Add custom drop handlers for layout windows

python/gui/gui_auto.sip

@@ -290,6 +290,7 @@
 %Include layertree/qgslayertreemapcanvasbridge.sip
 %Include layertree/qgslayertreeview.sip
 %Include layertree/qgslayertreeviewdefaultactions.sip
+%Include layout/qgslayoutcustomdrophandler.sip
 %Include layout/qgslayoutdesignerinterface.sip
 %Include layout/qgslayoutitemcombobox.sip
 %Include layout/qgslayoutitemguiregistry.sip

python/gui/layout/qgslayoutcustomdrophandler.sip

@@ -0,0 +1,42 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/layout/qgslayoutcustomdrophandler.h                          *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+class QgsLayoutCustomDropHandler : QObject
+{
+%Docstring
+ Abstract base class that may be implemented to handle new types of data to be dropped in QGIS layouts.
+
+.. versionadded:: 3.0
+%End
+
+%TypeHeaderCode
+#include "qgslayoutcustomdrophandler.h"
+%End
+  public:
+    virtual ~QgsLayoutCustomDropHandler();
+
+    virtual bool handleFileDrop( const QString &file );
+%Docstring
+ Called when the specified ``file`` has been dropped onto a QGIS layout. If true
+ is returned, then the handler has accepted this file and it should not
+ be further processed (e.g. by other QgsLayoutCustomDropHandler).
+
+ The base class implementation does nothing.
+ :rtype: bool
+%End
+};
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/layout/qgslayoutcustomdrophandler.h                          *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/

python/gui/qgisinterface.sip

@@ -1116,6 +1116,24 @@ Unregister a previously registered action. (e.g. when plugin is going to be unlo
 .. seealso:: :py:func:`registerCustomDropHandler()`
 %End
 
+    virtual void registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) = 0;
+%Docstring
+ Register a new custom drop ``handler`` for layout windows.
+.. versionadded:: 3.0
+.. note::
+
+   Ownership of the factory is not transferred, and the factory must
+       be unregistered when plugin is unloaded.
+.. seealso:: unregisterCustomLayoutDropHandler() *
+%End
+
+    virtual void unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) = 0;
+%Docstring
+ Unregister a previously registered custom drop ``handler`` for layout windows.
+.. versionadded:: 3.0
+.. seealso:: registerCustomLayoutDropHandler() *
+%End
+
 
     virtual void openURL( const QString &url, bool useQgisDocDirectory = true ) = 0 /Deprecated/;
 %Docstring

src/app/layout/qgslayoutdesignerdialog.cpp

@@ -22,6 +22,7 @@
 #include "qgslogger.h"
 #include "qgslayout.h"
 #include "qgslayoutappmenuprovider.h"
+#include "qgslayoutcustomdrophandler.h"
 #include "qgslayoutview.h"
 #include "qgslayoutviewtooladditem.h"
 #include "qgslayoutviewtooladdnodeitem.h"
@@ -900,6 +901,96 @@ void QgsLayoutDesignerDialog::closeEvent( QCloseEvent * )
   saveWindowState();
 }
 
