edit_box_msg.h

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/* -*- c++ -*- */
/*
 * Copyright 2016 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */
 
#ifndef INCLUDED_QTGUI_EDIT_BOX_MSG_H
#define INCLUDED_QTGUI_EDIT_BOX_MSG_H
 
#include <gnuradio/block.h>
#include <gnuradio/qtgui/api.h>
#include <gnuradio/qtgui/qtgui_types.h>
#include <qapplication.h>
 
namespace gr {
namespace qtgui {
 
/*!
 * \brief Create a QT Edit Box widget where the value is posted as a message.
 * \ingroup qtgui_blk
 *
 * \details
 * This block creates a QT Edit Box widget that manages data
 * through message passing interfaces. The 'msg' output port
 * produces messages based on the text in the edit box and the
 * data type set by the \p type argument (see
 * gr::qtgui::data_type_t). The data types are checked, and WARN
 * log messages are produced when the data is in the wrong
 * format. Not all errors are explicitly checked for, only that
 * conversions happen correctly. Failures are either produces as
 * log messages or the action is simply silently dropped.
 *
 * The value of the edit boxes can be programmatically updated
 * through the 'val' input message port. It is also checked for
 * the correct data type.
 *
 * The \p is_pair argument to the constructor determines if the
 * edit box handles a key:value pair. If set to True, two edit
 * boxes are created with the left for the key and right for the
 * value. The key is always assumed to be a string and the value
 * is restricted by the data type setting as above.
 *
 * The block can take a default value. Because the block is
 * capable of handling multiple different data types, we enter the
 * default value as a string in the same way we expect the user to
 * enter it into the Value edit box of the widget. We convert this
 * default exactly the same way we convert the user-entered text
 * in the edit box. See the next paragraph for an explanation for
 * how to handle complex numbers.
 *
 * Complex numbers are currently handled a bit differently than
 * expected. Because we use the std iostream for complex, complex numbers MUST
 * be in the form "(a,b)" to represent "a + jb". Note that you cannot even have
 * a space after the comma, so "(1.23,10.56)" is correct while "(1.23, 10.56)"
 * will not parse.
 *
 * The 'static' mode prevents the user from changing the data type
 * or the key used in the widget. If also in 'pair' mode, the key
 * is not displayed and so must be set in the constructor. It is
 * an error if using static and pair modes with no default key
 * set.
 *
 * Message Ports:
 *
 * - msg (output):
 *       Produces a PMT message from the data in the edit box. It
 *       is packaged in the PMT container determined by the \p
 *       type argument to the ctor. If the data in the box is not of
 *       the correct type and the conversion fails, the block
 *       produces a log WARN message but does nothing else with
 *       the data. If the \p is_pair flag is set on this block, it
 *       will produce a PMT pair object where the key (car) is
 *       assumed to be a string and the value (cdr) is determined
 *       by \p type.
 *
 * - val (input):
 *       Accepts messages to update the value in the edit
 *       boxes. The messages, as PMTs, are first checked to make
 *       sure that they are the correct type (integer, float,
 *       string, or complex), and unpacks them and converts them
 *       to QStrings to display in the edit box. When using \p
 *       is_pair, the PMT is checked to make sure it is a PMT
 *       pair. Then the key (car) is extracted as a string before
 *       the value (cdr) is processed based on the set data type
 *       of the box.
 */
class QTGUI_API edit_box_msg : virtual public block
{
public:
    // gr::qtgui::edit_box_msg::sptr
    typedef std::shared_ptr<edit_box_msg> sptr;
 
    /*!
     * \brief Constructs the Edit box block.
     *
     * \param type the data type of data in the value box.
     * \param value the default value of the message. This is
     *        entered as a string regardless of the type and
     *        converted internally -- much like how the block
     *        extracts the value from the edit box and converts it.
     * \param label a label to identify the box on screen.
     * \param is_pair if we are using a key:value pair.
     * \param is_static sets the key edit box as a static text box
     *                  (cannot be edited live).
     * \param key Set the key used in a key:value pair message.
     * \param parent a QWidget parent in the QT app.
     */
    static sptr make(gr::qtgui::data_type_t type,
                     const std::string& value = "",
                     const std::string& label = "",
                     bool is_pair = true,
                     bool is_static = true,
                     const std::string& key = "",
                     QWidget* parent = NULL);
 
    virtual void exec_() = 0;
    virtual QWidget* qwidget() = 0;
 
    QApplication* d_qApplication;
};
 
} /* namespace qtgui */
} /* namespace gr */
 
#endif /* INCLUDED_QTGUI_EDIT_BOX_MSG_H */