In my previous post I built a rule that would hide a component based on some criterias regarding the datasource item. In the Page Editor these hidden component would show as grey blocks which is nice since you get a clear indication that there’s a component and that it isn’t translated. But now what? A natural next step would be to be able to add a version of that component to be able to translate it.
My main idea was to add a button to the component in the page editor, visible when the component was greyed out. When clicked would add a version in the current language of the related item.
As I didn’t realy know if things would work or not, my approach was kind of touch and go. My first goal was to add a button when the component was hidden (greyed out). On a rendering you can add additional buttons visible for that component when in the Page Editor using the Page Editor Buttons. However once a rendering is hidden it will be switched in the Page Editor to another rendering and all the configured Page Editor Buttons would disappear. You could probably add buttons to the Hidden Rendering which will replace the original rendering, but I didn’t have that in mind at the time 
I went with adding a Default Rendering Button, which is located here in the Core database /sitecore/content/Applications/WebEdit/Default Rendering Buttons/. This is where all default buttons for a component is located such as the Edit Related item, Change Position and so on. So I created a button.
Then I created a class inheriting the WebEditCommand. I didn’t know what to expect when the button executed the command. If I would get the datasouce item out of the box or if I would have to manually find it in some way. But it turned out to be quit easy. If the rendering had no datasource configured the CommandContext object passed to the command would give the current item and if the datasource was set it would pass that item instead. Since this was a default rendering button, it would be visible for all renderings all the time. So I had to override the QueryState and write my own to hide the button if the item had a version. Below is the resulting command:
public class AddDatasourceVersion : WebEditCommand
{
public override void Execute(CommandContext context)
{
Assert.ArgumentNotNull((object)context, "context");
Item obj = context.Items[0];
if (obj.Versions.Count > 0) return;
using (new SecurityDisabler())
{
obj.Versions.AddVersion();
}
}
public override CommandState QueryState(CommandContext context)
{
Assert.ArgumentNotNull((object)context, "context");
Item obj = context.Items[0];
return obj.Versions.Count > 0 ? CommandState.Hidden : CommandState.Enabled;
}
}
A command was defined and configured for the button, I went with:
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:set="http://www.sitecore.net/xmlconfig/set/">
<sitecore>
<commands>
<command name="custom:adddatasourceversion" type="Lab.Sample.Commands.WebEdit.AddDatasourceVersion,Lab.Sample"/>
</commands>
</sitecore>
</configuration>
A recommendation though! For best user experience, use Standard Values with prefilled dummy data, because it can be hard to find the component once a version has been added if there is no content or any obvious graphical elements 