+void QgsLayoutDesignerDialog::dropEvent( QDropEvent *event )
+{
+  // dragging app is locked for the duration of dropEvent. This causes explorer windows to hang
+  // while large projects/layers are loaded. So instead we return from dropEvent as quickly as possible
+  // and do the actual handling of the drop after a very short timeout
+  QTimer *timer = new QTimer( this );
+  timer->setSingleShot( true );
+  timer->setInterval( 50 );
+
+  // get the file list
+  QList<QUrl>::iterator i;
+  QList<QUrl>urls = event->mimeData()->urls();
+  QStringList files;
+  for ( i = urls.begin(); i != urls.end(); ++i )
+  {
+    QString fileName = i->toLocalFile();
+#ifdef Q_OS_MAC
+    // Mac OS X 10.10, under Qt4.8 ,changes dropped URL format
+    // https://bugreports.qt.io/browse/QTBUG-40449
+    // [pzion 20150805] Work around
+    if ( fileName.startsWith( "/.file/id=" ) )
+    {
+      QgsDebugMsg( "Mac dropped URL with /.file/id= (converting)" );
+      CFStringRef relCFStringRef =
+        CFStringCreateWithCString(
+          kCFAllocatorDefault,
+          fileName.toUtf8().constData(),
+          kCFStringEncodingUTF8
+        );
+      CFURLRef relCFURL =
+        CFURLCreateWithFileSystemPath(
+          kCFAllocatorDefault,
+          relCFStringRef,
+          kCFURLPOSIXPathStyle,
+          false // isDirectory
+        );
+      CFErrorRef error = 0;
+      CFURLRef absCFURL =
+        CFURLCreateFilePathURL(
+          kCFAllocatorDefault,
+          relCFURL,
+          &error
+        );
+      if ( !error )
+      {
+        static const CFIndex maxAbsPathCStrBufLen = 4096;
+        char absPathCStr[maxAbsPathCStrBufLen];
+        if ( CFURLGetFileSystemRepresentation(
+               absCFURL,
+               true, // resolveAgainstBase
+               reinterpret_cast<UInt8 *>( &absPathCStr[0] ),
+               maxAbsPathCStrBufLen ) )
+        {
+          fileName = QString( absPathCStr );
+        }
+      }
+      CFRelease( absCFURL );
+      CFRelease( relCFURL );
+      CFRelease( relCFStringRef );
+    }
+#endif
+    // seems that some drag and drop operations include an empty url
+    // so we test for length to make sure we have something
+    if ( !fileName.isEmpty() )
+    {
+      files << fileName;
+    }
+  }
+
+  connect( timer, &QTimer::timeout, this, [this, timer, files]
+  {
+    for ( const QString &file : qgis::as_const( files ) )
+    {
+      const QVector<QPointer<QgsLayoutCustomDropHandler >> handlers = QgisApp::instance()->customLayoutDropHandlers();
+      for ( QgsLayoutCustomDropHandler *handler : handlers )
+      {
+        if ( handler && handler->handleFileDrop( file ) )
+        {
+          break;
+        }
+      }
+    }
+
+    timer->deleteLater();
+  } );
+
+  event->acceptProposedAction();
+  timer->start();
+}
+
 void QgsLayoutDesignerDialog::itemTypeAdded( int id )
 {
   if ( QgsGui::layoutItemGuiRegistry()->itemMetadata( id )->flags() & QgsLayoutItemAbstractGuiMetadata::FlagNoCreationTools )

src/app/layout/qgslayoutdesignerdialog.h

@@ -238,6 +238,7 @@ class QgsLayoutDesignerDialog: public QMainWindow, private Ui::QgsLayoutDesigner
   protected:
 
     virtual void closeEvent( QCloseEvent * ) override;
+    virtual void dropEvent( QDropEvent *event ) override;
 
   private slots:
 

src/app/qgisapp.cpp

@@ -205,6 +205,7 @@ Q_GUI_EXPORT extern int qt_defaultDpiX();
 #include "qgslayertreeutils.h"
 #include "qgslayertreeview.h"
 #include "qgslayertreeviewdefaultactions.h"
+#include "qgslayoutcustomdrophandler.h"
 #include "qgslayoutdesignerdialog.h"
 #include "qgslayoutmanager.h"
 #include "qgslayoutapputils.h"
@@ -1400,6 +1401,7 @@ QgisApp::~QgisApp()
   delete mTray;
   delete mDataSourceManagerDialog;
   qDeleteAll( mCustomDropHandlers );
+  qDeleteAll( mCustomLayoutDropHandlers );
 
   // This function *MUST* be the last one called, as it destroys in
   // particular GDAL. As above objects can hold GDAL/OGR objects, it is not
@@ -1560,6 +1562,22 @@ void QgisApp::unregisterCustomDropHandler( QgsCustomDropHandler *handler )
   mCustomDropHandlers.removeOne( handler );
 }
 
