Style manager code cleanups

Author: wonder-sk

src/app/qgsmaplayerstyleguiutils.cpp

@@ -1,9 +1,25 @@
+/***************************************************************************
+  qgsmaplayerstyleguiutils.cpp
+  --------------------------------------
+  Date                 : January 2015
+  Copyright            : (C) 2015 by Martin Dobias
+  Email                : wonder dot sk at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
 #include "qgsmaplayerstyleguiutils.h"
 
 #include <QAction>
 #include <QInputDialog>
 #include <QMenu>
 
+#include "qgslogger.h"
 #include "qgsmapcanvas.h"
 #include "qgsmaplayer.h"
 #include "qgsmaplayerstylemanager.h"
@@ -58,17 +74,18 @@ void QgsMapLayerStyleGuiUtils::addStyle()
   bool ok;
   QString text = QInputDialog::getText( 0, tr( "New style" ),
                                         tr( "Style name:" ), QLineEdit::Normal,
-                                        "newstyle", &ok );
+                                        "new style", &ok );
   if ( !ok || text.isEmpty() )
     return;
 
   layer->enableStyleManager(); // make sure it exists
 
   bool res = layer->styleManager()->addStyleFromLayer( text );
-  qDebug( "ADD: %d", res );
 
   if ( res ) // make it active!
     layer->styleManager()->setCurrentStyle( text );
+  else
+    QgsDebugMsg( "Failed to add style: " + text );
 }
 
 void QgsMapLayerStyleGuiUtils::useStyle()
@@ -84,7 +101,8 @@ void QgsMapLayerStyleGuiUtils::useStyle()
     name.clear();
 
   bool res = layer->styleManager()->setCurrentStyle( name );
-  qDebug( "USE: %d", res );
+  if ( !res )
+    QgsDebugMsg( "Failed to set current style: " + name );
 
   layer->triggerRepaint();
 }
@@ -113,7 +131,8 @@ void QgsMapLayerStyleGuiUtils::removeStyle()
   bool needsRefresh = ( layer->styleManager()->currentStyle() == name );
 
   bool res = layer->styleManager()->removeStyle( name );
-  qDebug( "DEL: %d", res );
+  if ( !res )
+    QgsDebugMsg( "Failed to remove style: " + name );
 
   if ( needsRefresh )
     layer->triggerRepaint();

src/app/qgsmaplayerstyleguiutils.h

@@ -1,3 +1,18 @@
+/***************************************************************************
+  qgsmaplayerstyleguiutils.h
+  --------------------------------------
+  Date                 : January 2015
+  Copyright            : (C) 2015 by Martin Dobias
+  Email                : wonder dot sk at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
 #ifndef QGSMAPLAYERSTYLEGUIUTILS_H
 #define QGSMAPLAYERSTYLEGUIUTILS_H
 
@@ -14,6 +29,7 @@ class QgsMapLayerStyleGuiUtils : public QObject, public QgsSingleton<QgsMapLayer
     Q_OBJECT
   public:
 
+    //! Return menu instance with actions for the give map layer
     QMenu* createStyleManagerMenu( QgsMapLayer* layer );
 
   private:

src/core/qgsmaplayerstylemanager.cpp

@@ -1,5 +1,21 @@
+/***************************************************************************
+  qgsmaplayerstylemanager.cpp
+  --------------------------------------
+  Date                 : January 2015
+  Copyright            : (C) 2015 by Martin Dobias
+  Email                : wonder dot sk at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
 #include "qgsmaplayerstylemanager.h"
 
+#include "qgslogger.h"
 #include "qgsmaplayer.h"
 
 #include <QDomElement>
@@ -10,7 +26,7 @@ QgsMapLayerStyleManager::QgsMapLayerStyleManager( QgsMapLayer* layer )
     : mLayer( layer )
 {
   QgsMapLayerStyle defaultStyle;
-  defaultStyle.loadFromLayer( mLayer );
+  defaultStyle.readFromLayer( mLayer );
   mStyles.insert( QString(), defaultStyle );
 }
 
