Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2005 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 *******************************************************************************/ package descent.internal.ui.preferences; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import org.eclipse.core.runtime.CoreException; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.StackLayout; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Label; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.viewers.ComboViewer; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.IStructuredContentProvider; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.StructuredSelection; import org.eclipse.jface.viewers.Viewer; import org.eclipse.jface.text.Assert; import descent.internal.corext.util.Messages; import descent.ui.PreferenceConstants; import descent.ui.text.folding.IJavaFoldingPreferenceBlock; import descent.internal.ui.JavaPlugin; import descent.internal.ui.text.folding.JavaFoldingStructureProviderDescriptor; import descent.internal.ui.text.folding.JavaFoldingStructureProviderRegistry; import descent.internal.ui.util.PixelConverter; /** * Configures Java Editor folding preferences. * * @since 3.0 */ class FoldingConfigurationBlock implements IPreferenceConfigurationBlock { private static class ErrorPreferences implements IJavaFoldingPreferenceBlock { private String fMessage; protected ErrorPreferences(String message) { fMessage = message; } /* * @see descent.internal.ui.text.folding.IJavaFoldingPreferences#createControl(org.eclipse.swt.widgets.Group) */ public Control createControl(Composite composite) { Composite inner = new Composite(composite, SWT.NONE); inner.setLayout(new FillLayout(SWT.VERTICAL)); Label label = new Label(inner, SWT.CENTER); label.setText(fMessage); return inner; } public void initialize() { } public void performOk() { } public void performDefaults() { } public void dispose() { } } /** The overlay preference store. */ private final OverlayPreferenceStore fStore; /* The controls */ private Combo fProviderCombo; private Button fFoldingCheckbox; private ComboViewer fProviderViewer; private Composite fGroup; private StackLayout fStackLayout; /* the model */ private final Map fProviderDescriptors; private final Map fProviderPreferences; private final Map fProviderControls; public FoldingConfigurationBlock(OverlayPreferenceStore store) { Assert.isNotNull(store); fStore = store; fStore.addKeys(createOverlayStoreKeys()); fProviderDescriptors = createListModel(); fProviderPreferences = new HashMap(); fProviderControls = new HashMap(); } private Map createListModel() { JavaFoldingStructureProviderRegistry reg = JavaPlugin.getDefault().getFoldingStructureProviderRegistry(); reg.reloadExtensions(); JavaFoldingStructureProviderDescriptor[] descs = reg.getFoldingProviderDescriptors(); Map map = new HashMap(); for (int i = 0; i < descs.length; i++) { map.put(descs[i].getId(), descs[i]); } return map; } private OverlayPreferenceStore.OverlayKey[] createOverlayStoreKeys() { ArrayList overlayKeys = new ArrayList(); overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, PreferenceConstants.EDITOR_FOLDING_ENABLED)); overlayKeys.add(new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, PreferenceConstants.EDITOR_FOLDING_PROVIDER)); OverlayPreferenceStore.OverlayKey[] keys = new OverlayPreferenceStore.OverlayKey[overlayKeys.size()]; overlayKeys.toArray(keys); return keys; } /** * Creates page for folding preferences. * * @param parent the parent composite * @return the control for the preference page */ public Control createControl(Composite parent) { Composite composite = new Composite(parent, SWT.NULL); // assume parent page uses griddata GridData gd = new GridData(GridData.HORIZONTAL_ALIGN_CENTER | GridData.VERTICAL_ALIGN_FILL); composite.setLayoutData(gd); GridLayout layout = new GridLayout(); layout.numColumns = 2; PixelConverter pc = new PixelConverter(composite); layout.verticalSpacing = pc.convertHeightInCharsToPixels(1) / 2; composite.setLayout(layout); /* check box for new editors */ fFoldingCheckbox = new Button(composite, SWT.CHECK); fFoldingCheckbox.setText(PreferencesMessages.FoldingConfigurationBlock_enable); gd = new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING | GridData.VERTICAL_ALIGN_BEGINNING); fFoldingCheckbox.setLayoutData(gd); fFoldingCheckbox.addSelectionListener(new SelectionListener() { public void widgetSelected(SelectionEvent e) { boolean enabled = fFoldingCheckbox.getSelection(); fStore.setValue(PreferenceConstants.EDITOR_FOLDING_ENABLED, enabled); updateCheckboxDependencies(); } public void widgetDefaultSelected(SelectionEvent e) { } }); Label label = new Label(composite, SWT.CENTER); gd = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_BEGINNING); label.setLayoutData(gd); if (fProviderDescriptors.size() > 1) { /* list */ Composite comboComp = new Composite(composite, SWT.NONE); gd = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_BEGINNING); GridLayout gridLayout = new GridLayout(2, false); gridLayout.marginWidth = 0; comboComp.setLayout(gridLayout); Label comboLabel = new Label(comboComp, SWT.CENTER); gd = new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING | GridData.VERTICAL_ALIGN_CENTER); comboLabel.setLayoutData(gd); comboLabel.setText(PreferencesMessages.FoldingConfigurationBlock_combo_caption); label = new Label(composite, SWT.CENTER); gd = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_BEGINNING); label.setLayoutData(gd); fProviderCombo = new Combo(comboComp, SWT.READ_ONLY | SWT.DROP_DOWN); gd = new GridData(GridData.HORIZONTAL_ALIGN_END | GridData.VERTICAL_ALIGN_CENTER); fProviderCombo.setLayoutData(gd); fProviderViewer = createProviderViewer(); } Composite groupComp = new Composite(composite, SWT.NONE); gd = new GridData(GridData.FILL_BOTH); gd.horizontalSpan = 2; groupComp.setLayoutData(gd); GridLayout gridLayout = new GridLayout(1, false); gridLayout.marginWidth = 0; groupComp.setLayout(gridLayout); /* contributed provider preferences. */ fGroup = new Composite(groupComp, SWT.NONE); gd = new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING | GridData.VERTICAL_ALIGN_BEGINNING); fGroup.setLayoutData(gd); fStackLayout = new StackLayout(); fGroup.setLayout(fStackLayout); return composite; } private ComboViewer createProviderViewer() { /* list viewer */ ComboViewer viewer = new ComboViewer(fProviderCombo); viewer.setContentProvider(new IStructuredContentProvider() { /* * @see org.eclipse.jface.viewers.IContentProvider#dispose() */ public void dispose() { } /* * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object) */ public void inputChanged(Viewer v, Object oldInput, Object newInput) { } /* * @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(java.lang.Object) */ public Object[] getElements(Object inputElement) { return fProviderDescriptors.values().toArray(); } }); viewer.setLabelProvider(new LabelProvider() { /* * @see org.eclipse.jface.viewers.LabelProvider#getImage(java.lang.Object) */ public Image getImage(Object element) { return null; } /* * @see org.eclipse.jface.viewers.LabelProvider#getText(java.lang.Object) */ public String getText(Object element) { return ((JavaFoldingStructureProviderDescriptor) element).getName(); } }); viewer.addSelectionChangedListener(new ISelectionChangedListener() { public void selectionChanged(SelectionChangedEvent event) { IStructuredSelection sel = (IStructuredSelection) event.getSelection(); if (!sel.isEmpty()) { fStore.setValue(PreferenceConstants.EDITOR_FOLDING_PROVIDER, ((JavaFoldingStructureProviderDescriptor) sel.getFirstElement()).getId()); updateListDependencies(); } } }); viewer.setInput(fProviderDescriptors); viewer.refresh(); return viewer; } private void updateCheckboxDependencies() { } void updateListDependencies() { String id = fStore.getString(PreferenceConstants.EDITOR_FOLDING_PROVIDER); JavaFoldingStructureProviderDescriptor desc = (JavaFoldingStructureProviderDescriptor) fProviderDescriptors .get(id); IJavaFoldingPreferenceBlock prefs; if (desc == null) { // safety in case there is no such descriptor String message = Messages.format(PreferencesMessages.FoldingConfigurationBlock_error_not_exist, id); JavaPlugin.log(new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, message, null)); prefs = new ErrorPreferences(message); } else { prefs = (IJavaFoldingPreferenceBlock) fProviderPreferences.get(id); if (prefs == null) { try { prefs = desc.createPreferences(); fProviderPreferences.put(id, prefs); } catch (CoreException e) { JavaPlugin.log(e); prefs = new ErrorPreferences(e.getLocalizedMessage()); } } } Control control = (Control) fProviderControls.get(id); if (control == null) { control = prefs.createControl(fGroup); if (control == null) { String message = PreferencesMessages.FoldingConfigurationBlock_info_no_preferences; control = new ErrorPreferences(message).createControl(fGroup); } else { fProviderControls.put(id, control); } } Dialog.applyDialogFont(control); fStackLayout.topControl = control; control.pack(); fGroup.layout(); fGroup.getParent().layout(); prefs.initialize(); } public void initialize() { restoreFromPreferences(); } public void performOk() { for (Iterator it = fProviderPreferences.values().iterator(); it.hasNext();) { IJavaFoldingPreferenceBlock prefs = (IJavaFoldingPreferenceBlock) it.next(); prefs.performOk(); } } public void performDefaults() { restoreFromPreferences(); for (Iterator it = fProviderPreferences.values().iterator(); it.hasNext();) { IJavaFoldingPreferenceBlock prefs = (IJavaFoldingPreferenceBlock) it.next(); prefs.performDefaults(); } } public void dispose() { for (Iterator it = fProviderPreferences.values().iterator(); it.hasNext();) { IJavaFoldingPreferenceBlock prefs = (IJavaFoldingPreferenceBlock) it.next(); prefs.dispose(); } } private void restoreFromPreferences() { boolean enabled = fStore.getBoolean(PreferenceConstants.EDITOR_FOLDING_ENABLED); fFoldingCheckbox.setSelection(enabled); updateCheckboxDependencies(); String id = fStore.getString(PreferenceConstants.EDITOR_FOLDING_PROVIDER); Object provider = fProviderDescriptors.get(id); // Fallback to default if (provider == null) { String message = Messages.format( PreferencesMessages.FoldingConfigurationBlock_warning_providerNotFound_resetToDefault, id); JavaPlugin.log(new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, message, null)); id = JavaPlugin.getDefault().getPreferenceStore() .getDefaultString(PreferenceConstants.EDITOR_FOLDING_PROVIDER); provider = fProviderDescriptors.get(id); /* * In 3.2.1 we don't want to risk anything, hence don't * Assert.isNotNull(provider); */ if (provider == null) return; fStore.setToDefault(PreferenceConstants.EDITOR_FOLDING_PROVIDER); } if (fProviderViewer == null) updateListDependencies(); else fProviderViewer.setSelection(new StructuredSelection(provider), true); } }