diff --git a/applet.cpp b/applet.cpp
index 925124b11..f5a599be9 100644
--- a/applet.cpp
+++ b/applet.cpp
@@ -474,15 +474,15 @@ const Package* Applet::package() const
     return d->package;
 }
 
-void Applet::updateConstraints()
+void Applet::updateConstraints(Plasma::Constraints constraints)
 {
-    constraintsUpdated();
+    constraintsUpdated(constraints);
     setShadowShown(formFactor() == Planar);
 }
 
-void Applet::constraintsUpdated()
+void Applet::constraintsUpdated(Plasma::Constraints constraints)
 {
-    kDebug() << "Applet::constraintsUpdate(): constraints are FormFactor: " << formFactor() << ", Location: " << location();
+    kDebug() << constraints << "constraints are FormFactor: " << formFactor() << ", Location: " << location();
 }
 
 QString Applet::name() const
diff --git a/applet.h b/applet.h
index 4e734b574..e0582cd44 100644
--- a/applet.h
+++ b/applet.h
@@ -182,8 +182,10 @@ class PLASMA_EXPORT Applet : public Widget
          * Called when any of the geometry constraints have been updated.
          * This method calls constraintsUpdated, which may be reimplemented,
          * once the Applet has been prepared for updating the constraints.
+         *
+         * @param constraints the type of constraints that were updated
          */
-        void updateConstraints();
+        void updateConstraints(Plasma::Constraints constraints);
 
         /**
          * Called when any of the geometry constraints have been updated.
@@ -194,9 +196,10 @@ class PLASMA_EXPORT Applet : public Widget
          * Do not call update() from this method; an update() will be triggered
          * at the appropriate time for the applet.
          *
+         * @param constraints the type of constraints that were updated
          * @property constraint
          */
-        virtual void constraintsUpdated();
+        virtual void constraintsUpdated(Plasma::Constraints constraints);
 
         /**
          * Returns the current form factor the applet is being displayed in.
diff --git a/containment.cpp b/containment.cpp
index 7f1ba52f8..4ef54a9e0 100644
--- a/containment.cpp
+++ b/containment.cpp
@@ -427,8 +427,10 @@ void Containment::setFormFactor(FormFactor formFactor)
 
     foreach (Applet* applet, d->applets) {
         d->layout->addItem(applet);
-        applet->updateConstraints();
+        applet->updateConstraints(Plasma::FormFactorConstraint);
     }
+
+    updateConstraints(Plasma::FormFactorConstraint);
 }
 
 FormFactor Containment::formFactor() const
@@ -445,8 +447,10 @@ void Containment::setLocation(Location location)
     d->location = location;
 
     foreach (Applet* applet, d->applets) {
-        applet->updateConstraints();
+        applet->updateConstraints(Plasma::LocationConstraint);
     }
+
+    updateConstraints(Plasma::LocationConstraint);
 }
 
 Location Containment::location() const
@@ -493,7 +497,7 @@ Applet* Containment::addApplet(const QString& name, const QVariantList& args, ui
         d->layout->addItem(applet);
     }
 
-    applet->updateConstraints();
+    applet->updateConstraints(Plasma::AllConstraints);
 
     kDebug() << applet->name() << "sizehint:" << applet->sizeHint()
                                << "geometry:" << applet->geometry();
@@ -555,6 +559,7 @@ void Containment::setScreen(int screen)
     }
 
     d->screen = screen;
+    updateConstraints(Plasma::ScreenConstraint);
 }
 
 int Containment::screen() const
diff --git a/plasma.h b/plasma.h
index 1395847e7..435a45352 100644
--- a/plasma.h
+++ b/plasma.h
@@ -30,6 +30,18 @@
 namespace Plasma
 {
 
+/**
+ * The Constriants enumeration lists the various constraints that Plasma
+ * objects have managed for them and which they may wish to react to,
+ * for instance in Applet::constraintsUpdated
+ */
+enum Constraint { FormFactorConstraint = 1 /** The FormFactor for an object */,
+                  LocationConstraint = 2 /** The Location of an object */,
+                  ScreenConstraint = 4 /** Which screen an object is on */,
+                  AllConstraints = FormFactorConstraint | LocationConstraint | ScreenConstraint
+};
+Q_DECLARE_FLAGS(Constraints, Constraint)
+
 /**
  * The FormFactor enumeration describes how a Plasma::Applet should arrange
  * itself. The value is derived from the container managing the Applet
@@ -125,4 +137,6 @@ PLASMA_EXPORT Direction locationToDirection(Location location);
 
 } // Plasma namespace
 
+Q_DECLARE_OPERATORS_FOR_FLAGS(Plasma::Constraints)
+
 #endif // multiple inclusion guard