CmdCursor Class Reference

#include <lomse_command.h>

Inheritance diagram for CmdCursor:

Detailed Description

A command for moving the cursor to a new position.

See constructors for details. Each constructor offers a different alternative for specifying the new cursor position.

Public Types
enum	ECursorAction
Public Types inherited from DocCommand
enum	ECmdCursorPolicy
enum	ECmdUndoPolicy
enum	ECmdSelectionPolicy

Public Member Functions
	CmdCursor (ECursorAction cmd, const std::string &name="")
	CmdCursor (ImoId id, const std::string &name="")
	CmdCursor (int measure, int instr, int staff, const std::string &name="")
	CmdCursor (TimeUnits time, int instr, int staff, const std::string &name="")
	CmdCursor (DocCursorState &state, const std::string &name="")
int	get_cursor_update_policy () override
int	get_undo_policy () override
int	get_selection_update_policy () override
Public Member Functions inherited from DocCmdSimple
virtual	~DocCmdSimple ()
bool	is_composite () override
Public Member Functions inherited from DocCommand
virtual	~DocCommand ()
std::string	get_name ()
bool	is_reversible ()
bool	is_recordable ()
std::string	get_error ()

Member Enumeration Documentation

ECursorAction

enum CmdCursor::ECursorAction

This enum describes the posible actions for CmdCursor commands.

Enumerator
k_move_next	Move cursor to the next valid position.
k_move_prev	Move cursor to the previous valid position.
k_enter	When cursor is pointing to a top level element, this action causes the cursor to enter into this top level element and point to first sub-element.
k_exit	When cursor is inside a top level element, this action causes the cursor to move up, out of this top level element, and to point to it.
k_point_to	Move cursor to the specified element.
k_to_state	Move cursor to the specified state.
k_to_measure	When cursor is inside of a music score, this action moves the cursor to the specified measure.
k_to_time	When cursor is inside of a music score, this action moves the cursor to the specified time position.
k_move_up	When cursor is inside of a music score, this action moves the cursor to the previous staff or system, pointing to the nearest note or rest to current vertical position.
k_move_down	When cursor is inside of a music score, this action moves the cursor to the next staff or system, pointing to the nearest note or rest to current vertical position.
k_cursor_dump	This action is restricted for debugging Lomse. Your application should not use it.

Constructor & Destructor Documentation

CmdCursor() [1/5]

CmdCursor::CmdCursor	(	ECursorAction	cmd,
		const std::string &	name = ""
	)

This command moves the cursor to a new position, as specified by parameter cmd.

Parameters

cmd	The action to be performed. It must be one of the following values from enum ECursorAction: k_move_next, k_move_prev, k_enter, k_exit, k_move_up, k_move_down or k_cursor_dump.
name	The displayable name for the command. If not specified or empty will default to one of the following vaues, depending on the requested action: "Cursor: move next", "Cursor: move prev", "Cursor: move up", "Cursor: move down", "Cursor: enter element" or "Cursor: exit element".

Remarks

• After executing the command:
  • the selection will not be changed.
  • the cursor will point to a new position.
• CmdCursor is a transient command, meaning that it is not saved in the undo/redo history and, therefore, undo and redo operations are not available for this command.

Example

bool CommandHandler::process_cursor_key_command(int keyCmd)
{
    //A key has been pressed in the keyboard. The command implied by the
    //pressed key is passed to this method. If it is a cursor command
    //it will be processed here and TRUE is returned.

    if (SpInteractor spInteractor = m_pPresenter->get_interactor(0).lock())
    {
        //cursor is only valid if document edition is enabled
        if (!spInteractor->is_edition_enabled())
            return false;

        switch (keyCmd)
        {
            //cursor keys
            case k_cmd_cursor_move_prev:
                SpInteractor->exec_command( new CmdCursor(CmdCursor::k_move_prev) );
                return true;

            case k_cmd_cursor_move_next:
                SpInteractor->exec_command( new CmdCursor(CmdCursor::k_move_next) );
                return true;

            case k_cmd_cursor_exit:
                SpInteractor->exec_command( new CmdCursor(CmdCursor::k_exit) );
                return true;

            case k_cmd_cursor_enter:
            {
                if (!m_cursor->is_inside_terminal_node())
                {
                    ImoObj* pImo = m_cursor->get_pointee();
                    if (pImo && pImo->is_score())
                    {
                        SpInteractor->exec_command( new CmdCursor(CmdCursor::k_enter) );
                        return true;
                    }
                }
                return false;
            }

            case k_cmd_cursor_to_next_measure:
            case k_cmd_cursor_to_prev_measure:
            case k_cmd_cursor_to_first_measure:
            case k_cmd_cursor_to_last_measure:
            {
                ImoObj* pImo = m_cursor->get_parent_object();
                if (pImo && pImo->is_score())
                {
                    ScoreCursor* pSC =
                        static_cast<ScoreCursor*>(m_cursor->get_inner_cursor());
                    int measure = pSC->measure();
                    if (keyCmd == k_cmd_cursor_to_next_measure)
                        ++measure;
                    else if (keyCmd == k_cmd_cursor_to_prev_measure)
                    {
                        if (measure > 0) --measure;
                    }
                    else if (keyCmd == k_cmd_cursor_to_first_measure)
                        measure = 0;
                    else if (keyCmd == k_cmd_cursor_to_last_measure)
                        measure = 9999999;
                    else;

