Timer operations
[Window creating/destroying]

Defines

• #define SetTimer(hwnd, id, speed)   SetTimerEx(hwnd, id, speed, NULL)

  The backward compatibility version of SetTimerEx.
  

• #define ResetTimer(hwnd, id, speed)   ResetTimerEx(hwnd, id, speed, (TIMERPROC)0xFFFFFFFF)

  The backward compatibility version of ResetTimerEx.
  

Typedefs

• typedef BOOL(* TIMERPROC )(HWND, int, DWORD)

  Type of the timer callback procedure.
  

Functions

• MG_EXPORT BOOL GUIAPI SetTimerEx (HWND hWnd, int id, unsigned int speed, TIMERPROC timer_proc)

  Creates a timer with the specified timeout value.
  

• MG_EXPORT int GUIAPI KillTimer (HWND hWnd, int id)

  Destroys a timer.
  

• MG_EXPORT BOOL GUIAPI ResetTimerEx (HWND hWnd, int id, unsigned int speed, TIMERPROC timer_proc)

  Adjusts a timer with a different timeout value or different timer callback procedure.
  

• MG_EXPORT unsigned int GUIAPI GetTickCount (void)

  Retrieves the tick counts that have elapsed since MiniGUI was started.
  

• MG_EXPORT BOOL GUIAPI IsTimerInstalled (HWND hWnd, int id)

  Determines whether a timer is installed.
  

• MG_EXPORT BOOL GUIAPI HaveFreeTimer (void)

  Determines whether there is any free timer slot in the system.
  

---

Define Documentation

#define ResetTimer	(	hwnd,
		id,
		speed		)	ResetTimerEx(hwnd, id, speed, (TIMERPROC)0xFFFFFFFF)

The backward compatibility version of ResetTimerEx.

See also:

ResetTimerEx

Definition at line 7299 of file window.h.

#define SetTimer	(	hwnd,
		id,
		speed		)	SetTimerEx(hwnd, id, speed, NULL)

The backward compatibility version of SetTimerEx.

See also:

SetTimerEx

Definition at line 7252 of file window.h.

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Typedef Documentation

typedef BOOL(* TIMERPROC)(HWND, int, DWORD)

Type of the timer callback procedure.

This is the prototype of the callback procedure of a timer created by SetTimerEx. MiniGUI will call the timer procedure instead of sending MSG_TIMER message.

If the return value of a timer procedure is FALSE, the timer will be killed by MiniGUI automatically. This can be used to implement a one-shot timer.

See also:

SetTimerEx

Definition at line 7208 of file window.h.

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Function Documentation

unsigned int GUIAPI GetTickCount

(

void

)

Retrieves the tick counts that have elapsed since MiniGUI was started.

This function retrieves the tick counts that have elapsed since MiniGUI was started. It is limited to the resolution of the system timer, i.e. for a general Linux box, the returned tick count value is in unit of 10ms.

Returns:

The tick counts value that have elapsed since MiniGUI was started.

BOOL GUIAPI HaveFreeTimer

(

void

)

Determines whether there is any free timer slot in the system.

This function determines whether there is any free timer slot in the system.

Returns:

TRUE for yes, otherwise FALSE.

See also:

IsTimerInstalled

BOOL GUIAPI IsTimerInstalled	(	HWND	hWnd,
		int	id
	)

Determines whether a timer is installed.

This function determines whether a timer with identifier id of a window hwnd has been installed.

Parameters:

	hWnd	The window owns the timer.
	id	The identifier of the timer.

Returns:

TRUE for installed, otherwise FALSE.

See also:

SetTimer, HaveFreeTimer

int GUIAPI KillTimer	(	HWND	hWnd,
		int	id
	)

Destroys a timer.

This function destroys the specified timer id.

Parameters:

	hWnd	The window owns the timer.
	id	The identifier of the timer. If id equals or is less than 0, this function will kill all timers in the system.

Returns:

The number of actually killed timer.

See also:

SetTimer

BOOL GUIAPI ResetTimerEx	(	HWND	hWnd,
		int	id,
		unsigned int	speed,
		TIMERPROC	timer_proc
	)

Adjusts a timer with a different timeout value or different timer callback procedure.

This function resets a timer with the specified timeout speed value.

Parameters:

	hWnd	The window owns the timer.
	id	The identifier of the timer.
	speed	The new timeout value.
	timer_proc	The new timer callback procedure. If timer_proc is 0xFFFFFFFF, the setting of timer callback procedure will not changed.

Returns:

TRUE on success, FALSE on error.

See also:

SetTimerEx

BOOL GUIAPI SetTimerEx	(	HWND	hWnd,
		int	id,
		unsigned int	speed,
		TIMERPROC	timer_proc
	)

Creates a timer with the specified timeout value.

This function creates a timer with the specified timeout value speed. Note that the timeout value is in unit of 10 ms. When the timer expires, an MSG_TIMER message will be send to the window hWnd if timer_proc is NULL, otherwise MiniGUI will call timer_proc by passing hWnd, id, and the tick count when this timer had expired to this callback procedure.

Parameters:

	hWnd	The window receives the MSG_TIMER message. If timer_proc is not NULL, MiniGUI will call timer_proc instead sending MSG_TIMER message to this window. If you use timer callback procedure, hWnd can be any value you can pass.
	id	The identifier of the timer, will be passed to the window with MSG_TIMER message as the first parameter of the message.
	speed	The timeout value of the timer. Note that the timeout value is in unit of 10 ms.
	timer_proc	The timer callback procedure. If this argument is NULL, MiniGUI will send MSG_TIMER to the window procedure of hWnd.

Returns:

TRUE on success, FALSE on error.

See also:

SetTimer, ResetTimerEx, KillTimer, MSG_TIMER

Note:

You should set, reset, and kill a timer in the same thread if your MiniGUI is configured as MiniGUI-Threads.

Example:

/*
 * A typical handling of timer.
 */
int FlyingGUIWinProc (HWND hWnd, int message, WPARAM wParam, LPARAM lParam)
{
    switch (message) {
        case MSG_CREATE:
        /* create a timer which expires every 100 ms, and whose id is 100. */
#ifdef _MGTIMER_UNIT_10MS
            SetTimer (hWnd, 100, 10);
#else
            SetTimer (hWnd, 100, 100);
#endif
        break;

        /* handling the MSG_TIMER message. */
        case MSG_TIMER:
            if (wParam == 100) /* if it is the timer whose id is 100. */
                InvalidateRect (hWnd, NULL, FALSE);
        break;

        case MSG_CLOSE:
            /* kill the timer whose id is 100. */
            KillTimer (hWnd, 100);
            DestroyMainWindow (hWnd);
            PostQuitMessage (hWnd);
        return 0;
    }

    return DefaultMainWinProc(hWnd, message, wParam, lParam);
}