这是V1.75版本在Virtual PC上的运行结果，上述应用程序大部分都未实现，不过SDK和API接口都已经完备，后续将陆续补充。

下面是电子时钟程序的运行结果：

代码如下，看是不是与Windows有类似之处？呵呵：

#include "kapi.h"
#include "stdio.h"
#include "math.h"

#define CLK_FACE_COLOR   0x00FFFFFF  //White
#define CLK_SCALE_COLOR  0x0000C0FF  //Same as task band.

//A null routine required by linker when floating point operation is enabled.
void main()
{
}

//A helper local routine used to draw clock scale.
static void DrawClockScale(HANDLE hDC,int cx,int cy,int r)
{
double _minAngle    = PI / 30;   //The angle value between each minute scale.
int startx,starty;               //Start coordinate of clock indicator line.
int endx,endy;                   //End coordinate of clock indicator line.
int innerR1         = r * 9 / 10; //Minute indicator line length only occupy 1/10 of radius.
int innerR2         = r * 4 / 5;  //5 minutes indicator line is 1/5 of radius.

//Draw 60 lines,one for each minutes.
for(int i = 0;i < 60;i ++)
{
if(i % 5 == 0) //5 minutes line.
{
startx = cx + (int)(innerR2 * cos(i * _minAngle));
starty = cy + (int)(innerR2 * sin(i * _minAngle));
}
else
{
startx = cx + (int)(innerR1 * cos(i * _minAngle));
starty = cy + (int)(innerR1 * sin(i * _minAngle));
}
endx = cx + (int)(r * cos(i * _minAngle));
endy = cy + (int)(r * sin(i * _minAngle));
DrawLine(hDC,startx,starty,endx,endy);
}
}

//A local helper routine used to draw clock pointer.
static void _DrawClockPointer(HANDLE hDC,int cx,int cy,int r,int hour,int minute,int second)
{
double angMin,angHur,angSec;  //Angle of hour,minute and second pointer.
int r1 = r * 3 / 4;           //Second pointer's length.
int r2 = r * 2 / 3;           //Minute pointer's length.
int r3 = r / 2;               //Hour pointer's length.
int endx,endy;

angSec = PI * second / 30 - PI / 2;
angMin = PI * minute / 30 - PI / 2 + angSec / 60;
angHur = PI * hour / 6 - PI / 2 + angMin / 60;

//Draw second pointer.
endx = cx + (int)(r1 * cos(angSec));
endy = cy + (int)(r1 * sin(angSec));
DrawLine(hDC,cx,cy,endx,endy);
//Draw minute pointer.
endx = cx + (int)(r2 * cos(angMin));
endy = cy + (int)(r2 * sin(angMin));
DrawLine(hDC,cx,cy,endx,endy);
//Draw hour pointer.
endx = cx + (int)(r3 * cos(angHur));
endy = cy + (int)(r3 * sin(angHur));
DrawLine(hDC,cx,cy,endx,endy);
}

//A helper routine to erase clock's pointers.
static void EraseClockPointer(HANDLE hDC,int cx,int cy,int r,int hour,int minute,int second)
{
HANDLE hOldPen  = NULL;
HANDLE hNewPen  = NULL;

hNewPen = CreatePen(0,1,CLK_FACE_COLOR);
if(NULL == hNewPen)
{
return;
}
hOldPen = SelectPen(hDC,hNewPen);
_DrawClockPointer(hDC,cx,cy,r,hour,minute,second);
//Restore the old pen.
SelectPen(hDC,hOldPen);
DestroyPen(hNewPen);
}

//Draw clock's pointer.
static void DrawClockPointer(HANDLE hDC,int cx,int cy,int r,int hour,int minute,int second)
{
HANDLE hOldPen = NULL;
HANDLE hNewPen = NULL;
HANDLE hOldBrush = NULL;
HANDLE hNewBrush = NULL;

hNewPen = CreatePen(0,1,CLK_SCALE_COLOR);
if(NULL == hNewPen)
{
return;
}
hOldPen = SelectPen(hDC,hNewPen);
_DrawClockPointer(hDC,cx,cy,r,hour,minute,second);
//Restore DC's old pen.
SelectPen(hDC,hOldPen);
DestroyPen(hNewPen);

//Draw the circle in the center of clock face.
hNewBrush = CreateBrush(FALSE,RGB(0x80,0,0));
if(NULL == hNewBrush)
{
return;
}
hOldBrush = SelectBrush(hDC,hNewBrush);
DrawCircle(hDC,cx,cy,10,TRUE);
SelectPen(hDC,hOldPen);
}

//Draw clock face.
static void DrawClockFace(HANDLE hWnd)
{
HANDLE hDC = NULL;
__RECT rect;       //Window client area's rect.
HANDLE hPen = NULL;
HANDLE hBrush = NULL;
HANDLE hOldBrush = NULL;
HANDLE hOldPen = NULL;
int cx,cy,r;

hDC = GetClientDC(hWnd);
if(!GetWindowRect(hWnd,&rect,GWR_INDICATOR_CLIENT))
{
goto __TERMINAL;
}
//Calculate the circle's center coordinate and radius.
cx = (rect.right - rect.left) / 2;
cy = (rect.bottom - rect.top) / 2;
r  = cx > cy ? cy : cx;
r -= 10;  //Keep 10 pixel space between circle and window frame.