                    SpInteractor->exec_command( new CmdCursor(measure, -1, -1) );
                    return true;
                }
                return false;
            }

            case k_cmd_cursor_move_up:
            case k_cmd_cursor_move_down:
            {
                ImoObj* pImo = m_cursor->get_parent_object();
                if (pImo && pImo->is_score())
                {
                    if (keyCmd == k_cmd_cursor_move_up)
                        SpInteractor->exec_command( new CmdCursor(CmdCursor::k_move_up) );
                    else
                        SpInteractor->exec_command( new CmdCursor(CmdCursor::k_move_down) );
                    return true;
                }
                return false;
            }

            default:
                return false;
        }
    }
    return false;
}

CmdCursor() [2/5]

CmdCursor::CmdCursor	(	ImoId	id,
		const std::string &	name = ""
	)

This command moves the cursor for pointing to element specified by parameter id.

Parameters

id	The ID of the object that will be pointed by the cursor.
name	The displayable name for the command. If not specified or empty will default to "Cursor: point to".

Remarks

• After executing the command:
  • the selection will not be changed.
  • the cursor will point to a new position.
• CmdCursor is a transient command, meaning that it is not saved in the undo/redo history and, therefore, undo and redo operations are not available for this command.

CmdCursor() [3/5]

CmdCursor::CmdCursor	(	int	measure,
		int	instr,
		int	staff,
		const std::string &	name = ""
	)

When the cursor is inside a music score, this command moves the cursor for pointing to the first element (note, rest, clef, etc.) in the measure specified by parameter measure.

Parameters

measure	The measure to move the cursor to (0..n).
instr	The instrument to move the cursor to. Value -1 means "remain in current instrumnent". For moving to another instrument use instrument number (0 ... num_instruments - 1).
staff	The staff to move the cursor to. Value -1 means "remain in current staff". For moving to another staff use staff number (0 ... num_staves - 1).
name	The displayable name for the command. If not specified or empty will default to "Cursor: jump to new place".

Remarks

• After executing the command:
  • the selection will not be changed.
  • the cursor will point to a new position.
• CmdCursor is a transient command, meaning that it is not saved in the undo/redo history and, therefore, undo and redo operations are not available for this command.

Example

switch (keyCmd)
{
    case k_cmd_cursor_to_next_measure:
    case k_cmd_cursor_to_prev_measure:
    case k_cmd_cursor_to_first_measure:
    case k_cmd_cursor_to_last_measure:
    {
        ImoObj* pImo = m_cursor->get_parent_object();
        if (pImo && pImo->is_score())
        {
            ScoreCursor* pSC =
                static_cast<ScoreCursor*>(m_cursor->get_inner_cursor());
            int measure = pSC->measure();
            if (keyCmd == k_cmd_cursor_to_next_measure)
                ++measure;
            else if (keyCmd == k_cmd_cursor_to_prev_measure)
            {
                if (measure > 0) --measure;
            }
            else if (keyCmd == k_cmd_cursor_to_first_measure)
                measure = 0;
            else if (keyCmd == k_cmd_cursor_to_last_measure)
                measure = 9999999;
            else;

            SpInteractor->exec_command( new CmdCursor(measure, -1, -1) );
            return true;
        }
        return false;
    }
    ...
}

CmdCursor() [4/5]

CmdCursor::CmdCursor	(	TimeUnits	time,
		int	instr,
		int	staff,
		const std::string &	name = ""
	)

When the cursor is inside a music score, this command moves the cursor for pointing to a time position equal than the specified by parameter time.

Parameters

time	The new time position to move the cursor to.
instr	The instrument to move the cursor to. Value -1 means "remain in current instrument". For moving to another instrument use instrument number (0 ... num_instruments - 1).
staff	The staff to move the cursor to. Value -1 means "remain in current staff". For moving to another staff use staff number (0 ... num_staves - 1).
name	The displayable name for the command. If not specified or empty will default to "Cursor: jump to new place".

Remarks

• After executing the command:
  • the selection will not be changed.
  • the cursor will point to a new position.
• CmdCursor is a transient command, meaning that it is not saved in the undo/redo history and, therefore, undo and redo operations are not available for this command.

CmdCursor() [5/5]

CmdCursor::CmdCursor	(	DocCursorState &	state,
		const std::string &	name = ""
	)

This command moves the cursor to the state specified by parameter state.

Parameters

state	The new state for the cursor.
name	The displayable name for the command. If not specified or empty will default to "Cursor: jump to new place".

Remarks

• After executing the command:
  • the selection will not be changed.
  • the cursor will point to a new position.
• CmdCursor is a transient command, meaning that it is not saved in the undo/redo history and, therefore, undo and redo operations are not available for this command.

Member Function Documentation

get_cursor_update_policy()

int CmdCursor::get_cursor_update_policy ( )

inlineoverridevirtual

Returns a value from ECmdCursorPolicy that indicates the update policy followed by this command.

Implements DocCommand.

get_selection_update_policy()

int CmdCursor::get_selection_update_policy ( )

inlineoverridevirtual

Returns a value from ECmdSelectionPolicy that indicates the undo policy followed by this command.

Implements DocCommand.

get_undo_policy()

int CmdCursor::get_undo_policy ( )

inlineoverridevirtual

Returns a value from ECmdUndoPolicy that indicates the undo policy followed by this command.

Implements DocCommand.