qt: rework "receive coins" workflow

src/qt/receiverequestdialog.h

@@ -0,0 +1,40 @@
+#ifndef QRCODEDIALOG_H
+#define QRCODEDIALOG_H
+
+#include <QDialog>
+#include <QImage>
+
+namespace Ui {
+    class ReceiveRequestDialog;
+}
+class OptionsModel;
+
+class ReceiveRequestDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit ReceiveRequestDialog(const QString &addr, const QString &label, quint64 amount, const QString &message, QWidget *parent = 0);
+    ~ReceiveRequestDialog();
+
+    void setModel(OptionsModel *model);
+
+private slots:
+    void on_lnReqAmount_textChanged();
+    void on_lnLabel_textChanged();
+    void on_lnMessage_textChanged();
+    void on_btnSaveAs_clicked();
+
+    void updateDisplayUnit();
+
+private:
+    Ui::ReceiveRequestDialog *ui;
+    OptionsModel *model;
+    QString address;
+    QImage myImage;
+
+    void genCode();
+    QString getURI();
+};
+
+#endif // QRCODEDIALOG_H