Make parent window transparent and child window opaque with CEF

On Windows, I'm trying to use CEF (Chromium Embedded Framework) to create a window application with parent window to be transparent and its child window to be opaque (I want to have a rounded corner and an arrow pointing to the status bar in the child window). Something similar to:

enter image description here

I tried to use SetLayeredWindowAttributes to make the parent window transparent but it also makes the child window transparent. Is there a way to make this happen on Windows?

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

If your are willing to sacrifice some performance(it might be minimum depending on you app), you can us offscreen rendering to make a alien control as a browser view in your real window.

– hiitiger
Nov 30 '18 at 7:12

add a comment |

enter image description here

I tried to use SetLayeredWindowAttributes to make the parent window transparent but it also makes the child window transparent. Is there a way to make this happen on Windows?

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

If your are willing to sacrifice some performance(it might be minimum depending on you app), you can us offscreen rendering to make a alien control as a browser view in your real window.

– hiitiger
Nov 30 '18 at 7:12

add a comment |

enter image description here

I tried to use SetLayeredWindowAttributes to make the parent window transparent but it also makes the child window transparent. Is there a way to make this happen on Windows?

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

enter image description here

I tried to use SetLayeredWindowAttributes to make the parent window transparent but it also makes the child window transparent. Is there a way to make this happen on Windows?

windows window adobe chromium-embedded

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

edited Nov 29 '18 at 18:33

trungdinhtrong

1,42311125

asked Nov 21 '18 at 20:37

yijiem

618

asked Nov 21 '18 at 20:37

yijiem

618

asked Nov 21 '18 at 20:37

yijiem

618

If your are willing to sacrifice some performance(it might be minimum depending on you app), you can us offscreen rendering to make a alien control as a browser view in your real window.

– hiitiger
Nov 30 '18 at 7:12

add a comment |

If your are willing to sacrifice some performance(it might be minimum depending on you app), you can us offscreen rendering to make a alien control as a browser view in your real window.

– hiitiger
Nov 30 '18 at 7:12

If your are willing to sacrifice some performance(it might be minimum depending on you app), you can us offscreen rendering to make a alien control as a browser view in your real window.

– hiitiger
Nov 30 '18 at 7:12

add a comment |

1 Answer
1

active

oldest

votes

+100

SetLayeredWindowAttributes needs a color for transparency. Make sure the transparency color is not used by the child window. You can pick a random color, for example RGB(255, 0, 254) and assume the child window is not using it.

If you have no control over the child window, and you can't be sure what colors it might use, then SetWindowRgn is another option to create non-rectangular windows.

The example below shows how to set the region such that the corners are round with a triangle on top.

You can use GDI+ to gain more flexibility for drawing the region, and for anti-aliasing effect so that the borders look more smooth.

#include <Windows.h>



int triangle_height = 30;

int corner_size = 20;

int caption_height = 60;



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_CREATE:

    {

        //create a child button for testing

        CreateWindowW(L"BUTTON", L"Close", WS_CHILD | WS_VISIBLE,

            10, caption_height + 10, 100, 30,

            hwnd, HMENU(100), GetModuleHandle(NULL), NULL);



        RECT rc;

        GetClientRect(hwnd, &rc);



        //create a triangle region

        int w = rc.right;

        int h = rc.bottom;

        int z = triangle_height;

        POINT pt[3];

        pt[0] = { w / 2, 0 };

        pt[1] = { w / 2 - z, z };

        pt[2] = { w / 2 + z, z };

        HRGN htri = CreatePolygonRgn(pt, 3, WINDING);



        //create a round rectangle region

        HRGN hrgn = CreateRoundRectRgn(0, z, w, h - z, corner_size, corner_size);



        //combine the triangle with round rectangle

        CombineRgn(hrgn, htri, hrgn, RGN_OR);



        //set the new region

        SetWindowRgn(hwnd, hrgn, TRUE);



        DeleteObject(htri);

        DeleteObject(hrgn);

        return 0;

    }



    case WM_PAINT:

    {

        PAINTSTRUCT ps;

        HDC hdc = BeginPaint(hwnd, &ps);

        RECT rc = ps.rcPaint;



        //we don't have a standard title bar, paint one here:

        rc.bottom = caption_height;

