Added setting of scale programatially

src/gui/qgsscalecombobox.cpp

@@ -106,6 +106,26 @@ QString QgsScaleComboBox::scaleString()
 {
   return toString( mScale );
 }
+
+//! Function to set the selected scale from text
+// @note added in 2.0
+bool QgsScaleComboBox::setScaleString( QString scaleTxt )
+{
+  bool ok;
+  double newScale = toDouble( scaleTxt, &ok );
+  if ( ! ok )
+  {
+    return false;
+  }
+  else
+  {
+    mScale = newScale;
+    setEditText( toString( mScale ) );
+    clearFocus();
+    return true;
+  }
+}
+
 //! Function to read the selected scale as double
 // @note added in 2.0
 double QgsScaleComboBox::scale()
@@ -113,6 +133,13 @@ double QgsScaleComboBox::scale()
   return mScale;
 }
 
+//! Function to set the selected scale from double
+// @note added in 2.0
+void QgsScaleComboBox::setScale( double scale )
+{
+  setScaleString( toString( scale ) );
+}
+
 //! Slot called when QComboBox has changed
 void QgsScaleComboBox::fixupScale()
 {
@@ -128,7 +155,7 @@ void QgsScaleComboBox::fixupScale()
   }
   // We set to the new string representation
   // or reset to the old
-  setEditText( toString( mScale ) );
+  setScale( mScale );
 
   if ( oldScale != mScale )
   {

src/gui/qgsscalecombobox.h

@@ -33,9 +33,16 @@ class GUI_EXPORT QgsScaleComboBox : public QComboBox
     //! Function to read the selected scale as text
     // @note added in 2.0
     QString scaleString();
+    //! Function to set the selected scale from text
+    // @note added in 2.0
+    bool setScaleString( QString scaleTxt );
     //! Function to read the selected scale as double
     // @note added in 2.0
     double scale();
+    //! Function to set the selected scale from double
+    // @note added in 2.0
+    void setScale( double scale );
+
     //! Helper function to convert a double to scale string
     // Performs rounding, so an exact representation is not to
     // be expected.
@@ -45,9 +52,9 @@ class GUI_EXPORT QgsScaleComboBox : public QComboBox
     // @note added in 2.0
     static double toDouble( QString scaleString, bool *ok = NULL );
 
-    //! Signals is emited when user has finished editing/selecting a new scale.
-    // @note added in 2.0
   signals:
+    //! Signal is emitted when *user* has finished editing/selecting a new scale.
+    // @note added in 2.0
     void scaleChanged();
 
   public slots:

tests/src/gui/testqgsscalecombobox.cpp

@@ -94,6 +94,21 @@ void TestQgsScaleComboBox::basic()
   QCOMPARE( s->scaleString(), QString( "1:4" ) );
   QCOMPARE( s->scale(), ( double ) 0.25 );
 
+  // Test setting programatically
+  s->setScale(( double ) 0.19 );
+  QCOMPARE( s->scaleString(), QString( "1:5" ) );
+  QCOMPARE( s->scale(), ( double ) 0.2 );
+
+  // Test setting programatically
+  s->setScaleString( QString( "1:240" ) );
+  QCOMPARE( s->scaleString(), QString( "1:240" ) );
+  QCOMPARE( s->scale(), ( double ) 1.0 / ( double ) 240.0 );
+
+  // Test setting programatically illegal string
+  s->setScaleString( QString( "1:2.4" ) );
+  QCOMPARE( s->scaleString(), QString( "1:240" ) );
+  QCOMPARE( s->scale(), ( double ) 1.0 / ( double ) 240.0 );
+
 };
 
 void TestQgsScaleComboBox::slot_test()