+void QgisApp::registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler )
+{
+  if ( !mCustomLayoutDropHandlers.contains( handler ) )
+    mCustomLayoutDropHandlers << handler;
+}
+
+void QgisApp::unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler )
+{
+  mCustomLayoutDropHandlers.removeOne( handler );
+}
+
+QVector<QPointer<QgsLayoutCustomDropHandler> > QgisApp::customLayoutDropHandlers() const
+{
+  return mCustomLayoutDropHandlers;
+}
+
 void QgisApp::handleDropUriList( const QgsMimeDataUtils::UriList &lst )
 {
   // insert items in reverse order as each one is inserted on top of previous one

src/app/qgisapp.h

@@ -62,6 +62,7 @@ class QgsGeometry;
 class QgsLayerTreeMapCanvasBridge;
 class QgsLayerTreeView;
 class QgsLayout;
+class QgsLayoutCustomDropHandler;
 class QgsLayoutDesignerDialog;
 class QgsLayoutDesignerInterface;
 class QgsMapCanvas;
@@ -644,6 +645,15 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     //! Unregister a previously registered custom drop handler.
     void unregisterCustomDropHandler( QgsCustomDropHandler *handler );
 
+    //! Register a new custom layout drop handler.
+    void registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler );
+
+    //! Unregister a previously registered custom layout drop handler.
+    void unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler );
+
+    //! Returns a list of registered custom layout drop handlers.
+    QVector<QPointer<QgsLayoutCustomDropHandler >> customLayoutDropHandlers() const;
+
     //! Returns the active map layer.
     QgsMapLayer *activeLayer();
 
@@ -2119,6 +2129,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     QList<QPointer<QgsOptionsWidgetFactory>> mOptionsWidgetFactories;
 
     QVector<QPointer<QgsCustomDropHandler>> mCustomDropHandlers;
+    QVector<QPointer<QgsLayoutCustomDropHandler>> mCustomLayoutDropHandlers;
 
     QDateTime mProjectLastModified;
 

src/app/qgisappinterface.cpp

@@ -584,6 +584,16 @@ void QgisAppInterface::registerCustomDropHandler( QgsCustomDropHandler *handler
   qgis->registerCustomDropHandler( handler );
 }
 
+void QgisAppInterface::registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler )
+{
+  qgis->registerCustomLayoutDropHandler( handler );
+}
+
+void QgisAppInterface::unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler )
+{
+  qgis->unregisterCustomLayoutDropHandler( handler );
+}
+
 void QgisAppInterface::unregisterCustomDropHandler( QgsCustomDropHandler *handler )
 {
   qgis->unregisterCustomDropHandler( handler );

src/app/qgisappinterface.h

@@ -24,7 +24,6 @@
 
 class QgisApp;
 
-
 /**
  * \class QgisAppInterface
  * \brief Interface class to provide access to private methods in QgisApp
@@ -330,7 +329,7 @@ class APP_EXPORT QgisAppInterface : public QgisInterface
     virtual void unregisterOptionsWidgetFactory( QgsOptionsWidgetFactory *factory ) override;
 
     /**
-     * Register a new custom drop handler.
+     * Register a new custom drop \a handler.
      * \since QGIS 3.0
      * \note Ownership of the factory is not transferred, and the factory must
      *       be unregistered when plugin is unloaded.
@@ -338,11 +337,14 @@ class APP_EXPORT QgisAppInterface : public QgisInterface
     virtual void registerCustomDropHandler( QgsCustomDropHandler *handler ) override;
 
     /**
-     * Unregister a previously registered custom drop handler.
+     * Unregister a previously registered custom drop \a handler.
      * \since QGIS 3.0
      * \see registerCustomDropHandler() */
     virtual void unregisterCustomDropHandler( QgsCustomDropHandler *handler ) override;
 
+    void registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) override;
+    void unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) override;
+
     /**
      * Accessors for inserting items into menus and toolbars.
      * An item can be inserted before any existing action.

