[GRASS] hide db driver window on Windows

qgis · Oct 22, 2015 · 54e2a51 · 54e2a51
1 parent f5b0dbe
commit 54e2a51
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Showing 4 changed files with 131 additions and 20 deletions.
diff --git a/src/providers/grass/CMakeLists.txt b/src/providers/grass/CMakeLists.txt
@@ -39,6 +39,7 @@ MACRO(ADD_GRASSLIB GRASS_BUILD_VERSION)
 
     SET (GRASS_LIBRARY_SRCS
       ../qgsgrass.cpp
+      ../qgsgrasswin.cpp
       ../qgsgrassdatafile.cpp
       ../qgsgrassfeatureiterator.cpp
       ../qgsgrassimport.cpp

diff --git a/src/providers/grass/qgsgrassvectormaplayer.cpp b/src/providers/grass/qgsgrassvectormaplayer.cpp
@@ -14,11 +14,13 @@
  *                                                                         *
  ***************************************************************************/
 
+
 #include <QFileInfo>
 
 #include "qgslogger.h"
 
 #include "qgsgrass.h"
+#include "qgsgrasswin.h"
 #include "qgsgrassvectormap.h"
 #include "qgsgrassvectormaplayer.h"
 
@@ -111,26 +113,17 @@ void QgsGrassVectorMapLayer::load()
     QFileInfo di( mMap->grassObject().mapsetPath() + "/vector/" + mMap->grassObject().name() + "/dbln" );
     mLastLoaded = di.lastModified();
 
-    QgsGrass::lock();
-    dbDriver *databaseDriver = 0;
-    QString error = QString( "Cannot open database %1 by driver %2" ).arg( mFieldInfo->database, mFieldInfo->driver );
-    G_TRY
-    {
-      setMapset();
-      databaseDriver = db_start_driver_open_database( mFieldInfo->driver, mFieldInfo->database );
-    }
-    G_CATCH( QgsGrass::Exception &e )
-    {
-      QgsGrass::warning( error + " : " + e.what() );
-    }
+    QString error;
+    dbDriver *databaseDriver = openDriver( error );
 
-    if ( !databaseDriver )
+    if ( !databaseDriver || !error.isEmpty() )
     {
       QgsDebugMsg( error );
     }
     else
     {
       QgsDebugMsg( "Database opened -> open select cursor" );
+      QgsGrass::lock(); // not sure if lock is necessary
       dbString dbstr;
       db_init_string( &dbstr );
       db_set_string( &dbstr, ( char * )"select * from " );
@@ -286,8 +279,8 @@ void QgsGrassVectorMapLayer::load()
         QgsDebugMsg( QString( "mTableFields.size = %1" ).arg( mTableFields.size() ) );
         QgsDebugMsg( QString( "number of attributes = %1" ).arg( mAttributes.size() ) );
       }
+      QgsGrass::unlock();
     }
-    QgsGrass::unlock();
   }
 
   // Add cat if no attribute fields exist (otherwise qgis crashes)
@@ -427,6 +420,7 @@ dbDriver * QgsGrassVectorMapLayer::openDriver( QString &error )
 {
   QgsDebugMsg( "entered" );
   dbDriver * driver = 0;
+
   if ( !mFieldInfo )
   {
     error = tr( "No field info" );
@@ -435,17 +429,33 @@ dbDriver * QgsGrassVectorMapLayer::openDriver( QString &error )
   else
   {
     QgsDebugMsg( "Field info found -> open database" );
-    setMapset();
-    driver = db_start_driver_open_database( mFieldInfo->driver, mFieldInfo->database );
-
-    if ( !driver )
+    QString err = QString( "Cannot open database %1 by driver %2" ).arg( mFieldInfo->database, mFieldInfo->driver );
+    QgsGrass::lock();
+    G_TRY
+    {
+      setMapset();
+      driver = db_start_driver_open_database( mFieldInfo->driver, mFieldInfo->database );
+      if ( !driver )
+      {
+        error = err;
+        QgsDebugMsg( error );
+      }
+    }
+    G_CATCH( QgsGrass::Exception &e )
     {
-      error = tr( "Cannot open database %1 by driver %2" ).arg( mFieldInfo->database, mFieldInfo->driver );
+      error = err + " : " + e.what();
       QgsDebugMsg( error );
     }
-    else
+    QgsGrass::unlock();
+
+    if ( driver )
     {
       QgsDebugMsg( "Database opened" );
+#ifdef Q_OS_WIN
+      // Driver on Windows opens black window:
+      // https://lists.osgeo.org/pipermail/grass-dev/2015-October/076831.html
+      QgsGrassWin::hideWindow( driver->pid );
+#endif
     }
   }
   return driver;