        SetDCBrushColor(hdc, RGB(80, 80, 80));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //paint the background

        rc = ps.rcPaint;

        rc.top = caption_height;

        SetDCBrushColor(hdc, RGB(240, 240, 240));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //use FrameRgn to paint a border around the region

        HRGN hrgn = CreateRectRgn(0, 0, 0, 0);

        GetWindowRgn(hwnd, hrgn);

        SetDCBrushColor(hdc, RGB(128, 128, 128));

        FrameRgn(hdc, hrgn, (HBRUSH)GetStockObject(DC_BRUSH), 1, 1);

        DeleteObject(hrgn);



        EndPaint(hwnd, &ps);



        return 0;

    }



    case WM_NCHITTEST:

    {

        //we don't have a standard title-bar

        //respond to our custome title-bar manually:

        POINT pt;

        GetCursorPos(&pt);

        ScreenToClient(hwnd, &pt);

        if(pt.y < caption_height)

            return HTCAPTION;

        break;

    }



    case WM_COMMAND:

        if(HIWORD(wparam) == BN_CLICKED)

            if(LOWORD(wparam) == 100)

                SendMessage(hwnd, WM_CLOSE, 0, 0);

        break;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    }



    return DefWindowProc(hwnd, msg, wparam, lparam);

}



int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR, int)

{

    WNDCLASSEXW wcex = { sizeof(wcex) };

    wcex.style = CS_DROPSHADOW;

    wcex.lpfnWndProc = WndProc;

    wcex.hInstance = hInstance;

    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground = NULL;

    wcex.lpszClassName = L"classname";

    RegisterClassExW(&wcex);



    CreateWindowW(wcex.lpszClassName, L"Test", WS_VISIBLE | WS_POPUP,

        200, 200, 600, 400, 0, 0, hInstance, 0);



    MSG msg;

    while(GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

add a comment |

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1 Answer
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1 Answer
1

active

oldest

votes

+100

If you have no control over the child window, and you can't be sure what colors it might use, then SetWindowRgn is another option to create non-rectangular windows.

The example below shows how to set the region such that the corners are round with a triangle on top.

You can use GDI+ to gain more flexibility for drawing the region, and for anti-aliasing effect so that the borders look more smooth.

#include <Windows.h>



int triangle_height = 30;

int corner_size = 20;

int caption_height = 60;



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_CREATE:

    {

        //create a child button for testing

        CreateWindowW(L"BUTTON", L"Close", WS_CHILD | WS_VISIBLE,

            10, caption_height + 10, 100, 30,

            hwnd, HMENU(100), GetModuleHandle(NULL), NULL);



        RECT rc;

        GetClientRect(hwnd, &rc);



        //create a triangle region

        int w = rc.right;

        int h = rc.bottom;

        int z = triangle_height;

        POINT pt[3];

        pt[0] = { w / 2, 0 };

        pt[1] = { w / 2 - z, z };

        pt[2] = { w / 2 + z, z };

        HRGN htri = CreatePolygonRgn(pt, 3, WINDING);



        //create a round rectangle region

        HRGN hrgn = CreateRoundRectRgn(0, z, w, h - z, corner_size, corner_size);



        //combine the triangle with round rectangle

        CombineRgn(hrgn, htri, hrgn, RGN_OR);



        //set the new region

        SetWindowRgn(hwnd, hrgn, TRUE);



        DeleteObject(htri);

        DeleteObject(hrgn);

        return 0;

    }



    case WM_PAINT:

    {

        PAINTSTRUCT ps;

        HDC hdc = BeginPaint(hwnd, &ps);

        RECT rc = ps.rcPaint;



        //we don't have a standard title bar, paint one here:

        rc.bottom = caption_height;

        SetDCBrushColor(hdc, RGB(80, 80, 80));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //paint the background

        rc = ps.rcPaint;

        rc.top = caption_height;

        SetDCBrushColor(hdc, RGB(240, 240, 240));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //use FrameRgn to paint a border around the region

        HRGN hrgn = CreateRectRgn(0, 0, 0, 0);

        GetWindowRgn(hwnd, hrgn);

        SetDCBrushColor(hdc, RGB(128, 128, 128));

        FrameRgn(hdc, hrgn, (HBRUSH)GetStockObject(DC_BRUSH), 1, 1);

        DeleteObject(hrgn);