src/gui/CMakeLists.txt

@@ -160,6 +160,7 @@ SET(QGIS_GUI_SRCS
   layertree/qgslayertreeview.cpp
   layertree/qgslayertreeviewdefaultactions.cpp
 
+  layout/qgslayoutcustomdrophandler.cpp
   layout/qgslayoutitemguiregistry.cpp
   layout/qgslayoutitemcombobox.cpp
   layout/qgslayoutitemwidget.cpp
@@ -678,6 +679,7 @@ SET(QGIS_GUI_MOC_HDRS
   layertree/qgslayertreeview.h
   layertree/qgslayertreeviewdefaultactions.h
 
+  layout/qgslayoutcustomdrophandler.h
   layout/qgslayoutdesignerinterface.h
   layout/qgslayoutitemcombobox.h
   layout/qgslayoutitemguiregistry.h

src/gui/layout/qgslayoutcustomdrophandler.cpp

@@ -0,0 +1,22 @@
+/***************************************************************************
+    qgslayoutcustomdrophandler.cpp
+    ------------------------------
+    begin                : December 2017
+    copyright            : (C) 2017 by nyall Dawson
+    email                : nyall dot dawson 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 "qgslayoutcustomdrophandler.h"
+
+bool QgsLayoutCustomDropHandler::handleFileDrop( const QString &file )
+{
+  Q_UNUSED( file );
+  return false;
+}

src/gui/layout/qgslayoutcustomdrophandler.h

@@ -0,0 +1,45 @@
+/***************************************************************************
+    qgslayoutcustomdrophandler.h
+    ---------------------
+    begin                : December 2017
+    copyright            : (C) 2017 by nyall Dawson
+    email                : nyall dot dawson 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 QGSLAYOUTCUSTOMDROPHANDLER_H
+#define QGSLAYOUTCUSTOMDROPHANDLER_H
+
+#include "qgis_gui.h"
+#include <QObject>
+
+/**
+ * \ingroup gui
+ * Abstract base class that may be implemented to handle new types of data to be dropped in QGIS layouts.
+ *
+ * \since QGIS 3.0
+ */
+class GUI_EXPORT QgsLayoutCustomDropHandler : public QObject
+{
+    Q_OBJECT
+
+  public:
+    virtual ~QgsLayoutCustomDropHandler() = default;
+
+    /**
+     * Called when the specified \a file has been dropped onto a QGIS layout. If true
+     * is returned, then the handler has accepted this file and it should not
+     * be further processed (e.g. by other QgsLayoutCustomDropHandler).
+     *
+     * The base class implementation does nothing.
+     */
+    virtual bool handleFileDrop( const QString &file );
+};
+
+#endif // QGSLAYOUTCUSTOMDROPHANDLER_H

src/gui/qgisinterface.h

@@ -29,6 +29,7 @@ class QgsAdvancedDigitizingDockWidget;
 class QgsAttributeDialog;
 class QgsComposerInterface;
 class QgsCustomDropHandler;
+class QgsLayoutCustomDropHandler;
 class QgsFeature;
 class QgsLayerTreeMapCanvasBridge;
 class QgsLayerTreeView;
@@ -679,6 +680,20 @@ class GUI_EXPORT QgisInterface : public QObject
      * \see registerCustomDropHandler() */
     virtual void unregisterCustomDropHandler( QgsCustomDropHandler *handler ) = 0;
 
+    /**
+     * Register a new custom drop \a handler for layout windows.
+     * \since QGIS 3.0
+     * \note Ownership of the factory is not transferred, and the factory must
+     *       be unregistered when plugin is unloaded.
+     * \see unregisterCustomLayoutDropHandler() */
+    virtual void registerCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) = 0;
+
+    /**
+     * Unregister a previously registered custom drop \a handler for layout windows.
+     * \since QGIS 3.0
+     * \see registerCustomLayoutDropHandler() */
+    virtual void unregisterCustomLayoutDropHandler( QgsLayoutCustomDropHandler *handler ) = 0;
+
     // @todo is this deprecated in favour of QgsContextHelp?
 
     /**