How to set up the default value of UI control in WiX?

How can I set the default value of a UI control in WiX installer? When I change the value in the control, the changes are propagated to the property. But I want some sp开发者_JAVA技巧ecific value to be set when the dialog is first displayed.

<?xml version="1.0" encoding="utf-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
  <Fragment>
    <Property Id="PORT" Value="8731" />
    <UI>
      <Dialog Id="MyDialog" Width="370" Height="270" Title="Service protocol configuration">
        <!-- ... -->
        <Control Type="Edit" Id="PortEdit" Width="52" Height="15" X="79" Y="68" Text="8731" Property="PORT" Integer="yes" />
      </Dialog>
    </UI>
  </Fragment>
</Wix>

you may add Indirect="yes" to yout control definition, after that control will display your property's value and all changes to control will change your property immideately.

for example,

  <Dialog Id="InstallDirDlgMine" Width="370" Height="270" Title="!(loc.InstallDirDlgMine_Header)">
...
    <Control Id="Folder" Type="PathEdit" X="135" Y="72" Width="230" Height="20" Property="WIXUI_INSTALLDIR" Indirect="yes" />
...
  </Dialog>

This seemed to work for me (Indirect="yes" didn't work). When that dialog was shown, the control had Show this value in the box as its value.

<?xml version="1.0" encoding="UTF-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
    <Fragment>
    <Property Id="MYPROPERTY" Value="Show this value in the box" />

    <UI>
      <Dialog Id="MyIdDlg" Width="370" Height="270" Title="My Title">
        <!-- omitted --> 
        <Control Id="MyId" Type="Edit" X="20" Y="100" Width="320" Height="18" Property="MYPROPERTY" />
      </Dialog>
    </UI>
    </Fragment>
</Wix>