GuiBibtex: add button to edit individual databases externally

This complements the inset context menu function, which only allows for
editing all databases externally

src/frontends/qt4/GuiBibtex.cpp

@@ -185,6 +185,7 @@ void GuiBibtex::setButtons()
 void GuiBibtex::selUpdated()
 {
 	selectionManager->update();
+	editPB->setEnabled(deletePB->isEnabled());
 	changed();
 }
 
@@ -240,6 +241,19 @@ void GuiBibtex::browseBibPressed()
 }
 
 
+void GuiBibtex::on_editPB_clicked()
+{
+	QModelIndexList selIdx =
+		selectedLV->selectionModel()->selectedIndexes();
+	if (selIdx.isEmpty())
+		return;
+	QModelIndex idx = selIdx.first();
+	QString sel = idx.data().toString();
+	FuncRequest fr(LFUN_INSET_EDIT, fromqstr(sel));
+	dispatch(fr);
+}
+
+
 void GuiBibtex::rescanClicked()
 {
 	rescanBibStyles();
@@ -297,6 +311,7 @@ void GuiBibtex::setSelectedBibs(QStringList const sl)
 				   "encoding than specified below, set it here"));
 		selectedLV->setIndexWidget(selected_model_.index(i, 1), cb);
 	}
+	editPB->setEnabled(deletePB->isEnabled());
 }
 
 
@@ -392,6 +407,7 @@ void GuiBibtex::updateContents()
 		biblatexOptsLE->setText(toqstr(params_["biblatexopts"]));
 
 	setFileEncodings(getVectorFromString(params_["file_encodings"], from_ascii("\t")));
+	editPB->setEnabled(deletePB->isEnabled());
 }
 
 
@@ -399,8 +415,8 @@ void GuiBibtex::applyView()
 {
 	docstring dbs;
 
-	unsigned int maxCount = selected_bibs_.count();
+	int maxCount = selected_bibs_.count();
-	for (unsigned int i = 0; i < maxCount; i++) {
+	for (int i = 0; i < maxCount; i++) {
 		if (i != 0)
 			dbs += ',';
 		QString item = selected_bibs_.at(i);

src/frontends/qt4/GuiBibtex.h

@@ -39,6 +39,7 @@ private Q_SLOTS:
 	void on_buttonBox_accepted();
 	void browseBstPressed();
 	void browseBibPressed();
+	void on_editPB_clicked();
 	void databaseChanged();
 	void rescanClicked();
 	void selUpdated();

src/frontends/qt4/ui/BibtexUi.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>523</width>
-    <height>576</height>
+    <height>617</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -141,6 +141,33 @@
           </property>
          </widget>
         </item>
+        <item>
+         <spacer name="verticalSpacer_2">
+          <property name="orientation">
+           <enum>Qt::Vertical</enum>
+          </property>
+          <property name="sizeHint" stdset="0">
+           <size>
+            <width>20</width>
+            <height>40</height>
+           </size>
+          </property>
+         </spacer>
+        </item>
+        <item>
+         <widget class="QPushButton" name="editPB">
+          <property name="toolTip">
+           <string>Edit selected database externally</string>
+          </property>
+          <property name="text">
+           <string>&amp;Edit...</string>
+          </property>
+          <property name="icon">
+           <iconset>
+            <normaloff>.</normaloff>.</iconset>
+          </property>
+         </widget>
+        </item>
         <item>
          <spacer name="verticalSpacer">
           <property name="orientation">

src/insets/InsetBibtex.cpp

@@ -85,7 +85,7 @@ void InsetBibtex::doDispatch(Cursor & cur, FuncRequest & cmd)
 	switch (cmd.action()) {
 
 	case LFUN_INSET_EDIT:
-		editDatabases();
+		editDatabases(cmd.argument());
 		break;
 
 	case LFUN_INSET_MODIFY: {
@@ -132,7 +132,7 @@ bool InsetBibtex::getStatus(Cursor & cur, FuncRequest const & cmd,
 }
 
 
-void InsetBibtex::editDatabases() const
+void InsetBibtex::editDatabases(docstring const db) const
 {
 	vector<docstring> bibfilelist = getVectorFromString(getParam("bibfiles"));
 
@@ -140,7 +140,7 @@ void InsetBibtex::editDatabases() const
 		return;
 
 	size_t nr_databases = bibfilelist.size();
-	if (nr_databases > 1) {
+	if (nr_databases > 1 && db.empty()) {
 			docstring const engine = usingBiblatex() ? _("Biblatex") : _("BibTeX");
 			docstring message = bformat(_("The %1$s[[BibTeX/Biblatex]] inset includes %2$s databases.\n"
 						       "If you proceed, all of them will be opened."),
@@ -155,6 +155,8 @@ void InsetBibtex::editDatabases() const
 	vector<docstring>::const_iterator it = bibfilelist.begin();
 	vector<docstring>::const_iterator en = bibfilelist.end();
 	for (; it != en; ++it) {
+		if (!db.empty() && db != *it)
+			continue;
 		FileName const bibfile = buffer().getBibfilePath(*it);
 		theFormats().edit(buffer(), bibfile,
 		     theFormats().getFormatFromFile(bibfile));

src/insets/InsetBibtex.h

@@ -82,7 +82,7 @@ public:
 
 private:
 	///
-	void editDatabases() const;
+	void editDatabases(docstring const db = docstring()) const;
 	///
 	void parseBibTeXFiles(support::FileNameList &) const;
 	///