You could use some JavaScript like this on the OnChange event of the boolean field:
function OnChange() {
if (Xrm.Page.getAttribute("new_bool").getValue() === true) {
Xrm.Page.getControl("new_date").setVisible(true);
Xrm.Page.getAttribute("new_date").setValue(new Date());
} else {
Xrm.Page.getControl("new_date").setVisible(false);
Xrm.Page.getAttribute("new_date").setValue(null);
}
}
Jason Lattimer
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