diff -r -w -u dialogs.orig/qfiledialog.cpp dialogs/qfiledialog.cpp
--- dialogs.orig/qfiledialog.cpp	2017-10-02 11:43:38.000000000 +0300
+++ dialogs/qfiledialog.cpp	2017-10-19 10:38:38.877450200 +0300
@@ -344,6 +344,7 @@
 {
     Q_D(QFileDialog);
     d->init();
+    d->s_IconProvider = 0;
 }
 
 /*!
@@ -361,6 +362,7 @@
 {
     Q_D(QFileDialog);
     d->init(QUrl::fromLocalFile(directory), filter, caption);
+    d->s_IconProvider = 0;
 }
 
 /*!
@@ -371,6 +373,7 @@
 {
     Q_D(QFileDialog);
     d->init(args.directory, args.filter, args.caption);
+    d->s_IconProvider = 0;
     setFileMode(args.mode);
     setOptions(args.options);
     selectFile(args.selection);
@@ -1981,7 +1984,11 @@
 {
     Q_D(QFileDialog);
     if (!d->usingWidgets())
+    {
+	d->s_IconProvider = provider;
         return;
+    }
+    d->s_IconProvider = 0;
     d->model->setIconProvider(provider);
     //It forces the refresh of all entries in the side bar, then we can get new icons
     d->qFileDialogUi->sidebar->setUrls(d->qFileDialogUi->sidebar->urls());
@@ -2871,6 +2878,8 @@
     Qt::WindowStates preState = q->windowState();
 
     model = new QFileSystemModel(q);
+    if(s_IconProvider)
+	model->setIconProvider(s_IconProvider);
     model->setFilter(options->filter());
     model->setObjectName(QLatin1String("qt_filesystem_model"));
     if (QPlatformFileDialogHelper *helper = platformFileDialogHelper())
diff -r -w -u dialogs.orig/qfiledialog_p.h dialogs/qfiledialog_p.h
--- dialogs.orig/qfiledialog_p.h	2017-10-02 11:43:38.000000000 +0300
+++ dialogs/qfiledialog_p.h	2017-10-19 10:38:38.880458300 +0300
@@ -234,6 +234,7 @@
     // data
     QStringList watching;
     QFileSystemModel *model;
+    QFileIconProvider *s_IconProvider;
 
 #if QT_CONFIG(fscompleter)
     QFSCompleter *completer;