provide variant of report view that shows results only after query parameters have been entered

expert/browser/report.pt

@@ -5,8 +5,28 @@
   <div tal:define="report item/reportInstance;
                    reportView nocall:item"
        tal:attributes="class string:content-$level;">
+    <div metal:use-macro="item/report_macros/header" />
+    <div metal:use-macro="item/resultsRenderer" />
+  </div>
+</div>
+
+
+<div metal:define-macro="main_params">
+  <div tal:define="report item/reportInstance;
+                   reportView nocall:item"
+       tal:attributes="class string:content-$level;">
+    <div metal:use-macro="item/report_macros/header" />
+    <tal:results condition="request/show_results|nothing">
+      <div metal:use-macro="item/resultsRenderer" />
+    </tal:results>
+  </div>
+</div>
+
+
+<div metal:define-macro="header">
       <metal:block use-macro="view/concept_macros/concepttitle" />
       <form method="post" name="report_data" class="report-meta">
+        <input type="hidden" name="show_results" value="True" />
         <tal:hidden define="params item/dynamicParams"
                     tal:condition="nothing">
           <input type="hidden"
@@ -26,8 +46,6 @@
         </div>
         <br />
       </form>
-    <div metal:use-macro="item/resultsRenderer" />
-  </div>
 </div>
 
 

expert/browser/report.py

@@ -226,3 +226,12 @@ class ReportConceptView(ResultsConceptView, ReportView):
         if ri.userSettings:
             return [f for f in qf if f in ri.userSettings]
         return qf
+
+
+class ReportParamsView(ReportConceptView):
+    """ Report view allowing to enter parameters before executing the report.
+    """
+
+    @Lazy
+    def macro(self):
+        return self.report_macros['main_params']