@@ -74,7 +90,7 @@ bool QgsMapLayerStyleManager::addStyle( const QString& name, const QgsMapLayerSt
 bool QgsMapLayerStyleManager::addStyleFromLayer( const QString& name )
 {
   QgsMapLayerStyle style;
-  style.loadFromLayer( mLayer );
+  style.readFromLayer( mLayer );
   return addStyle( name, style );
 }
 
@@ -114,13 +130,13 @@ bool QgsMapLayerStyleManager::setCurrentStyle( const QString& name )
 
   syncCurrentStyle(); // sync before unloading it
   mCurrentStyle = name;
-  mStyles[mCurrentStyle].applyToLayer( mLayer );
+  mStyles[mCurrentStyle].writeToLayer( mLayer );
   return true;
 }
 
 void QgsMapLayerStyleManager::syncCurrentStyle()
 {
-  mStyles[mCurrentStyle].loadFromLayer( mLayer );
+  mStyles[mCurrentStyle].readFromLayer( mLayer );
 }
 
 // -----
@@ -139,22 +155,22 @@ QString QgsMapLayerStyle::dump() const
   return mXmlData;
 }
 
-void QgsMapLayerStyle::loadFromLayer( QgsMapLayer* layer )
+void QgsMapLayerStyle::readFromLayer( QgsMapLayer* layer )
 {
   QString errorMsg;
   QDomDocument doc;
   layer->exportNamedStyle( doc, errorMsg );
   if ( !errorMsg.isEmpty() )
   {
-    qDebug( " ERR: %s", errorMsg.toAscii().data() );
+    QgsDebugMsg( "Failed to export style from layer: " + errorMsg );
     return;
   }
 
   QTextStream stream( &mXmlData );
   doc.save( stream, 0 );
 }
 
-void QgsMapLayerStyle::applyToLayer( QgsMapLayer* layer ) const
+void QgsMapLayerStyle::writeToLayer( QgsMapLayer* layer ) const
 {
   // QgsMapLayer does not have a importNamedStyle() method - working it around like this
   QTemporaryFile f;
@@ -164,9 +180,8 @@ void QgsMapLayerStyle::applyToLayer( QgsMapLayer* layer ) const
 
   bool res;
   QString status = layer->loadNamedStyle( f.fileName(), res );
-  qDebug( "APPLY: %s", status.toAscii().data() );
   if ( !res )
-    qDebug( " APPLY ERR!" );
+    QgsDebugMsg( "Failed to import style to layer: " + status );
 }
 
 void QgsMapLayerStyle::readXml( const QDomElement& styleElement )

src/core/qgsmaplayerstylemanager.h

@@ -1,56 +1,113 @@
+/***************************************************************************
+  qgsmaplayerstylemanager.h
+  --------------------------------------
+  Date                 : January 2015
+  Copyright            : (C) 2015 by Martin Dobias
+  Email                : wonder dot sk at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
 #ifndef QGSMAPLAYERSTYLEMANAGER_H
 #define QGSMAPLAYERSTYLEMANAGER_H
 
 
 class QgsMapLayer;
 
-
 #include <QByteArray>
 #include <QMap>
 #include <QStringList>
 
 class QDomElement;
 
-/** stores style information (renderer, transparency, labeling, diagrams etc.) applicable to a map layer */
-class QgsMapLayerStyle
+/**
+ * Stores style information (renderer, transparency, labeling, diagrams etc.) applicable to a map layer.
+ *
+ * Stored data are considered as opaque - it is not possible to access them directly or modify them - it is
+ * only possible to read or write layer's current style.
+ *
+ * @note added in 2.8
+ */
+class CORE_EXPORT QgsMapLayerStyle
 {
   public:
-    QgsMapLayerStyle(); // consutrct invalid style
+    //! construct invalid style
+    QgsMapLayerStyle();
 
+    //! Tell whether the style is valid (i.e. there is something stored in it)
     bool isValid() const;
 
-    QString dump() const; // for debugging only
+    //! Return information about the style - for debugging purposes only
+    QString dump() const;
 
