Merge pull request #591 from neilsb/add-screen-events

components/JFScreen.brs

@@ -0,0 +1,16 @@
+' Function called when the screen is displayed by the screen manager
+' It is expected that screens override this function to handle focus
+' managmenet and any other actions required on screen shown
+sub OnScreenShown()
+    if m.top.lastFocus <> invalid
+        m.top.lastFocus.setFocus(true)
+    else
+        m.top.setFocus(true)
+    end if
+end sub
+
+' Function called when the screen is hidden by the screen manager
+' It is expected that screens override this function if required,
+' to handle focus any actions required on the screen being hidden
+sub OnScreenHidden()
+end sub

components/JFScreen.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<component name="JFScreen" extends="JFGroup">
+  <interface>
+    <function name="OnScreenShown" />
+    <function name="OnScreenHidden" />
+  </interface>
+  <script type="text/brightscript" uri="JFScreen.brs" />
+</component>

components/data/SceneManager.brs

@@ -28,6 +28,11 @@ sub pushScene(newGroup)
         end if
 
         currentGroup.visible = false
+
+        if currentGroup.isSubType("JFScreen")
+            currentGroup.callFunc("OnScreenHidden")
+        end if
+
     end if
 
     m.groups.push(newGroup)
@@ -38,6 +43,10 @@ sub pushScene(newGroup)
         m.content.appendChild(newGroup)
     end if
 
+    if newGroup.isSubType("JFScreen")
+        newGroup.callFunc("OnScreenShown")
+    end if
+
     'observe info about new group, set overhang title, etc.
     if newGroup.isSubType("JFGroup")
         registerOverhangData(newGroup)
@@ -65,6 +74,12 @@ sub popScene()
             ' Stop video to make sure app communicates stop playstate to server
             group.control = "stop"
         end if
+
+        group.visible = false
+
+        if group.isSubType("JFScreen")
+            group.callFunc("OnScreenHidden")
+        end if
     else
         ' Exit app if for some reason we don't have anything on the stack
         m.scene.exit = true
@@ -86,11 +101,16 @@ sub popScene()
 
         m.content.replaceChild(group, 0)
 
-        ' Restore focus
-        if group.lastFocus <> invalid
-            group.lastFocus.setFocus(true)
+        if group.isSubType("JFScreen")
+            group.callFunc("OnScreenShown")
         else
-            group.setFocus(true)
+
+            ' Restore focus
+            if group.lastFocus <> invalid
+                group.lastFocus.setFocus(true)
+            else
+                group.setFocus(true)
+            end if
         end if
     else
         ' Exit app if the stack is empty after removing group

components/movies/MovieDetails.brs

@@ -14,10 +14,17 @@ sub init()
 
     m.buttonGrp = m.top.findNode("buttons")
     m.buttonGrp.setFocus(true)
+    m.top.lastFocus = m.buttonGrp
 
     m.top.observeField("itemContent", "itemContentChanged")
 end sub
 
+sub OnScreenShown()
+    ' set focus to button group
+    m.buttonGrp.setFocus(true)
+end sub
+
+
 sub itemContentChanged()
     ' Updates video metadata
     item = m.top.itemContent

components/movies/MovieDetails.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8" ?>
-<component name="MovieDetails" extends="JFGroup">
+<component name="MovieDetails" extends="JFScreen">
   <children>
     <LayoutGroup id="main_group" layoutDirection="horiz" itemSpacings="[30]">
       <Poster id="moviePoster"

source/Main.brs

@@ -231,6 +231,10 @@ sub Main (args as dynamic) as void
                 if video <> invalid
                     sceneManager.callFunc("pushScene", video)
                 end if
+
+                if group.lastFocus <> invalid
+                    group.lastFocus.setFocus(true)
+                end if
             else if btn <> invalid and btn.id = "watched-button"
                 movie = group.itemContent
                 if movie.watched