Fix #7195, transparency options in composer should be 0-100%

Author: dakcarto

src/app/composer/qgscomposeritemwidget.cpp

@@ -97,7 +97,7 @@ void QgsComposerItemWidget::on_mBackgroundColorButton_clicked()
   }
 
   mItem->beginCommand( tr( "Background color changed" ) );
-  newBackgroundColor.setAlpha( mTransparencySlider->value() );
+  newBackgroundColor.setAlpha( 255 - ( mTransparencySpinBox->value() * 2.55 ) );
   mItem->setBrush( QBrush( QColor( newBackgroundColor ), Qt::SolidPattern ) );
   //if the item is a composer map, we need to regenerate the map image
   //because it usually is cached
@@ -123,25 +123,22 @@ void QgsComposerItemWidget::on_mTransparencySpinBox_valueChanged( int value )
   changeItemTransparency( value );
 }
 
-void QgsComposerItemWidget::on_mTransparencySlider_sliderReleased()
+void QgsComposerItemWidget::on_mTransparencySlider_valueChanged( int value )
 {
   if ( !mItem )
   {
     return;
   }
-  int value = mTransparencySlider->value();
-  mTransparencySpinBox->blockSignals( true );
+  // do item updates only off of mTransparencySpinBox valueChanged
   mTransparencySpinBox->setValue( value );
-  mTransparencySpinBox->blockSignals( false );
-  changeItemTransparency( value );
 }
 
 void QgsComposerItemWidget::changeItemTransparency( int value )
 {
-  mItem->beginCommand( tr( "Item Transparency changed" ) );
+  mItem->beginCommand( tr( "Item transparency changed" ) );
   QBrush itemBrush = mItem->brush();
   QColor brushColor = itemBrush.color();
-  brushColor.setAlpha( 255 - value );
+  brushColor.setAlpha( 255 - ( value * 2.55 ) );
   mItem->setBrush( QBrush( brushColor ) );
   mItem->update();
   mItem->endCommand();
@@ -354,8 +351,9 @@ void QgsComposerItemWidget::setValuesForGuiElements()
   mItemIdLineEdit->blockSignals( true );
   mTransparencySpinBox->blockSignals( true );
 
-  mTransparencySpinBox->setValue( 255 - mItem->brush().color().alpha() );
-  mTransparencySlider->setValue( 255 - mItem->brush().color().alpha() );
+  int alphaPercent = ( 255 - mItem->brush().color().alpha() ) / 2.55;
+  mTransparencySpinBox->setValue( alphaPercent );
+  mTransparencySlider->setValue( alphaPercent );
   mOutlineWidthSpinBox->setValue( mItem->pen().widthF() );
   mItemIdLineEdit->setText( mItem->id() );
   mFrameGroupBox->setChecked( mItem->hasFrame() );

src/app/composer/qgscomposeritemwidget.h

@@ -39,7 +39,7 @@ class QgsComposerItemWidget: public QWidget, private Ui::QgsComposerItemWidgetBa
   public slots:
     void on_mFrameColorButton_clicked();
     void on_mBackgroundColorButton_clicked();
-    void on_mTransparencySlider_sliderReleased();
+    void on_mTransparencySlider_valueChanged( int value );
     void on_mTransparencySpinBox_valueChanged( int value );
     void on_mOutlineWidthSpinBox_valueChanged( double d );
     void on_mFrameGroupBox_toggled( bool state );

src/ui/qgscomposeritemwidgetbase.ui

@@ -318,7 +318,7 @@
         <item>
          <widget class="QSlider" name="mTransparencySlider">
           <property name="maximum">
-           <number>255</number>
+           <number>100</number>
           </property>
           <property name="orientation">
            <enum>Qt::Horizontal</enum>
@@ -327,8 +327,11 @@
         </item>
         <item>
          <widget class="QSpinBox" name="mTransparencySpinBox">
+          <property name="suffix">
+           <string>%</string>
+          </property>
           <property name="maximum">
-           <number>255</number>
+           <number>100</number>
           </property>
          </widget>
         </item>
@@ -395,38 +398,5 @@
   </customwidget>
  </customwidgets>
  <resources/>
- <connections>
-  <connection>
-   <sender>mTransparencySlider</sender>
-   <signal>valueChanged(int)</signal>
-   <receiver>mTransparencySpinBox</receiver>
-   <slot>setValue(int)</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>255</x>
-     <y>387</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>364</x>
-     <y>389</y>
-    </hint>
-   </hints>
-  </connection>
-  <connection>
-   <sender>mTransparencySpinBox</sender>
-   <signal>valueChanged(int)</signal>
-   <receiver>mTransparencySlider</receiver>
-   <slot>setValue(int)</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>364</x>
-     <y>389</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>271</x>
-     <y>387</y>
-    </hint>
-   </hints>
-  </connection>
- </connections>
+ <connections/>
 </ui>