LAnimationWindow::IsPreviousFrameAvailable

#include "ltwrappr.h"

L_BOOL LAnimationWindow::IsPreviousFrameAvailable() const

Determines whether there is an existing frame prior to the current frame.

Returns

TRUE

There is a frame prior to the current frame, so you can use LAnimationWindow::MovePreviousFrame.

FALSE

There is not a frame prior to the current frame, so you cannot use LAnimationWindow::MovePreviousFrame.

Comments

You cannot call this function during animation playback.

Required DLLs and Libraries

LTDIS
LTDLG
LTEFX
LTFIL
LTIMG
LTISI
LTSCR
LTTWN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

See Also

Functions:

LAnimationWindow::LAnimationWindow, LAnimationWindow::IsPlaying, LAnimationWindow::GetCurrentIndex, LAnimationWindow::IsPreviousFrameAvailable, LAnimationWindow::IsFirstFrame, LAnimationWindow::IsLastFrame, Class Members

Example

The following example behaves oppositely to PlayAnimation using IsPreviousFrameAvailable 

L_INT LAnimationWindow_IsPreviousFrameAvailableExample(HWND hWndParent)
{
   L_INT nRet;
   LBase::LoadLibraries(LT_ALL_LEADLIB); 
 //make sure all libraries are loaded
   LAnimationWindow MyAnimation;
   WRPUNLOCKSUPPORT();
   MyAnimation.SetFileName(TEXT("C:\\Program Files\\LEAD Technologies, Inc\\LEADTOOLS 15.0\\Images\\eye.gif"));
   nRet = MyAnimation.Load();
   if (nRet==SUCCESS)
   {
      nRet = MyAnimation.MoveLastFrame();
      if(nRet != SUCCESS)
         return nRet;
      MyAnimation.CreateWnd(hWndParent,0, WS_VISIBLE|WS_CHILD|WS_BORDER,0,0,300,300); 
      
      while (MyAnimation.IsPreviousFrameAvailable())
      {
         Sleep(500);
         MyAnimation.MovePreviousFrame();
      }
   }
   else
      return nRet;
   return SUCCESS;
}