        EndPaint(hwnd, &ps);



        return 0;

    }



    case WM_NCHITTEST:

    {

        //we don't have a standard title-bar

        //respond to our custome title-bar manually:

        POINT pt;

        GetCursorPos(&pt);

        ScreenToClient(hwnd, &pt);

        if(pt.y < caption_height)

            return HTCAPTION;

        break;

    }



    case WM_COMMAND:

        if(HIWORD(wparam) == BN_CLICKED)

            if(LOWORD(wparam) == 100)

                SendMessage(hwnd, WM_CLOSE, 0, 0);

        break;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    }



    return DefWindowProc(hwnd, msg, wparam, lparam);

}



int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR, int)

{

    WNDCLASSEXW wcex = { sizeof(wcex) };

    wcex.style = CS_DROPSHADOW;

    wcex.lpfnWndProc = WndProc;

    wcex.hInstance = hInstance;

    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground = NULL;

    wcex.lpszClassName = L"classname";

    RegisterClassExW(&wcex);



    CreateWindowW(wcex.lpszClassName, L"Test", WS_VISIBLE | WS_POPUP,

        200, 200, 600, 400, 0, 0, hInstance, 0);



    MSG msg;

    while(GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

add a comment |

+100

If you have no control over the child window, and you can't be sure what colors it might use, then SetWindowRgn is another option to create non-rectangular windows.

The example below shows how to set the region such that the corners are round with a triangle on top.

You can use GDI+ to gain more flexibility for drawing the region, and for anti-aliasing effect so that the borders look more smooth.

#include <Windows.h>



int triangle_height = 30;

int corner_size = 20;

int caption_height = 60;



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_CREATE:

    {

        //create a child button for testing

        CreateWindowW(L"BUTTON", L"Close", WS_CHILD | WS_VISIBLE,

            10, caption_height + 10, 100, 30,

            hwnd, HMENU(100), GetModuleHandle(NULL), NULL);



        RECT rc;

        GetClientRect(hwnd, &rc);



        //create a triangle region

        int w = rc.right;

        int h = rc.bottom;

        int z = triangle_height;

        POINT pt[3];

        pt[0] = { w / 2, 0 };

        pt[1] = { w / 2 - z, z };

        pt[2] = { w / 2 + z, z };

        HRGN htri = CreatePolygonRgn(pt, 3, WINDING);



        //create a round rectangle region

        HRGN hrgn = CreateRoundRectRgn(0, z, w, h - z, corner_size, corner_size);



        //combine the triangle with round rectangle

        CombineRgn(hrgn, htri, hrgn, RGN_OR);



        //set the new region

        SetWindowRgn(hwnd, hrgn, TRUE);



        DeleteObject(htri);

        DeleteObject(hrgn);

        return 0;

    }



    case WM_PAINT:

    {

        PAINTSTRUCT ps;

        HDC hdc = BeginPaint(hwnd, &ps);

        RECT rc = ps.rcPaint;



        //we don't have a standard title bar, paint one here:

        rc.bottom = caption_height;

        SetDCBrushColor(hdc, RGB(80, 80, 80));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //paint the background

        rc = ps.rcPaint;

        rc.top = caption_height;

        SetDCBrushColor(hdc, RGB(240, 240, 240));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //use FrameRgn to paint a border around the region

        HRGN hrgn = CreateRectRgn(0, 0, 0, 0);

        GetWindowRgn(hwnd, hrgn);

        SetDCBrushColor(hdc, RGB(128, 128, 128));

        FrameRgn(hdc, hrgn, (HBRUSH)GetStockObject(DC_BRUSH), 1, 1);

        DeleteObject(hrgn);



        EndPaint(hwnd, &ps);



        return 0;

    }



    case WM_NCHITTEST:

    {

        //we don't have a standard title-bar

        //respond to our custome title-bar manually:

        POINT pt;

        GetCursorPos(&pt);

        ScreenToClient(hwnd, &pt);

        if(pt.y < caption_height)

            return HTCAPTION;

        break;

    }



    case WM_COMMAND:

        if(HIWORD(wparam) == BN_CLICKED)

            if(LOWORD(wparam) == 100)

                SendMessage(hwnd, WM_CLOSE, 0, 0);

        break;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    }



    return DefWindowProc(hwnd, msg, wparam, lparam);