//Create the pen and brush object used to draw circle.
hPen = CreatePen(0,1,CLK_SCALE_COLOR);
if(NULL == hPen)
{
goto __TERMINAL;
}
hBrush = CreateBrush(FALSE,CLK_FACE_COLOR);
if(NULL == hBrush)
{
goto __TERMINAL;
}
hOldPen = SelectPen(hDC,hPen);
hOldBrush = SelectBrush(hDC,hBrush);
//Draw the clock face circle now.
DrawCircle(hDC,cx,cy,r,FALSE);
DrawCircle(hDC,cx,cy,r - 1,FALSE);
DrawCircle(hDC,cx,cy,r - 2,FALSE);
DrawCircle(hDC,cx,cy,r - 3,TRUE);
DrawClockScale(hDC,cx,cy,r);  //Draw clock's scale.
//Restore original pen and brush for this window's DC.
SelectPen(hDC,hOldPen);
SelectBrush(hDC,hOldBrush);

__TERMINAL:
if(hPen)
{
DestroyPen(hPen);
}
if(hBrush)
{
DestroyBrush(hBrush);
}
return;
}

//Window procedure of Hello World.
static DWORD HelloWorldProc(HANDLE hWnd,UINT message,WORD wParam,DWORD lParam)
{
static HANDLE hDC = NULL;
static int cx = 0,cy = 0,r = 0;       //Circle's center and radius.
__RECT rect;       //Window's rectangle.
static HANDLE hTimer = NULL;     //Timer handle.
static int hour = 3;
static int minu = 25;
static int secd = 0;

switch(message)
{
case WM_CREATE:    //Will receive this message when the window is created.
hTimer = SetTimer(
(DWORD)hWnd,
250,       //Current version's timer is not accurate since clock chip is not 
          //reinitialized.
NULL,
NULL,
TIMER_FLAGS_ALWAYS);
if(NULL == hTimer)
{
break;
}
GetWindowRect(hWnd,&rect,GWR_INDICATOR_CLIENT);
cx = (rect.right - rect.left) / 2;
cy = (rect.bottom - rect.top) / 2;
r = cx > cy ? cy : cx;
r -= 20;
hDC = GetClientDC(hWnd);
break;
case WM_TIMER:     //Only one timer can be set for one window in current version.
EraseClockPointer(hDC,cx,cy,r,hour,minu,secd);
secd ++;
if(secd == 60)
{
minu ++;
secd = 0;
}
if(minu == 60)
{
hour ++;
minu = 0;
}
if(hour == 12)
{
hour = 0;
}
DrawClockPointer(hDC,cx,cy,r,hour,minu,secd);
break;
case WM_DRAW:
DrawClockFace(hWnd);
DrawClockPointer(hDC,cx,cy,r,hour,minu,secd);
break;
case WM_LBUTTONUP:
//MessageBox(hWnd,"Left button is up.","Notification",MB_OK);
/*
x = (lParam >> 16) & 0x0000FFFF;
y = lParam & 0x0000FFFF;
htResult = HitTest(hWnd,x,y);
if(HT_CLOSEBUTTON == htResult)
{
MessageBox(hWnd,"Close button is clicked.","Notification",MB_OK);
break;
}
if(HT_CAPTION == htResult)
{
MessageBox(hWnd,"Window caption is clicked.","Notification",MB_OK);
break;
}
MessageBox(hWnd,"Neither caption nor close button is clicked.","Notification",MB_OK);*/
break;
case WM_CLOSE:
CloseWindow(hWnd);  //Exit application.
if(NULL != hTimer)
{
CancelTimer(hTimer);
}
PostQuitMessage(0);  //Terminate the kernel thread.
break;
default:
break;
}
return DefWindowProc(hWnd,message,wParam,lParam);
}

//Entry point of Hello World.
DWORD __HCNMain(LPVOID pData)
{
//HANDLE hFrameWnd = (HANDLE)pData;  //pData is the handle of screen window,it is all application's parent window.
MSG msg;
HANDLE hHello = NULL;
__WINDOW_MESSAGE wmsg;

//Create hello world's window.
hHello = CreateWindow(WS_WITHBORDER | WS_WITHCAPTION,
"Analog clock - Version 1.0",
150,
150,
600,
400,
HelloWorldProc,
NULL,//hFrameWnd,
NULL,
0x00800000,
NULL);
if(NULL == hHello)
{
MessageBox(NULL,"Can not create the hello world window.","Error",MB_OK);
goto __TERMINAL;
}
//MessageBox(NULL,"Draw application is running now.","Info",MB_OK);
//CreateButton(NULL,(TCHAR*)0xCCCCCCCC,0xEEEEEEEE,128,128,256,256);

//Message loop of this application.
while(TRUE)
{
if(GetMessage(&msg))
{
switch(msg.wCommand)
{
case KERNEL_MESSAGE_TIMER:
wmsg.hWnd = (HANDLE)msg.dwParam;
wmsg.message = WM_TIMER;
SendWindowMessage(wmsg.hWnd,&wmsg);
break;
case KERNEL_MESSAGE_WINDOW:
DispatchWindowMessage((__WINDOW_MESSAGE*)msg.dwParam);
break;
case KERNEL_MESSAGE_TERMINAL:  //Post by PostQuitMessage.
goto __TERMINAL;
default:
break;
}
}
}

__TERMINAL:
return 0;
}

extern "C"
{
void HCNMain()
{
__HCNMain(NULL);
}
}

Hello China 操作系统的源代码、安装文件、安装说明等，可从下列链接下载：

http://download.csdn.net/detail/hellochina15/4023030

欢迎朋友们下载试用。如有任何技术问题，请与作者联系。

联系信息：

作者：辛庆祥，操作系统开发爱好者，目前正从事开源操作系统Hello China的开发，曾以蓝枫叶为笔名，出版《嵌入式操作系统：设计与实现》一书。Hello China开发QQ群：38467832   新浪微博：http://weibo.com/2196920292