Default option in SelectionCell - gwt

Question

When I pass a string list to selectionCell, the first element will be choosen as a default value, how can I change the default value? For example at runtime I want to see the item at index=i as a default value.

Answer 1

There is no way to set an index in that cell
You can use only String there
SelectionCell statusOptionsCell = new SelectionCell(statusType);
Column<InvitedUser, String> statusColumn = new Column<Object, String>(
statusOptionsCell) {
#Override
public String getValue(Object object) {
return object.getStatus(); //value set at runtime
}
};
And if you need array only then
String[] myaaray= {"one","two","three"};
SelectionCell statusOptionsCell = new SelectionCell(statusType);
Column<InvitedUser, String> statusColumn = new Column<Object, String>(
statusOptionsCell) {
#Override
public String getValue(Object object) {
return st[1]; //pass integer as i here at runtime
}
};

Answer 2

Selection Cells are used in Cell widgets. So lets take CellTable as an example. In a Cell Table each row corresponds to one record ie a model/POJO. Each column corresponds to one property in the model/POJO. So, your selection cell column should be bound to one property in the model.
Set that property's value to whatever you want as a default value before supplying that model to the Cell Table.
Once you set the model's property its all Cell table and co's responsibility to set the value in to the selection cell.

Answer 3

I have a real-life example of changing SelectionCell's value at runtime. I want to have a list of possible actions to be performed for each row. After selecting (and performing) an action I want the select to be set back to it's default value.
ArrayList<String> options = new ArrayList<String>();
options.add("Choose...");
options.add("Action 1");
options.add("Action 2");
final SelectionCell cell = new SelectionCell(options);
Column<MyObject, String> column = new Column<MyObject, String>(cell) {
#Override
public String getValue(MyObject object) {
return null;
}
};
column.setFieldUpdater(new FieldUpdater<MyObject, String>() {
#Override
public void update(final int index, MyObject object, String value) {
// perform selected action
// action name is stored in the `value` parameter
// ...
// back to default value
cell.clearViewData(object);
// ... or back to other value
// cell.setViewData(object, "Action 1");
table.redrawRow(index);
}
});
table.addColumn(column, "Test");
Notice that the action is hooked-up on update method so it will be fired only if selected value has changed. It will never be fired with default value ("Choose...").