-    void loadFromLayer( QgsMapLayer* layer );
-    void applyToLayer( QgsMapLayer* layer ) const;
+    //! Store layer's active style information in the instance
+    void readFromLayer( QgsMapLayer* layer );
+    //! Apply stored layer's style information to the layer
+    void writeToLayer( QgsMapLayer* layer ) const;
 
+    //! Read style configuration (for project file reading)
     void readXml( const QDomElement& styleElement );
+    //! Write style configuration (for project file writing)
     void writeXml( QDomElement& styleElement ) const;
 
   private:
     QByteArray mXmlData;
 };
 
 
-/** Management of styles for use with one map layer */
-class QgsMapLayerStyleManager
+/**
+ * Management of styles for use with one map layer. Stored styles are identified by their names. The manager
+ * always keep track of which style of the stored ones is currently active. When the current style is changed,
+ * the new style is applied to the associated layer.
+ *
+ * The class takes care of updating itself when the layer's current style configuration changes.
+ * When some of layer style's properties change (e.g. transparency / colors), the style manager will
+ * record them in the currently active style without any extra effort required.
+ *
+ * When an instance is created, it creates "default" style (with empty name) recorded from the associated map layer
+ * and it is set as the current style.
+ *
+ * The instance must always contain at least one style. If no extra styles are wanted, the style manager should get
+ * disabled in QgsMapLayer instance.
+ *
+ * @note added in 2.8
+ */
+class CORE_EXPORT QgsMapLayerStyleManager
 {
   public:
+    //! Construct a style manager associated with a map layer (must not be null)
     QgsMapLayerStyleManager( QgsMapLayer* layer );
 
+    //! Read configuration (for project loading)
     void readXml( const QDomElement& mgrElement );
+    //! Write configuration (for project saving)
     void writeXml( QDomElement& mgrElement ) const;
 
+    //! Return list of all defined style names
     QStringList styles() const;
+    //! Return data of a stored style - accessed by its unique name
     QgsMapLayerStyle style( const QString& name ) const;
 
+    //! Add a style with given name and data
+    //! @return true on success (name is unique and style is valid)
     bool addStyle( const QString& name, const QgsMapLayerStyle& style );
     //! Add style by cloning the current one
+    //! @return true on success
     bool addStyleFromLayer( const QString& name );
+    //! Remove a stored style
+    //! @return true on success (style exists and it is not the last one)
     bool removeStyle( const QString& name );
 
+    //! Return name of the current style
     QString currentStyle() const;
-    bool setCurrentStyle( const QString& name ); // applies to the mLayer! (+ sync previous style)
+    //! Set a different style as the current style - will apply it to the layer
+    //! @return true on success
+    bool setCurrentStyle( const QString& name );
 
   private:
     void syncCurrentStyle();

tests/src/core/testqgsmaplayerstylemanager.cpp

@@ -86,25 +86,25 @@ void TestQgsMapLayerStyleManager::testStyle()
   mVL->setRendererV2( new QgsSingleSymbolRendererV2( sym1 ) );
 
   QgsMapLayerStyle st1;
-  st1.loadFromLayer( mVL );
+  st1.readFromLayer( mVL );
   QCOMPARE( st1.isValid(), true );
 
   qDebug( "CNT-1: %s", st1.dump().toAscii().data() );
 
   mVL->setRendererV2( new QgsSingleSymbolRendererV2( sym2 ) );
 
   QgsMapLayerStyle st2;
-  st2.loadFromLayer( mVL );
+  st2.readFromLayer( mVL );
 
   qDebug( "CNT-2: %s", st2.dump().toAscii().data() );
 
-  st1.applyToLayer( mVL );
+  st1.writeToLayer( mVL );
 
   QgsSingleSymbolRendererV2* r1 = dynamic_cast<QgsSingleSymbolRendererV2*>( mVL->rendererV2() );
   QVERIFY( r1 );
   QCOMPARE( r1->symbol()->color(), QColor( Qt::magenta ) );
 
-  st2.applyToLayer( mVL );
+  st2.writeToLayer( mVL );
 
   QgsSingleSymbolRendererV2* r2 = dynamic_cast<QgsSingleSymbolRendererV2*>( mVL->rendererV2() );
   QVERIFY( r2 );