fix default suffixes in save dialog in GNOME, make it more clear that PNG is used (solves #833)

src/qt/addressbookpage.cpp

@@ -7,7 +7,6 @@
 
 #include <QSortFilterProxyModel>
 #include <QClipboard>
-#include <QFileDialog>
 #include <QMessageBox>
 
 AddressBookPage::AddressBookPage(Mode mode, Tabs tab, QWidget *parent) :
@@ -206,10 +205,9 @@ void AddressBookPage::done(int retval)
 void AddressBookPage::exportClicked()
 {
     // CSV is currently the only supported format
-    QString filename = QFileDialog::getSaveFileName(
+    QString filename = GUIUtil::getSaveFileName(
             this,
-            tr("Export Address Book Data"),
-            QDir::currentPath(),
+            tr("Export Address Book Data"), QString(),
             tr("Comma separated file (*.csv)"));
 
     if (filename.isNull()) return;

src/qt/guiutil.cpp

@@ -11,6 +11,8 @@
 #include <QFont>
 #include <QLineEdit>
 #include <QUrl>
+#include <QFileDialog>
+#include <QDesktopServices>
 
 QString GUIUtil::dateTimeStr(qint64 nTime)
 {
@@ -86,3 +88,50 @@ bool GUIUtil::parseBitcoinURL(QString url, SendCoinsRecipient *out)
     QUrl urlInstance(url);
     return parseBitcoinURL(&urlInstance, out);
 }
+
+QString GUIUtil::getSaveFileName(QWidget *parent, const QString &caption,
+                                 const QString &dir,
+                                 const QString &filter,
+                                 QString *selectedSuffixOut)
+{
+    QString selectedFilter;
+    QString myDir;
+    if(dir.isEmpty()) // Default to user documents location
+    {
+        myDir = QDesktopServices::storageLocation(QDesktopServices::DocumentsLocation);
+    }
+    else
+    {
+        myDir = dir;
+    }
+    QString result = QFileDialog::getSaveFileName(parent, caption, myDir, filter, &selectedFilter);
+
+    /* Extract first suffix from filter pattern "Description (*.foo)" or "Description (*.foo *.bar ...) */
+    QRegExp filter_re(".* \\(\\*\\.(.*)[ \\)]");
+    QString selectedSuffix;
+    if(filter_re.exactMatch(selectedFilter))
+    {
+        selectedSuffix = filter_re.cap(1);
+    }
+
+    /* Add suffix if needed */
+    QFileInfo info(result);
+    if(!result.isEmpty())
+    {
+        if(info.suffix().isEmpty() && !selectedSuffix.isEmpty())
+        {
+            /* No suffix specified, add selected suffix */
+            if(!result.endsWith("."))
+                result.append(".");
+            result.append(selectedSuffix);
+        }
+    }
+
+    /* Return selected suffix if asked to */
+    if(selectedSuffixOut)
+    {
+        *selectedSuffixOut = selectedSuffix;
+    }
+    return result;
+}
+

src/qt/guiutil.h

@@ -30,6 +30,21 @@ public:
     // See Bitcoin URL definition discussion here: https://bitcointalk.org/index.php?topic=33490.0
     static bool parseBitcoinURL(const QUrl *url, SendCoinsRecipient *out);
     static bool parseBitcoinURL(QString url, SendCoinsRecipient *out);
+
+    /** Get save file name, mimics QFileDialog::getSaveFileName, except that it appends a default suffix
+        when no suffix is provided by the user.
+
+      @param[in] parent  Parent window (or 0)
+      @param[in] caption Window caption (or empty, for default)
+      @param[in] dir     Starting directory (or empty, to default to documents directory)
+      @param[in] filter  Filter specification such as "Comma Separated Files (*.csv)"
+      @param[out] selectedSuffixOut  Pointer to return the suffix (file type) that was selected (or 0).
+                  Can be useful when choosing the save file format based on suffix.
+     */
+    static QString getSaveFileName(QWidget *parent=0, const QString &caption=QString(),
+                                   const QString &dir=QString(), const QString &filter=QString(),
+                                   QString *selectedSuffixOut=0);
+
 };
 
 #endif // GUIUTIL_H

src/qt/transactionview.cpp

@@ -20,7 +20,6 @@
 #include <QTableView>
 #include <QHeaderView>
 #include <QPushButton>
-#include <QFileDialog>
 #include <QMessageBox>
 #include <QPoint>
 #include <QMenu>
@@ -265,10 +264,9 @@ void TransactionView::changedAmount(const QString &amount)
 void TransactionView::exportClicked()
 {
     // CSV is currently the only supported format
-    QString filename = QFileDialog::getSaveFileName(
+    QString filename = GUIUtil::getSaveFileName(
             this,
-            tr("Export Transaction Data"),
-            QDir::currentPath(),
+            tr("Export Transaction Data"), QString(),
             tr("Comma separated file (*.csv)"));
 
     if (filename.isNull()) return;