[diagrams] Diagram fixes and UI improvements (Fix #7960)

* Use correct color for pie chart if only one value is >0 * Show default text in scaling text box
qgis · Jun 7, 2013 · 8c840e9 · 8c840e9
1 parent eda9cd3
commit 8c840e9
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Showing 2 changed files with 17 additions and 11 deletions.
diff --git a/src/core/diagram/qgspiediagram.cpp b/src/core/diagram/qgspiediagram.cpp
@@ -128,19 +128,22 @@ void QgsPieDiagram::renderDiagram( const QgsAttributes& att, QgsRenderContext& c
     QList< QColor >::const_iterator colIt = s.categoryColors.constBegin();
     for ( ; valIt != values.constEnd(); ++valIt, ++colIt )
     {
-      currentAngle = *valIt / valSum * 360 * 16;
-      mCategoryBrush.setColor( *colIt );
-      p->setBrush( mCategoryBrush );
-      // if only 1 value is > 0, draw a circle
-      if ( valCount == 1 )
+      if ( *valIt )
       {
-        p->drawEllipse( baseX, baseY, w, h );
+        currentAngle = *valIt / valSum * 360 * 16;
+        mCategoryBrush.setColor( *colIt );
+        p->setBrush( mCategoryBrush );
+        // if only 1 value is > 0, draw a circle
+        if ( valCount == 1 )
+        {
+          p->drawEllipse( baseX, baseY, w, h );
+        }
+        else
+        {
+          p->drawPie( baseX, baseY, w, h, totalAngle + s.angleOffset, currentAngle );
+        }
+        totalAngle += currentAngle;
       }
-      else
-      {
-        p->drawPie( baseX, baseY, w, h, totalAngle + s.angleOffset, currentAngle );
-      }
-      totalAngle += currentAngle;
     }
   }
   else // valSum > 0

diff --git a/src/ui/qgsdiagrampropertiesbase.ui b/src/ui/qgsdiagrampropertiesbase.ui
@@ -431,6 +431,9 @@
                          <string>The attribute value you enter here will correspond to the size entered in the field &quot;Size&quot; and the chosen &quot;Size unit&quot;.
 Leave empty to automatically apply the maximum value.</string>
                         </property>
+                        <property name="placeholderText">
+                         <string>Empty: Use maximum value</string>
+                        </property>
                        </widget>
                       </item>
                      </layout>