scrollbar.c

MinGUI 可视化程序代码

	{ int scrollOffset=yPos-DesignationW-scrollbar->ScrollbarDragging;
	  int maxScroll_Track=(scrollbar->TrackHeight-scrollbar->ScrollHeight);
	  int maxScroll_Line=(scrollbar->TotalLine-scrollbar->PageKeepLines);
	  int newtopline=scrollOffset*maxScroll_Line/maxScroll_Track;
 	  if(newtopline<0)newtopline=0;
 	  else if(newtopline>maxScroll_Line)newtopline=maxScroll_Line;
	  if(newtopline!=scrollbar->TopLine)
	  {  SendMessage(hWnd,WM_VSCROLL,newtopline,newtopline-scrollbar->TopLine);
	  }
	}
  }
}
//---------------------------------------------------------------------------
void ScrollBar_MouseDown(HWND hWnd,LPARAM LParam)
{ TScrollBar *scrollbar= WndScrollBar(hWnd);
  int xPos=LOWORD(LParam)-WNDPTR(hWnd)->WndRect.left;
  int yPos=HIWORD(LParam)-WNDPTR(hWnd)->WndRect.top;
  if(PointInRect(xPos, yPos, (TRECT *)&scrollbar->Left))
  { int topline;
	if(scrollbar->TrackHeight>0)
	{ if(yPos<scrollbar->Top+DesignationW)
      { ScrollBar_UpdateFlipflopButton(hWnd,scrollbar,1);
		topline=(scrollbar->TopLine>0)?scrollbar->TopLine-1:scrollbar->TopLine;
		SendMessage(hWnd,WM_VSCROLL,topline,-1);
	  }
	  else if(yPos>=scrollbar->Bottom-DesignationW)
	  { ScrollBar_UpdateFlipflopButton(hWnd,scrollbar,2);
	    topline=(scrollbar->TopLine+scrollbar->PageKeepLines<scrollbar->TotalLine)?scrollbar->TopLine+1:scrollbar->TopLine;
	    SendMessage(hWnd,WM_VSCROLL,topline,1);
	  }
	  else if(scrollbar->ScrollHeight>0)
	  { if(yPos<scrollbar->ScrollTop)
		{ if(scrollbar->TopLine>0)
		  { int x1=(scrollbar->ScrollTop-yPos)*(scrollbar->TotalLine-scrollbar->PageKeepLines);
		    int x2=(scrollbar->TrackHeight-scrollbar->ScrollHeight);
		    int step=(x1+x2-1)/x2;
			if(step>scrollbar->TopLine)step=scrollbar->TopLine;
			if(step>0)
			{ SendMessage(hWnd,WM_VSCROLL,scrollbar->TopLine-step,-step);
			}
		  }
        }
		else if(yPos>scrollbar->ScrollTop+scrollbar->ScrollHeight)
		{ if(scrollbar->TopLine+scrollbar->PageKeepLines<scrollbar->TotalLine)
		  { int x1=(yPos-scrollbar->ScrollTop-scrollbar->ScrollHeight)*(scrollbar->TotalLine-scrollbar->PageKeepLines);
		    int x2=(scrollbar->TrackHeight-scrollbar->ScrollHeight);
			int step=(x1+x2-1)/x2;
			if(scrollbar->TopLine+scrollbar->PageKeepLines+step>scrollbar->TotalLine)
			{ step=scrollbar->TotalLine-scrollbar->TopLine-scrollbar->PageKeepLines;
			}
            if(step>0) 
			{  SendMessage(hWnd,WM_VSCROLL,scrollbar->TopLine+step,step);
			}
		  }
		}
	    else if( scrollbar->ScrollHeight< scrollbar->TrackHeight )
		{ scrollbar->ScrollbarDragging=yPos-scrollbar->ScrollTop;
		  if(!scrollbar->ScrollbarDragging)scrollbar->ScrollbarDragging=1;
		}
	  }
    }
    else
	{ int topline=scrollbar->TopLine;
	  if( yPos < ((scrollbar->Top+scrollbar->Bottom)>>1) )
      { ScrollBar_UpdateFlipflopButton(hWnd,scrollbar,1);
	    if(topline>0) topline--;
		SendMessage(hWnd,WM_VSCROLL,topline,-1); 
      }
      else
	  { ScrollBar_UpdateFlipflopButton(hWnd,scrollbar,2);
	    if(topline+scrollbar->PageKeepLines<scrollbar->TotalLine)topline++;
		SendMessage(hWnd,WM_VSCROLL,topline,1);
	  }
    }
  }
}

//---------------------------------------------------------------------------
void ScrollBar_UpdateScroll(HWND hWnd,TScrollBar *scrollbar,BOOL bRepaint)
{ int ScrollTop,ScrollHeight;
  if(bRepaint)
  { ScrollTop=scrollbar->ScrollTop;
    ScrollHeight=scrollbar->ScrollHeight;
  }
  if(scrollbar->TrackHeight>0 && scrollbar->TotalLine>scrollbar->PageKeepLines)
  { /* 确定scroll height 和 positon*/
    
    if(scrollbar->TotalLine<=scrollbar->LinePerPage)
	{ scrollbar->ScrollHeight = scrollbar->TrackHeight - ((scrollbar->TrackHeight*scrollbar->TotalLine/scrollbar->LinePerPage)>>1);
	}
	else
	{ /*scrollbar->ScrollHeight = (scrollbar->TrackHeight*scrollbar->LinePerPage/scrollbar->TotalLine)>>1;*/
	  scrollbar->ScrollHeight = (scrollbar->TrackHeight - scrollbar->TrackHeight*(scrollbar->TotalLine-scrollbar->LinePerPage)/(scrollbar->TotalLine+ScrollHeightAttenuationParam) )>>1;
	}

