Add GUI to import private keys

Addresses GH #1808.

There are several possible future improvements:

 * add a new icon for key import

 * reduce duplication of code between the RPC private key importer and
 the GUI private key importer

 * improving error messages for various error states

1 files changed, 50 insertions, 0 deletions

diff --git a/src/qt/importkeysdialog.h b/src/qt/importkeysdialog.h
new file mode 100644
index 000000000..115e0bd0b
--- /dev/null
+++ b/src/qt/importkeysdialog.h
@@ -0,0 +1,50 @@
+// Copyright (c) 2021 The Dogecoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_QT_OPTIONSDIALOG_H
+#define BITCOIN_QT_OPTIONSDIALOG_H
+class CWallet;
+class CBlockIndex;
+
+#include <QDialog>
+#include <QThread>
+
+class ImportKeysDialog;
+class PlatformStyle;
+
+namespace Ui {
+class ImportKeysDialog;
+}
+
+/** Preferences dialog. */
+class ImportKeysDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit ImportKeysDialog(const PlatformStyle *_platformStyle, QWidget *parent = 0);
+    ~ImportKeysDialog();
+
+Q_SIGNALS:
+    void stopExecutor();
+    void rescanWallet(CWallet*, CBlockIndex*);
+
+private:
+    Ui::ImportKeysDialog *ui;
+    const PlatformStyle *platformStyle;
+    QThread thread;
+
+private Q_SLOTS:
+    /* set OK button state (enabled / disabled) */
+    void setOkButtonState(bool fState);
+    void on_resetButton_clicked();
+    void on_okButton_clicked();
+    void on_cancelButton_clicked();
+    void resetDialogValues();
+
+    /* import a private key */
+    bool importKey();
+};
+
+#endif // BITCOIN_QT_OPTIONSDIALOG_H