How to show updated variable to a window

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How to show updated variable to a window

How to show updated variable to a window?

I have window running that shows one variable. I would like to increase that variable every few seconds and update it on a window. I don't know how to do it. I can print that variable once using TextOut, but once it compiles, I can't update it. As you can see, I tried in APIENTRY WinMain, but it only goes once and doesn't loop and update it. Variable that I want to increase in a loop is "test". Can you please help me?

This is most of code. Only thing above this are two functions that I use and #include's.


	LRESULT CALLBACK WndProc(HWND hwndMain, UINT uMsg, WPARAM wParam, LPARAM lParam);


	
	INT APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
	{
		for (int i = 0; i < 50; i++){
			inputDat();
			data();

			test += 1;
			Sleep(1000);

			WNDCLASSEX windowClass;
			windowClass.lpszClassName = "Main Class";
			windowClass.cbClsExtra = NULL;
			windowClass.cbWndExtra = NULL;
			windowClass.cbSize = sizeof(WNDCLASSEX);
			windowClass.hbrBackground = (HBRUSH)CreateSolidBrush(RGB(247, 247, 247));
			windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
			windowClass.hIcon = LoadIcon(NULL, MAKEINTRESOURCE(IDI_APPLICATION));
			windowClass.hIconSm = (HICON)LoadImage(NULL, MAKEINTRESOURCE(IDI_APPLICATION), IMAGE_ICON, 16, 16, NULL);
			windowClass.hInstance = hInstance;
			windowClass.lpfnWndProc = WndProc;
			windowClass.lpszMenuName = NULL;
			windowClass.style = CS_VREDRAW | CS_HREDRAW;
			RegisterClassEx(&windowClass);

			HWND Main = CreateWindowEx(NULL, "Main Class", "Weather station report",
				WS_OVERLAPPEDWINDOW | WS_VISIBLE,
				100, 100, 500, 500,
				NULL, NULL, hInstance, NULL);


			if (!Main)
				return(0);


			MSG msg;
			while (GetMessage(&msg, NULL, 0, 0))
			{
				TranslateMessage(&msg);
				DispatchMessage(&msg);
			}

			return msg.wParam;
			
			UpdateWindow(Main);
			
		}
	}


	LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
	{
		
		char *mtr;
		mtr = new char[384];
		FILE *drd;
		FILE *bbd;

		drd = fopen("bin.txt", "r");
		fread(mtr, 1, 412, drd);
		fclose(drd);
		

		for (int g = 28; g < 412; g += 52){
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 1;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 2;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 3;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 4;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 5;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 6;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 7;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 8;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 9;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xA;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xB;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0xC;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 0xD;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xE;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xF;
		}


		for (int g = 32; g < 412; g += 52){
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 1;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 2;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 3;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 4;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 5;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 6;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 7;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 8;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 9;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xA;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xB;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0xC;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 0xD;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xE;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xF;
		}

		for (int g = 36; g < 412; g += 52){
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 1;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 2;
			if (mtr[g] == 48 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 3;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 4;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 5;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 6;
			if (mtr[g] == 48 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 7;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 8;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 9;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xA;
			if (mtr[g] == 49 && mtr[g + 1] == 48 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xB;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 48)
				fbd[g] = 0xC;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 48 && mtr[g + 3] == 49)
				fbd[g] = 0xD;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 48)
				fbd[g] = 0xE;
			if (mtr[g] == 49 && mtr[g + 1] == 49 && mtr[g + 2] == 49 && mtr[g + 3] == 49)
				fbd[g] = 0xF;
		}


		int temp = fbd[28] * 10 + fbd[32]-30;
		
		int hum = fbd[80] * 10 + fbd[84] ;
		
		

		TCHAR V1[100];
		TCHAR V2[100];
		TCHAR V3[100];

		TCHAR V4[100];
		TCHAR V5[100];
		TCHAR V6[100];

		TCHAR V7[100];
		TCHAR V8[100];
	

		switch (message)
		{
		case WM_CREATE:
		{

		}

		case WM_COMMAND:
		{

		}
		break;

	
		case WM_PAINT:
		{
			
			PAINTSTRUCT Ps;
			HDC hdc;
			hdc = BeginPaint(hwnd, &Ps);
			SetBkColor(hdc, RGB(255, 255, 255));
			SetTextColor(hdc, RGB(0, 0, 0));
		
			TextOut(hdc, 10, 10, "Temperatura",11);
			test += 1;
			TextOut(hdc, 200, 10, V3, wsprintf(V3, "%d", test));

			TextOut(hdc, 100, 10, V1, wsprintf(V1, "%d", temp));
		
			TextOut(hdc, 10, 30, "Vlaznost", 8);
			TextOut(hdc, 100, 30, V2, wsprintf(V2, "%d", hum));
			

			EndPaint(hwnd, &Ps);
		

		}
		break;
		case WM_CLOSE:
		{
			PostQuitMessage(WM_QUIT);
		}
		break;
		default:
			return(DefWindowProc(hwnd, message, wParam, lParam));
		}
		
		
		return(0);


	}

Last edited on

I14R10 (24)

I figured out that it works as long as I am constantly resizing window. So I need to send a msg to tell it to update it.

modoran (2077)

You can use a timer with SetTimer and process WM_TIMER message. Also, your code is a bit inneficient as written.

I14R10 (24)

That fixes that problem with no update on window, but I still have to put my functions inside WM_PAINT because they don't get updated in WinMain. Do I really have to do that because sometimes it encounters breakpoint? I would rather like to put my functions inside WinMain. But as I said the problem there is that I can't get any loop to work. They all go only once.

modoran (2077)

Call InvalidateRect to force WM_PAINT to be sent. You can't do what you want directly inside WinMain. No way.
https://msdn.microsoft.com/en-us/library/windows/desktop/dd145002%28v=vs.85%29.aspx

jheard901 (90)

~~Wow, and I was just about to post a thread asking the same question "How to display variables through the status bar?"~~

Scrap that, I misread. This is about updating a window, not the status bar.

Last edited on

I14R10 (24)

Thank you modoran. That worked!

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