	if(scrollbar->ScrollHeight<6)scrollbar->ScrollHeight=6;
	if(scrollbar->ScrollHeight<scrollbar->TrackHeight)
    { scrollbar->ScrollTop=scrollbar->Top+DesignationW+(scrollbar->TrackHeight-scrollbar->ScrollHeight)*scrollbar->TopLine/(scrollbar->TotalLine-scrollbar->PageKeepLines);
	}
	else
	{ scrollbar->ScrollTop=scrollbar->Top+DesignationW;
	  scrollbar->ScrollHeight=scrollbar->TrackHeight;
	}
  }
  else
  { scrollbar->ScrollHeight=0;
  }
  if(bRepaint && (ScrollTop!=scrollbar->ScrollTop || ScrollHeight!=scrollbar->ScrollHeight) )
  { HDC dc=GetDC(hWnd);
	ScrollBar_PaintTrack(dc,scrollbar);
	ReleaseDC(dc);
  }
}
//---------------------------------------------------------------------------
void ScrollBar_PaintTrack(HDC dc,TScrollBar *scrollbar)
{ if(scrollbar->TrackHeight>0)
  { GroupOn(dc);

	SetBackColor(dc,CL_BTNFACE);
    EraseBackground(dc,scrollbar->Left,scrollbar->Top+DesignationW,DesignationW,scrollbar->TrackHeight);
	
	if(scrollbar->ScrollHeight>0)
    { DrawRect(dc,scrollbar->Left,scrollbar->ScrollTop,DesignationW,scrollbar->ScrollHeight);
	}

	GroupOff(dc,scrollbar->Left,scrollbar->Top+DesignationW,DesignationW,scrollbar->TrackHeight);
  }
}
//---------------------------------------------------------------------------
void ScrollBar_Repaint(HWND hWnd,HDC dc)
{ TScrollBar *scrollbar=WndScrollBar(hWnd);
  if(scrollbar->TrackHeight>0)
  { int triangleW=DesignationW>>1;
    GroupOn(dc);

    SetBackColor(dc,CL_BTNFACE);
	EraseBackground(dc,scrollbar->Left,scrollbar->Top,DesignationW,DesignationW);
    EraseBackground(dc,scrollbar->Left,scrollbar->Bottom-DesignationW,DesignationW,DesignationW);

	DrawRect(dc,scrollbar->Left,scrollbar->Top,DesignationW,DesignationW);
	DrawLine(dc,scrollbar->Left+4,scrollbar->Top+triangleW+1,scrollbar->Left+triangleW,scrollbar->Top+5);
	DrawLine(dc,scrollbar->Left+DesignationW-4,scrollbar->Top+triangleW+1,scrollbar->Left+triangleW,scrollbar->Top+5);
	DrawLine(dc,scrollbar->Left+5,scrollbar->Top+triangleW+2,scrollbar->Left+triangleW,scrollbar->Top+7);
	DrawLine(dc,scrollbar->Left+DesignationW-5,scrollbar->Top+triangleW+2,scrollbar->Left+triangleW,scrollbar->Top+7);
 
	DrawRect(dc,scrollbar->Left,scrollbar->Bottom-DesignationW	,DesignationW,DesignationW);
	DrawLine(dc,scrollbar->Left+4,scrollbar->Bottom-triangleW-1,scrollbar->Left+triangleW,scrollbar->Bottom-5);
    DrawLine(dc,scrollbar->Left+DesignationW-4,scrollbar->Bottom-triangleW-1,scrollbar->Left+triangleW,scrollbar->Bottom-5);
	DrawLine(dc,scrollbar->Left+5,scrollbar->Bottom-triangleW-2,scrollbar->Left+triangleW,scrollbar->Bottom-7);
    DrawLine(dc,scrollbar->Left+DesignationW-5,scrollbar->Bottom-triangleW-2,scrollbar->Left+triangleW,scrollbar->Bottom-7);
         
	ScrollBar_PaintTrack(dc,scrollbar);
    GroupOff(dc,scrollbar->Left,scrollbar->Top,DesignationW,scrollbar->Bottom-scrollbar->Top);
  }
  else
  { int triangleW=DesignationW>>1;
    int triangleH=DesignationW>>2;
    int triangleOffsetX,i,designationY=(scrollbar->Top+scrollbar->Bottom)>>1;
	int scrollbarHeight=scrollbar->Bottom-scrollbar->Top;
    GroupOn(dc);
    SetBackColor(dc,CL_BTNFACE);
    ClearRect(dc,scrollbar->Left,scrollbar->Top,DesignationW,scrollbarHeight);
    Draw3dOutset(dc,scrollbar->Left,scrollbar->Top,DesignationW,scrollbarHeight);
   
	triangleOffsetX=scrollbar->Left+(DesignationW-triangleW)/2;
    for(i=0;i<triangleH;i++)
	{ DrawHorLine(dc,triangleOffsetX+i,designationY-2-i,triangleW-i-i);
      DrawHorLine(dc,triangleOffsetX+i,designationY+2+i,triangleW-i-i);
	}
    GroupOff(dc,scrollbar->Left,scrollbar->Top,DesignationW,scrollbarHeight);
  }
}
//---------------------------------------------------------------------------