From a22b13b773e48b3366fb52703f03b27bddc68a9b Mon Sep 17 00:00:00 2001
From: Mykola Dimura <mykola.dimura@gmail.com>
Date: Mon, 4 May 2020 23:33:23 +0200
Subject: [PATCH] Provide an option to cancel while saving the results table

---
 src/TrajectoriesTreeModel.cpp |  3 ++-
 src/gui/mainwindow.cpp        | 12 +++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/TrajectoriesTreeModel.cpp b/src/TrajectoriesTreeModel.cpp
index 656fb61..28550fe 100644
--- a/src/TrajectoriesTreeModel.cpp
+++ b/src/TrajectoriesTreeModel.cpp
@@ -307,10 +307,11 @@ QString TrajectoriesTreeModel::dumpTabSeparatedData() const
 	QProgressDialog progress("Generating the table...", "Cancel", 0,
 				 indexes.size());
 	progress.setWindowModality(Qt::ApplicationModal);
-	progress.setWindowTitle("Saving results...");
+	progress.setWindowTitle("Generating the table...");
 	progress.setValue(0);
 	for (const auto &idx : indexes) {
 		if (progress.wasCanceled()) {
+			result.clear();
 			break;
 		}
 		TrajectoriesTreeItem *parentItem;
diff --git a/src/gui/mainwindow.cpp b/src/gui/mainwindow.cpp
index 8279853..11e7bb8 100644
--- a/src/gui/mainwindow.cpp
+++ b/src/gui/mainwindow.cpp
@@ -410,6 +410,12 @@ bool MainWindow::exportData(const QString &fileName)
 		return false;
 	}
 	QString s = trajectoriesModel.dumpTabSeparatedData();
+	if (s.isEmpty()) {
+		file.remove();
+		statusBar()->showMessage(tr("Export cancelled").arg(fileName),
+					 5000);
+		return false;
+	}
 	QStringList lines = s.split('\n');
 	QProgressDialog dlg;
 	dlg.setLabelText("Saving the file...");
@@ -417,9 +423,13 @@ bool MainWindow::exportData(const QString &fileName)
 	dlg.setRange(0, lines.size());
 	dlg.setWindowModality(Qt::WindowModal);
 	dlg.show();
-	dlg.setCancelButton(0);
 	QTextStream out(&file);
 	for (int i = 0; i < lines.size(); ++i) {
+		if (dlg.wasCanceled()) {
+			statusBar()->showMessage(
+				tr("Export cancelled").arg(fileName), 5000);
+			return false;
+		}
 		out << lines[i] << "\n";
 		dlg.setValue(i);
 	}