the parent composite * @param label * - the button label * @return - the new button */ private Button createRadioButton(Composite parent, String label) { final Button button = new Button(parent, SWT.RADIO); button.setText(label); button.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { configureButton.setEnabled(button == useWorkspaceSettingsButton); updateFieldEditors(); } }); return button; } /** * Returns in case of property pages the overlay store, in case of * preference pages the standard preference store * * @see org.eclipse.jface.preference.PreferencePage#getPreferenceStore() */ @Override public IPreferenceStore getPreferenceStore() { if (isPropertyPage()) return overlayStore; return super.getPreferenceStore(); } /** * Enables or disables the field editors and buttons of this page */ private void updateFieldEditors() { // We iterate through all field editors boolean enabled = useProjectSettingsButton.getSelection(); updateFieldEditors(enabled); } /** * Enables or disables the field editors and buttons of this page Subclasses * may override. * * @param enabled * - true if enabled */ protected void updateFieldEditors(boolean enabled) { Composite parent = getFieldEditorParent(); for (FieldEditor editor : editors) { editor.setEnabled(enabled, parent); } } /** * We override the performOk method. In case of property pages we copy * the values in the overlay store into the property values of the selected * project. We also save the state of the radio buttons. * * @see org.eclipse.jface.preference.IPreferencePage#performOk() */ @Override public boolean performOk() { boolean result = super.performOk(); if (result && isPropertyPage()) { // Save state of radio buttons in project properties getPreferenceStore().setValue(PreferenceConstants.P_USE_PARENT, useWorkspaceSettingsButton.getSelection()); } return result; } /** * We override the performDefaults method. In case of property pages we * switch back to the workspace settings and disable the field editors. * * @see org.eclipse.jface.preference.PreferencePage#performDefaults() */ @Override protected void performDefaults() { if (isPropertyPage()) { useWorkspaceSettingsButton.setSelection(true); useProjectSettingsButton.setSelection(false); configureButton.setEnabled(true); updateFieldEditors(); } super.performDefaults(); } /** * Creates a new preferences page and opens it */ @SuppressWarnings("cast") protected void configureWorkspaceSettings() { try { // create a new instance of the current class IPreferencePage page = (IPreferencePage) this.getClass().newInstance(); page.setTitle(getTitle()); page.setImageDescriptor(image); // and show it showPreferencePage(pageId, page); } catch (InstantiationException e) { CodanUIActivator.log(e); } catch (IllegalAccessException e) { CodanUIActivator.log(e); } } /** * Show a single preference pages * * @param id * - the preference page identification * @param page * - the preference page */ protected void showPreferencePage(String id, IPreferencePage page) { final IPreferenceNode targetNode = new PreferenceNode(id, page); PreferenceManager manager = new PreferenceManager(); manager.addToRoot(targetNode); final PreferenceDialog dialog = new PreferenceDialog(getControl().getShell(), manager); BusyIndicator.showWhile(getControl().getDisplay(), new Runnable() { @Override public void run() { dialog.create(); dialog.setMessage(targetNode.getLabelText()); dialog.open(); } }); } }