org.eclipse.core.runtime.AssertionFailedException: assertion failed: - swt

Question

I am trying to create a table with ComboBoxCellEditor column. When I set value that time below exception is coming.
import org.eclipse.jface.util.Policy;
import org.eclipse.jface.viewers.*;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;
/............/
public class Test {
public static void main(String[] args) {
Shell shell = new Shell();
shell.setText("TableViewer Example");
GridLayout layout = new GridLayout();
shell.setLayout(layout);
Composite composite = new Composite(shell, SWT.NONE);
composite.setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, true));
composite.setLayout(new GridLayout(1, false));
Table testTable = new Table(composite, SWT.BORDER);
testTable.setLinesVisible(true);
testTable.setHeaderVisible(true);
GridData tableData = new GridData(SWT.FILL, SWT.FILL, true, false);
tableData.heightHint = 300;
testTable.setLayoutData(tableData);
TableViewerColumn columnViewer = null;
String[] columnNames = { "Name", "Laptops" };
TableViewer testTableViewer = new TableViewer(testTable);
for (int i = 0; i < columnNames.length; i++) {
columnViewer = new TableViewerColumn(testTableViewer, SWT.LEFT);
columnViewer.getColumn().setText(columnNames[i]);
if (columnNames[i].equals("Name")) {
columnViewer.getColumn().setWidth(200);
} else if (columnNames[i].equals("Laptops")) {
columnViewer.getColumn().setWidth(300);
}
columnViewer.getColumn().setResizable(true);
columnViewer.getColumn().setMoveable(true);
columnViewer.setLabelProvider(new TestColumnLabelProvider(i));
}
testTableViewer.setContentProvider(new TestContentProvider());
testTableViewer.setColumnProperties(columnNames);
TestBean[] testBeans = new TestBean[5];
for (int i = 0; i < 5; i++) {
TestBean bean = new TestBean();
TableViewerColumn[] getTableViewerColumns =
getTableViewerColumns(testTableViewer);
for (int j = 0; j < getTableViewerColumns.length; j++) {
getTableViewerColumns[j].setEditingSupport(new
TestEditingSuport(testTableViewer, j, bean.getListOfLaptop));
}
bean.setName("Debasish" + i);
bean.setLaptop(bean.getListOfLaptop[i]);
testBeans[i] = bean;
}
testTableViewer.setInput(testBeans);
shell.open();
Display display = shell.getDisplay();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
}
public static TableViewerColumn[] getTableViewerColumns(TableViewer
tableViewer) {
TableColumn[] columns = tableViewer.getTable().getColumns();
TableViewerColumn[] viewerColumns = new TableViewerColumn[columns.length];
for (int i = 0; i < columns.length; i++) {
TableColumn tableColumn = columns[i];
viewerColumns[i] = (TableViewerColumn) tableColumn.getData(Policy.JFACE +
".columnViewer");
}
return viewerColumns;
}
}
/............./
class TestBean {
private String name;
private String laptop;
public String[] getListOfLaptop = { "Acer", "HP", "Lenovo", "Dell", "Benq"
};
//getter and setter method
}
/..................../
class TestEditingSuport extends EditingSupport {
private int m_column;
private CellEditor m_editor;
public TestEditingSuport(ColumnViewer viewer, int column,
String[] listOfTestBean) {
super(viewer);
m_column = column;
// Create the correct editor based on the column index
switch (column) {
case 0:
case 1:
m_editor = new ComboBoxCellEditor(
((TableViewer) viewer).getTable(), listOfTestBean);
break;
default:
}
}
#Override
protected CellEditor getCellEditor(Object element) {
return m_editor;
}
#Override
protected boolean canEdit(Object element) {
return true;
}
#Override
protected Object getValue(Object element) {
TestBean bean = (TestBean) element;
Object value = null;
switch (m_column) {
case 0:
value = bean.getName();
break;
case 1:
value = bean.getLaptop();
break;
default:
}
return value;
}
#Override
protected void setValue(Object element, Object value) {
TestBean bean = (TestBean) element;
switch (m_column) {
case 0:
if (valueChanged(bean.getName(), (String) value)) {
bean.setName((String) value);
}
getViewer().update(bean, null);
break;
case 1:
int index = (Integer) value;
String laptop = bean.getListOfLaptop[index];
if (valueChanged(bean.getLaptop(), laptop)) {
bean.setLaptop(laptop);
}
getViewer().update(bean, null);
break;
default:
}
}
private boolean valueChanged(String previousValue, String currentValue) {
boolean changed = false;
if ((previousValue == null) && (currentValue != null)) {
changed = true;
} else if ((previousValue != null) && (currentValue != null) && (!previousValue.equals(currentValue))) {
changed = true;
}
return changed;
}
}
/............../
class TestContentProvider implements IStructuredContentProvider {
#Override
public Object[] getElements(Object inputElement) {
return (Object[]) inputElement;
}
}
/........................./
class TestColumnLabelProvider extends ColumnLabelProvider {
private int m_column;
public TestColumnLabelProvider(int column) {
this.m_column = column;
}
public String getText(Object element) {
String text = null;
if (element instanceof TestBean) {
TestBean testBean = (TestBean) element;
switch (m_column) {
case 0:
text = testBean.getName();
break;
case 1:
text = testBean.getLaptop();
break;
default:
}
}
return text;
}
}
/....................../

Answer 1

ComboCellEditor values are integer indexes in to the list of values you give it in the constructor.
Your getValue method of your EditingSupport class must return an Integer index in to the values list.
The setValue method of your EditingSupport class will be given an Integer containing the selected index.