How to change the background of a readable edit control

Hey,
I am working on this project where I need to update an edit box every couple of seconds with a status and based on the status I need to change the color of the background to a particular color.I am able to update the edit box with the status but is clueless on how to update background color.I have read some info on line about this but is confused. I followed one sample until it mentioned about doing something to your ID_CTLCOLOR handle, I am confused about where this handle is and what is it. Any help will be greatly appreciated.

Thanks In Advance
An example I just knocked up in Codeblocks.
One thing to note is the trapping of the WM_CTLCOLOREDIT windows message.


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
#include <windows.h>
#include <commctrl.h>
#include <tchar.h>

//********************************************************************************
//Some IDs defines for the edit boxes
#define IDC_EDIT1 100
#define IDC_EDIT2 101
//*******************************************************************************

/*  Declare Windows procedure  */
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);

/*  Make the class name into a global variable  */
char szClassName[ ] = "CodeBlocksWindowsApp";

int WINAPI WinMain (HINSTANCE hThisInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR lpszArgument,
                     int nCmdShow)
{
    HWND hwnd;               /* This is the handle for our window */
    MSG messages;            /* Here messages to the application are saved */
    WNDCLASSEX wincl;        /* Data structure for the windowclass */

    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;      /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                 /* Catch double-clicks */
    wincl.cbSize = sizeof (WNDCLASSEX);

    /* Use default icon and mouse-pointer */
    wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
    wincl.lpszMenuName = NULL;                 /* No menu */
    wincl.cbClsExtra = 0;                      /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                      /* structure or the window instance */
    /* Use Windows's default colour as the background of the window */
    wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;

    /* Register the window class, and if it fails quit the program */
    if (!RegisterClassEx (&wincl))
        return 0;

    /* The class is registered, let's create the program*/
    hwnd = CreateWindowEx (
           0,                   /* Extended possibilites for variation */
           szClassName,         /* Classname */
           "Code::Blocks Template Windows App",       /* Title Text */
           WS_OVERLAPPEDWINDOW, /* default window */
           CW_USEDEFAULT,       /* Windows decides the position */
           CW_USEDEFAULT,       /* where the window ends up on the screen */
           544,                 /* The programs width */
           375,                 /* and height in pixels */
           HWND_DESKTOP,        /* The window is a child-window to desktop */
           NULL,                /* No menu */
           hThisInstance,       /* Program Instance handler */
           NULL                 /* No Window Creation data */
           );

    /* Make the window visible on the screen */
    ShowWindow (hwnd, nCmdShow);

    /* Run the message loop. It will run until GetMessage() returns 0 */
    while (GetMessage (&messages, NULL, 0, 0))
    {
        /* Translate virtual-key messages into character messages */
        TranslateMessage(&messages);
        /* Send message to WindowProcedure */
        DispatchMessage(&messages);
    }

    /* The program return-value is 0 - The value that PostQuitMessage() gave */
    return messages.wParam;
}


/*  This function is called by the Windows function DispatchMessage()  */

LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    static HBRUSH hBrush1, hBrush2;
    static HWND hEdit1, hEdit2;

    switch (message)                  /* handle the messages */
    {

    case WM_CREATE:
        //***********************************************************************************************
        //Create 2 Edit controls
        hEdit1 =CreateWindow(WC_EDIT, _TEXT("Some Text"), WS_CHILD|WS_VISIBLE|WS_BORDER|ES_LEFT, 20, 20, 250, 25,
                     hwnd, (HMENU)IDC_EDIT1,GetModuleHandle(NULL), NULL );
        hEdit2 = CreateWindow(WC_EDIT, _TEXT("Some Text"), WS_CHILD|WS_VISIBLE|WS_BORDER|ES_LEFT, 20, 50, 250, 25,
                     hwnd, (HMENU)IDC_EDIT2,GetModuleHandle(NULL), NULL );
        //and  create some brushes
        hBrush1 =CreateSolidBrush(RGB(255,0,0));
        hBrush2 = CreateSolidBrush( RGB(0,0,255));

        //**********************************************************************************************
        return 0;
        break;


        //***************************************************************
        //Now do the control colours for the edit boxes
        //We will do one RED and the other blue
    case WM_CTLCOLOREDIT:
        SetBkMode( (HDC)wParam, TRANSPARENT);

        if ((HWND)lParam ==  hEdit1)
            return (LRESULT)hBrush1;
        else if ( (HWND)lParam == hEdit2)
            return (LRESULT)hBrush2;
        else
        return DefWindowProc (hwnd, message, wParam, lParam);
        break;
        //***********************************************************************



        case WM_DESTROY:
            //*************************************************************
            //Remember to clean up!!!!!!!!!!!!!!!!!!!
            DeleteObject( hBrush1);
            DeleteObject( hBrush2);
            //*************************************************************8

            PostQuitMessage (0);       /* send a WM_QUIT to the message queue */
            break;
        default:                      /* for messages that we don't deal with */
            return DefWindowProc (hwnd, message, wParam, lParam);
    }

    return 0;
}
Last edited on
Topic archived. No new replies allowed.