How to prevent some action in app using winapi? - c++

Question

I would like to prevent some action in my app using winapi for example I would like to block moving my window app. How can I do this?
I try this:
if( pWindowsMessage->message == WM_MOVING )
{
return 1;
}
else if(pWindowsMessage->message == WM_MOVE)
{
return 1;
}
But it doesn't work.
Other example: How to prevent close the window?
if( pWindowsMessage->message == WM_CLOSE )
{
return 1;
}
It works. But is it a good solution?
Of course the first and the second example are in the function which get messages.

Answer 1

You can block messages in different areas by handling WM_NCLBUTTONDOWN messages.
And According to WM_NCHITTEST,we can handle events in different regions.
Here is a sample:
#include <Windows.h>
#include <cassert>
#include <cstdlib>
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT("hello windows");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;
wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = WndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = szAppName;
if (!RegisterClass(&wndclass))
{
MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);
}
hwnd = CreateWindow(szAppName,
TEXT("the hello program"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL);
ShowWindow(hwnd, iCmdShow);
UpdateWindow(hwnd);
while (GetMessageW(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessageW(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
case WM_DESTROY:
PostQuitMessage(0);
break;
case WM_NCLBUTTONDOWN:
if (wParam == HTCAPTION || (wParam >= HTLEFT && wParam < HTBORDER))
return 0;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}