/*******************************************************************************
* Copyright (c) 2000, 2015 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
* Sergey Prigogin (Google)
*******************************************************************************/
package org.eclipse.cdt.codan.internal.ui.preferences;
import org.eclipse.cdt.codan.internal.ui.CodanUIMessages;
import org.eclipse.jface.preference.FieldEditor;
import org.eclipse.jface.viewers.CheckStateChangedEvent;
import org.eclipse.jface.viewers.CheckboxTreeViewer;
import org.eclipse.jface.viewers.ICheckStateListener;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.StructuredViewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
/**
* An abstract field editor that manages a checked tree. Values in the tree
* should be set outside by setting getTreeViewer().setContentProvider() and
* getTreeViewer().setInput() Control stores checked elements only in preference
* storage.
*
* <p>
* Subclasses may implement the <code>parseString</code>,
* <code>createList</code>, <code>storeValue</code> and
* <code>getListSeparator</code> framework methods.
* </p>
*/
public abstract class CheckedTreeEditor extends FieldEditor implements ICheckStateListener {
/**
* The list widget; <code>null</code> if none (before creation or after disposal).
*/
private CheckboxTreeViewer treeViewer;
private Composite listParent;
private boolean isValid;
private boolean emptySelectionAllowed;
/**
* Creates a new list field editor
*/
protected CheckedTreeEditor() {
}
/**
* 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
*/
public CheckedTreeEditor(String name, String labelText, Composite parent) {
init(name, labelText);
createControl(parent);
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void adjustForNumColumns(int numColumns) {
Control control = getLabelControl();
if (control != null) {
((GridData) control.getLayoutData()).horizontalSpan = numColumns;
((GridData) getTreeControl().getLayoutData()).horizontalSpan = numColumns;
} else {
((GridData) getTreeControl().getLayoutData()).horizontalSpan = numColumns;
}
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void doFillIntoGrid(Composite parent, int numColumns) {
doFillLabelIntoGrid(parent, numColumns);
doFillBoxIntoGrid(parent, numColumns);
}
protected void doFillLabelIntoGrid(Composite parent, int numColumns) {
String text = getLabelText();
if (text != null && text.length() > 0) {
Control control = getLabelControl(parent);
GridData gd = new GridData();
gd.horizontalSpan = numColumns;
control.setLayoutData(gd);
}
}
protected void doFillBoxIntoGrid(Composite parent, int numColumns) {
GridData gd;
Control list = createListControl(parent);
gd = new GridData(GridData.FILL_HORIZONTAL);
gd.verticalAlignment = GridData.FILL;
gd.horizontalSpan = numColumns;
gd.grabExcessHorizontalSpace = true;
gd.grabExcessVerticalSpace = true;
list.setLayoutData(gd);
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void doLoad() {
if (getTreeControl() != null) {
String s = getPreferenceStore().getString(getPreferenceName());
getViewer().setInput(modelFromString(s));
}
}
protected abstract Object modelFromString(String s);
Control getTreeControl() {
if (treeViewer == null)
return null;
return treeViewer.getControl();
}
public CheckboxTreeViewer getTreeViewer() {
return treeViewer;
}
/**
* @Override
* @see org.eclipse.jface.viewers.ICheckStateListener#checkStateChanged(org.eclipse.jface.viewers.CheckStateChangedEvent)
*/
@Override
public void checkStateChanged(CheckStateChangedEvent event) {
Object element = event.getElement();
treeViewer.setGrayed(element, false);
treeViewer.setSubtreeChecked(element, event.getChecked());
Object parent = getContentProvider().getParent(element);
if (parent != null) {
updateCheckedState(parent);
treeViewer.setParentsGrayed(parent, true);
}
refreshValidState();
}
private ITreeContentProvider getContentProvider() {
return ((ITreeContentProvider) treeViewer.getContentProvider());
}
private void updateCheckedState(Object parent) {
Object[] children = getContentProvider().getChildren(parent);
int i, count = 0;
for (i = 0; i < children.length; i++) {
Object object = children[i];
if (treeViewer.getChecked(object)) {
count++;
}
}
if (count > 0) {
treeViewer.setChecked(parent, true);
}
if (count == 0) {
treeViewer.setGrayed(parent, false);
treeViewer.setChecked(parent, false);
return;
}
if (count < i) {
treeViewer.setGrayed(parent, true);
}
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void doLoadDefault() {
if (getTreeControl() != null) {
String s = getPreferenceStore().getDefaultString(getPreferenceName());
getViewer().setInput(modelFromString(s));
}
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void doStore() {
String s = modelToString(getViewer().getInput());
if (s != null) {
getPreferenceStore().setValue(getPreferenceName(), s);
}
}
/**
* Returns this field editor's list control.
*
* @param parent
* the parent control
* @return the list control
*/
public Tree createListControl(Composite parent) {
Tree table = (Tree) getTreeControl();
if (table == null) {
listParent = parent;
treeViewer = doCreateTreeViewer(parent, SWT.BORDER | SWT.MULTI | SWT.V_SCROLL | SWT.H_SCROLL | SWT.FULL_SELECTION);
table = treeViewer.getTree();
table.setFont(parent.getFont());
treeViewer.setComparator(new ViewerComparator());
treeViewer.addCheckStateListener(this);
}
return table;
}
protected CheckboxTreeViewer doCreateTreeViewer(Composite parent, int style) {
return new CheckboxTreeViewer(parent, style);
}
public StructuredViewer getViewer() {
return treeViewer;
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
public int getNumberOfControls() {
return 2;
}
/**
* 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() {
return treeViewer.getControl().getShell();
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
public void setFocus() {
if (getTreeControl() != null) {
getTreeControl().setFocus();
}
}
/*
* @see FieldEditor.setEnabled(boolean,Composite).
*/
@Override
public void setEnabled(boolean enabled, Composite parent) {
super.setEnabled(enabled, parent);
createListControl(parent).setEnabled(enabled);
}
/**
* Combines the given list of items into a single string. This method is the
* converse of <code>parseString</code>.
* <p>
* Subclasses may implement this method.
* </p>
*
* @return the combined string
* @see #modelFromString(String)
*/
protected abstract String modelToString(Object model);
@Override
protected void createControl(Composite parent) {
GridLayout ly = (GridLayout) parent.getLayout();
doFillIntoGrid(parent, ly.numColumns);
}
/**
* @param b
*/
public void setEnabled(boolean b) {
setEnabled(b, listParent);
}
public Composite getTreeParent() {
return listParent;
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
public boolean isValid() {
return isValid;
}
/*
* (non-Javadoc) Method declared on FieldEditor.
*/
@Override
protected void refreshValidState() {
isValid = checkState();
}
protected boolean checkState() {
if (!emptySelectionAllowed) {
Object[] checkedElements = getTreeViewer().getCheckedElements();
if (checkedElements.length == 0) {
showErrorMessage(CodanUIMessages.CheckedTreeEditor_SelectionCannotBeEmpty);
return false;
}
}
clearErrorMessage();
return true;
}
public final boolean isEmptySelectionAllowed() {
return emptySelectionAllowed;
}
public final void setEmptySelectionAllowed(boolean emptySelectionAllowed) {
this.emptySelectionAllowed = emptySelectionAllowed;
}
}