File send error message

core.cpp

@@ -517,6 +517,7 @@ void Core::sendFile(int32_t friendId, QString Filename, QString FilePath, long l
     if (fileNum == -1)
     {
         qWarning() << "Core::sendFile: Can't create the Tox file sender";
+        emit fileSendFailed(friendId, Filename);
         return;
     }
     qDebug() << QString("Core::sendFile: Created file sender %1 with friend %2").arg(fileNum).arg(friendId);

core.h

@@ -150,6 +150,8 @@ signals:
     void fileTransferInfo(int FriendId, int FileNum, int64_t Filesize, int64_t BytesSent, ToxFile::FileDirection direction);
     void fileTransferRemotePausedUnpaused(ToxFile file, bool paused);
 
+    void fileSendFailed(int FriendId, const QString& fname);
+
     void avInvite(int friendId, int callIndex, bool video);
     void avStart(int friendId, int callIndex, bool video);
     void avCancel(int friendId, int callIndex);

widget/form/chatform.cpp

@@ -51,6 +51,7 @@ ChatForm::ChatForm(Friend* chatFriend)
     connect(msgEdit, &ChatTextEdit::enterPressed, this, &ChatForm::onSendTriggered);
     connect(micButton, SIGNAL(clicked()), this, SLOT(onMicMuteToggle()));
     connect(chatWidget, &ChatAreaWidget::onFileTranfertInterract, this, &ChatForm::onFileTansBtnClicked);
+    connect(Core::getInstance(), &Core::fileSendFailed, this, &ChatForm::onFileSendFailed);
 }
 
 ChatForm::~ChatForm()
@@ -455,3 +456,11 @@ void ChatForm::onFileTansBtnClicked(QString widgetName, QString buttonName)
     else
         qDebug() << "no filetransferwidget: " << id;
 }
+
+void ChatForm::onFileSendFailed(int FriendId, const QString &fname)
+{
+    if (FriendId != f->friendId)
+        return;
+
+    addSystemInfoMessage("File: \"" + fname + "\" failed to send.", "red");
+}

widget/form/chatform.h

@@ -65,6 +65,7 @@ private slots:
     void onHangupCallTriggered();
     void onCancelCallTriggered();
     void onFileTansBtnClicked(QString widgetName, QString buttonName);
+    void onFileSendFailed(int FriendId, const QString &fname);
 
 private:
     Friend* f;