}



int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR, int)

{

    WNDCLASSEXW wcex = { sizeof(wcex) };

    wcex.style = CS_DROPSHADOW;

    wcex.lpfnWndProc = WndProc;

    wcex.hInstance = hInstance;

    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground = NULL;

    wcex.lpszClassName = L"classname";

    RegisterClassExW(&wcex);



    CreateWindowW(wcex.lpszClassName, L"Test", WS_VISIBLE | WS_POPUP,

        200, 200, 600, 400, 0, 0, hInstance, 0);



    MSG msg;

    while(GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

add a comment |

+100

If you have no control over the child window, and you can't be sure what colors it might use, then SetWindowRgn is another option to create non-rectangular windows.

The example below shows how to set the region such that the corners are round with a triangle on top.

You can use GDI+ to gain more flexibility for drawing the region, and for anti-aliasing effect so that the borders look more smooth.

#include <Windows.h>



int triangle_height = 30;

int corner_size = 20;

int caption_height = 60;



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_CREATE:

    {

        //create a child button for testing

        CreateWindowW(L"BUTTON", L"Close", WS_CHILD | WS_VISIBLE,

            10, caption_height + 10, 100, 30,

            hwnd, HMENU(100), GetModuleHandle(NULL), NULL);



        RECT rc;

        GetClientRect(hwnd, &rc);



        //create a triangle region

        int w = rc.right;

        int h = rc.bottom;

        int z = triangle_height;

        POINT pt[3];

        pt[0] = { w / 2, 0 };

        pt[1] = { w / 2 - z, z };

        pt[2] = { w / 2 + z, z };

        HRGN htri = CreatePolygonRgn(pt, 3, WINDING);



        //create a round rectangle region

        HRGN hrgn = CreateRoundRectRgn(0, z, w, h - z, corner_size, corner_size);



        //combine the triangle with round rectangle

        CombineRgn(hrgn, htri, hrgn, RGN_OR);



        //set the new region

        SetWindowRgn(hwnd, hrgn, TRUE);



        DeleteObject(htri);

        DeleteObject(hrgn);

        return 0;

    }



    case WM_PAINT:

    {

        PAINTSTRUCT ps;

        HDC hdc = BeginPaint(hwnd, &ps);

        RECT rc = ps.rcPaint;



        //we don't have a standard title bar, paint one here:

        rc.bottom = caption_height;

        SetDCBrushColor(hdc, RGB(80, 80, 80));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //paint the background

        rc = ps.rcPaint;

        rc.top = caption_height;

        SetDCBrushColor(hdc, RGB(240, 240, 240));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //use FrameRgn to paint a border around the region

        HRGN hrgn = CreateRectRgn(0, 0, 0, 0);

        GetWindowRgn(hwnd, hrgn);

        SetDCBrushColor(hdc, RGB(128, 128, 128));

        FrameRgn(hdc, hrgn, (HBRUSH)GetStockObject(DC_BRUSH), 1, 1);

        DeleteObject(hrgn);



        EndPaint(hwnd, &ps);



        return 0;

    }



    case WM_NCHITTEST:

    {

        //we don't have a standard title-bar

        //respond to our custome title-bar manually:

        POINT pt;

        GetCursorPos(&pt);

        ScreenToClient(hwnd, &pt);

        if(pt.y < caption_height)

            return HTCAPTION;

        break;

    }



    case WM_COMMAND:

        if(HIWORD(wparam) == BN_CLICKED)

            if(LOWORD(wparam) == 100)

                SendMessage(hwnd, WM_CLOSE, 0, 0);

        break;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    }



    return DefWindowProc(hwnd, msg, wparam, lparam);

}



int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR, int)

{

    WNDCLASSEXW wcex = { sizeof(wcex) };

    wcex.style = CS_DROPSHADOW;

    wcex.lpfnWndProc = WndProc;

    wcex.hInstance = hInstance;

    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground = NULL;

    wcex.lpszClassName = L"classname";

    RegisterClassExW(&wcex);



    CreateWindowW(wcex.lpszClassName, L"Test", WS_VISIBLE | WS_POPUP,

        200, 200, 600, 400, 0, 0, hInstance, 0);



    MSG msg;

    while(GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

If you have no control over the child window, and you can't be sure what colors it might use, then SetWindowRgn is another option to create non-rectangular windows.

