GUI C++ - Paint multiple lines? (Beginner question) - c++

Question

I want to explore C++ GUI coding.
I downloaded the example below and wanted to modify the output highlighted with: "<---------------". I know its a very stupid question but my goal is to learn the concept of GUI with C++ by doing.
What and why I have to do in order to add the second line "Test. 3, 2, 1.". My approach didn't work and only results the first line.
// HelloWindowsDesktop.cpp
// compile with: /D_UNICODE /DUNICODE /DWIN32 /D_WINDOWS /c
#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <tchar.h>
// Global variables
// The main window class name.
static TCHAR szWindowClass[] = _T("DesktopApp");
// The string that appears in the application's title bar.
static TCHAR szTitle[] = _T("Test Title");
HINSTANCE hInst;
// Forward declarations of functions included in this code module:
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int CALLBACK WinMain(
_In_ HINSTANCE hInstance,
_In_opt_ HINSTANCE hPrevInstance,
_In_ LPSTR lpCmdLine,
_In_ int nCmdShow
)
{
WNDCLASSEX wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, IDI_APPLICATION);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION);
if (!RegisterClassEx(&wcex))
{
MessageBox(NULL,
_T("Call to RegisterClassEx failed!"),
_T("Test Program 00"),
NULL);
return 1;
}
// Store instance handle in our global variable
hInst = hInstance;
// The parameters to CreateWindow explained:
// szWindowClass: the name of the application
// szTitle: the text that appears in the title bar
// WS_OVERLAPPEDWINDOW: the type of window to create
// CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)
// 500, 100: initial size (width, length)
// NULL: the parent of this window
// NULL: this application does not have a menu bar
// hInstance: the first parameter from WinMain
// NULL: not used in this application
HWND hWnd = CreateWindow(
szWindowClass,
szTitle,
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
500, 100,
NULL,
NULL,
hInstance,
NULL
);
if (!hWnd)
{
MessageBox(NULL,
_T("Call to CreateWindow failed!"),
_T("Test Program 01"),
NULL);
return 1;
}
// The parameters to ShowWindow explained:
// hWnd: the value returned from CreateWindow
// nCmdShow: the fourth parameter from WinMain
ShowWindow(hWnd,
nCmdShow);
UpdateWindow(hWnd);
// Main message loop:
MSG msg;
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return (int)msg.wParam;
}
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.
//
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
TCHAR greeting[] = _T("Test. 1, 2, 3.");
PAINTSTRUCT ps1;
HDC hdc1;
TCHAR greeting1[] = _T("Test. 3, 2, 1.");
switch (message)
{
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);
// Here your application is laid out.
// For this introduction, we just print out "Hello, Windows desktop!" <-----------------------------------------------
// in the top left corner.
TextOut(hdc,
5, 5,
greeting, _tcslen(greeting));
EndPaint(hWnd, &ps);
// CAN ONLY PAINT ONE???
hdc1 = BeginPaint(hWnd, &ps1);
TextOut(hdc1,
6, 6,
greeting1, _tcslen(greeting1));
// End application-specific layout section.
EndPaint(hWnd, &ps1);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
break;
}
return 0;
}