no RadioButtonCell in GWT 2.4 Cell?

[peter tong]

I check the GWT 2.4 API
Cell
and found there is no RadioButtonCell, so if I need a column with radio button on each row, how to do it using GWT 2.4?

[Harendra Kumar]

You can write your custom RadioCell by extending CheckboxCell class and override render() method.

[peter tong]

Harendra Kumar wrote:You can write your custom RadioCell by extending CheckboxCell class and override render() method.

override this method
public void render(Cell.Context context,
java.lang.Boolean value,
SafeHtmlBuilder sb)
?

how to start?

[Maneesh Godbole]

Recommended reading http://code.google.com/webtoolkit/doc/latest/DevGuideUiCellWidgets.html

[peter tong]

I extends the CheckboxCell.class as follow:

public class RadioCell extends CheckboxCell {
	
	 /**
	   * An html string representation of a checked input box.
	   */
	  private static final SafeHtml INPUT_SELECTED = SafeHtmlUtils.fromSafeConstant("<input type=\"radio\" name=\"selected\" tabindex=\"-1\" checked/>");
	  private static final SafeHtml INPUT_UNCHECKED = SafeHtmlUtils.fromSafeConstant("<input type=\"radio\" name=\"selected\" tabindex=\"-1\"/>");
	  @Override
	  public void render(Context context, Boolean value, SafeHtmlBuilder sb) {
	    // Get the view data.
	    Object key = context.getKey();
	    Boolean viewData = getViewData(key); 
	   
	    
	    if (value != null && value) {
	      sb.append(INPUT_SELECTED);
	    } else{
	    	sb.append(INPUT_UNCHECKED);
	    }
	  }

}

everything seems ok, but now I want to add a button, and when press that button, it will give me the selected record information, I try to use singleselectionmodel as follow:

final SingleSelectionModel<Log> singleSelectionModel = new SingleSelectionModel<Log>(keyProvider);
singleSelectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler(){
	@Override
	public void onSelectionChange(SelectionChangeEvent event) {
		// TODO Auto-generated method stub
		singleSelectionModel.setSelected(singleSelectionModel.getSelectedObject(), true);
		table.redraw();
	}});

table.setSelectionModel(singleSelectionModel);

but now a very strange thing occur, when I select a radiobutton in a row of the table, the radio button will not selected, I need press the radio button once more to get it selected, before adding the singleselectionmodel,
no this problem occur!!

[peter tong]

singleSelectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler(){  
    @Override  
    public void onSelectionChange(SelectionChangeEvent event) {  
        // TODO Auto-generated method stub  
        singleSelectionModel.setSelected(singleSelectionModel.getSelectedObject(), true);  
        table.redraw();  
    }}); 

is there a way to locate the previous selected object so I can set its value to false?
I found that although I set the selected object to true, but the previous selected object is also true, and seems there is no method in onSelectionChange event to get the previous selected object, any method?

[peter tong]

really need help, maybe I simplify what I want to do.
there is a celltable with a column of radio button for each row, user can select a row using that radio button, and click a button outside the celltable to open the detail page for that row.
the requirement is easy, but I really do not know how to do it.