diff --git a/src/providers/grass/qgsgrasswin.cpp b/src/providers/grass/qgsgrasswin.cpp
@@ -0,0 +1,73 @@
+/***************************************************************************
+                          qgsgrasswin.cpp
+                             -------------------
+    begin                : October, 2015
+    copyright            : (C) 2015 by Radim Blazek
+    email                : radim.blazek@gmail.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 <QtGlobal>
+
+#include "qgslogger.h"
+#include "qgsgrasswin.h"
+
+#ifdef Q_OS_WIN
+#include "Windows.h"
+#include "WinDef.h"
+#include "Winuser.h"
+#endif
+
+#ifdef Q_OS_WIN
+// Ideas/code from http://stackoverflow.com/questions/20162359/c-best-way-to-get-window-handle-of-the-only-window-from-a-process-by-process
+// Get window for pid
+struct EnumData {
+    DWORD dwProcessId;
+    HWND hWnd;
+};
+BOOL CALLBACK EnumProc( HWND hWnd, LPARAM lParam ) {
+    EnumData& ed = *(EnumData*)lParam;
+    DWORD dwProcessId = 0x0;
+    GetWindowThreadProcessId( hWnd, &dwProcessId );
+    if ( ed.dwProcessId == dwProcessId ) {
+        ed.hWnd = hWnd;
+        SetLastError( ERROR_SUCCESS );
+        return FALSE;
+    }
+    return TRUE;
+}
+HWND FindWindowFromProcessId( DWORD dwProcessId ) {
+    EnumData ed = { dwProcessId };
+    if ( !EnumWindows( EnumProc, (LPARAM)&ed ) &&
+         ( GetLastError() == ERROR_SUCCESS ) ) {
+        return ed.hWnd;
+    }
+    return NULL;
+}
+#endif
+
+void QgsGrassWin::hideWindow( int pid )
+{
+  Q_UNUSED(pid)
+  QgsDebugMsg( QString("pid = %1").arg(pid) );
+#ifdef Q_OS_WIN
+  HWND hWnd = FindWindowFromProcessId( (DWORD)pid );
+  if ( hWnd )
+  {
+    QgsDebugMsg( "driver window found -> minimize" );
+  }
+  else
+  {
+    QgsDebugMsg( "cannot find driver window" );
+  }
+  // Unfortunately the window opens first for a moment
+  ShowWindow( hWnd, SW_HIDE);
+#endif
+}
diff --git a/src/providers/grass/qgsgrasswin.h b/src/providers/grass/qgsgrasswin.h
@@ -0,0 +1,27 @@
+/***************************************************************************
+                          qgsgrasswin.h
+                             -------------------
+    begin                : October, 2015
+    copyright            : (C) 2015 by Radim Blazek
+    email                : radim.blazek@gmail.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 QGSGRASSWIN_H
+#define QGSGRASSWIN_H
+
+// Windows utils
+class GRASS_LIB_EXPORT QgsGrassWin
+{
+  public:
+    static void hideWindow( int pid );
+};
+
+#endif // QGSGRASSWIN_H