fix: fix crash when we create a new rc file (language is empty => assert)

docs/API/knut/rcdocument.md

@@ -32,6 +32,7 @@ import Knut
 |[ToolBar](../knut/toolbar.md) |**[action](#action)**(string id)|
 |array<[Action](../knut/action.md)> |**[actionsFromMenu](#actionsFromMenu)**(string menuId)|
 |array<[Action](../knut/action.md)> |**[actionsFromToolbar](#actionsFromToolbar)**(string toolBarId)|
+|string |**[captionDialogForLanguage](#captionDialogForLanguage)**(string language, string dialogId)|
 |void |**[convertActions](#convertActions)**(int flags)|
 ||**[convertAssets](#convertAssets)**(int flags)|
 |string |**[convertLanguageToCode](#convertLanguageToCode)**(string language)|
@@ -126,6 +127,10 @@ Returns all actions used in the menu `menuId`.
 
 Returns all actions used in the toolbar `toolBarId`.
 
+#### <a name="captionDialogForLanguage"></a>string **captionDialogForLanguage**(string language, string dialogId)
+
+Returns the string with `id` for the given `language`.
+
 #### <a name="convertActions"></a>void **convertActions**(int flags)
 
 

src/core/rcdocument.cpp

@@ -486,6 +486,24 @@ QString RcDocument::stringForDialogAndLanguage(const QString &language, const QS
     }
 }
 
+/*!
+ * \qmlmethod string RcDocument::captionDialogForLanguage(string language, string dialogId)
+ * Returns the string with `id` for the given `language`.
+ */
+QString RcDocument::captionDialogForLanguage(const QString &language, const QString &dialogId) const
+{
+    LOG(language, dialogId);
+
+    if (m_rcFile.isValid && m_rcFile.data.contains(language)) {
+        const RcCore::Data data = const_cast<RcCore::RcFile *>(&m_rcFile)->data[language];
+        const auto dialog = data.dialog(dialogId);
+        return dialog->caption;
+    } else {
+        spdlog::warn("{}: language {} does not exist in the rc file.", FUNCTION_NAME, language);
+        return {};
+    }
+}
+
 /*!
  * \qmlmethod string RcDocument::stringForDialog(string dialogId, string id)
  * Returns the string with `id` for the given `dialogid`.

src/core/rcdocument.h

@@ -104,6 +104,8 @@ class RcDocument : public Document
 
     const RcCore::RcFile &file() const;
 
+    Q_INVOKABLE QString captionDialogForLanguage(const QString &language, const QString &dialogId) const;
+
 public slots:
     void convertAssets(int flags = DEFAULT_VALUE(ConversionFlag, RcAssetFlags));
     void convertActions(int flags = DEFAULT_VALUE(ConversionFlags, RcAssetFlags));

src/rcui/datamodel.cpp

@@ -27,7 +27,9 @@ DataModel::DataModel(const RcCore::RcFile &rcFile, QString language, QObject *pa
     , m_rcFile(rcFile)
     , m_language(std::move(language))
 {
-    Q_ASSERT(m_rcFile.data.contains(m_language));
+    if (!m_language.isEmpty()) {
+        Q_ASSERT(m_rcFile.data.contains(m_language));
+    }
 }
 
 QModelIndex DataModel::index(int row, int column, const QModelIndex &parent) const