The example below shows how to set the region such that the corners are round with a triangle on top.

You can use GDI+ to gain more flexibility for drawing the region, and for anti-aliasing effect so that the borders look more smooth.

#include <Windows.h>



int triangle_height = 30;

int corner_size = 20;

int caption_height = 60;



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_CREATE:

    {

        //create a child button for testing

        CreateWindowW(L"BUTTON", L"Close", WS_CHILD | WS_VISIBLE,

            10, caption_height + 10, 100, 30,

            hwnd, HMENU(100), GetModuleHandle(NULL), NULL);



        RECT rc;

        GetClientRect(hwnd, &rc);



        //create a triangle region

        int w = rc.right;

        int h = rc.bottom;

        int z = triangle_height;

        POINT pt[3];

        pt[0] = { w / 2, 0 };

        pt[1] = { w / 2 - z, z };

        pt[2] = { w / 2 + z, z };

        HRGN htri = CreatePolygonRgn(pt, 3, WINDING);



        //create a round rectangle region

        HRGN hrgn = CreateRoundRectRgn(0, z, w, h - z, corner_size, corner_size);



        //combine the triangle with round rectangle

        CombineRgn(hrgn, htri, hrgn, RGN_OR);



        //set the new region

        SetWindowRgn(hwnd, hrgn, TRUE);



        DeleteObject(htri);

        DeleteObject(hrgn);

        return 0;

    }



    case WM_PAINT:

    {

        PAINTSTRUCT ps;

        HDC hdc = BeginPaint(hwnd, &ps);

        RECT rc = ps.rcPaint;



        //we don't have a standard title bar, paint one here:

        rc.bottom = caption_height;

        SetDCBrushColor(hdc, RGB(80, 80, 80));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //paint the background

        rc = ps.rcPaint;

        rc.top = caption_height;

        SetDCBrushColor(hdc, RGB(240, 240, 240));

        FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));



        //use FrameRgn to paint a border around the region

        HRGN hrgn = CreateRectRgn(0, 0, 0, 0);

        GetWindowRgn(hwnd, hrgn);

        SetDCBrushColor(hdc, RGB(128, 128, 128));

        FrameRgn(hdc, hrgn, (HBRUSH)GetStockObject(DC_BRUSH), 1, 1);

        DeleteObject(hrgn);



        EndPaint(hwnd, &ps);



        return 0;

    }



    case WM_NCHITTEST:

    {

        //we don't have a standard title-bar

        //respond to our custome title-bar manually:

        POINT pt;

        GetCursorPos(&pt);

        ScreenToClient(hwnd, &pt);

        if(pt.y < caption_height)

            return HTCAPTION;

        break;

    }



    case WM_COMMAND:

        if(HIWORD(wparam) == BN_CLICKED)

            if(LOWORD(wparam) == 100)

                SendMessage(hwnd, WM_CLOSE, 0, 0);

        break;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    }



    return DefWindowProc(hwnd, msg, wparam, lparam);

}



int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR, int)

{

    WNDCLASSEXW wcex = { sizeof(wcex) };

    wcex.style = CS_DROPSHADOW;

    wcex.lpfnWndProc = WndProc;

    wcex.hInstance = hInstance;

    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground = NULL;

    wcex.lpszClassName = L"classname";

    RegisterClassExW(&wcex);



    CreateWindowW(wcex.lpszClassName, L"Test", WS_VISIBLE | WS_POPUP,

        200, 200, 600, 400, 0, 0, hInstance, 0);



    MSG msg;

    while(GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

edited Dec 6 '18 at 1:35

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

answered Dec 3 '18 at 6:52

Barmak Shemirani

21.5k42145

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

add a comment |

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

Hi Barmak: Your solution works. I tested it as is and I saw the rounded corner box with the arrow. It took me a while to make sure that it works for a parent windows of a CEF window also. In the end that works, too. Thank you. I'm giving you the bounty!

– trungdinhtrong
Dec 4 '18 at 18:16

You are welcome @trungdinhtrong. By the way, you can add [winapi] tag for these types of question to gain more attention. Update: added a thin border around the region with FrameRgn

– Barmak Shemirani
Dec 6 '18 at 1:37

add a comment |

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