host/NativeSubWindow_win32.cpp

/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "NativeSubWindow.h"

struct SubWindowUserData {
    SubWindowRepaintCallback repaint_callback;
    void* repaint_callback_param;
};

static LRESULT CALLBACK subWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    if (uMsg == WM_PAINT) {
        auto user_data =
            (SubWindowUserData*)GetWindowLongPtr(hwnd, GWLP_USERDATA);
        if (user_data && user_data->repaint_callback) {
            user_data->repaint_callback(user_data->repaint_callback_param);
        }
    } else if (uMsg == WM_NCDESTROY) {
        SubWindowUserData* user_data =
            (SubWindowUserData*)GetWindowLongPtr(hwnd, GWLP_USERDATA);
        delete user_data;
    }
    return DefWindowProcA(hwnd, uMsg, wParam, lParam);
}

EGLNativeWindowType createSubWindow(FBNativeWindowType p_window,
                                    int x, int y,int width, int height, float dpr,
                                    SubWindowRepaintCallback repaint_callback,
                                    void* repaint_callback_param, int hideWindow){
    static const char className[] = "subWin";

    WNDCLASSA wc = {};
    if (!GetClassInfoA(GetModuleHandle(NULL), className, &wc)) {
        wc.style =  CS_OWNDC | CS_HREDRAW | CS_VREDRAW;// redraw if size changes
        wc.lpfnWndProc = &subWindowProc;               // points to window procedure
        wc.cbWndExtra = sizeof(void*) ;                // save extra window memory
        wc.lpszClassName = className;                  // name of window class
        RegisterClassA(&wc);
    }

    EGLNativeWindowType ret = CreateWindowExA(
                        WS_EX_NOPARENTNOTIFY,  // do not bother our parent window
                        className,
                        "sub",
                        WS_CHILD|WS_DISABLED,
                        x,y,width,height,
                        p_window,
                        NULL,
                        NULL,
                        NULL);

    auto user_data = new SubWindowUserData();
    user_data->repaint_callback = repaint_callback;
    user_data->repaint_callback_param = repaint_callback_param;

    SetWindowLongPtr(ret, GWLP_USERDATA, (LONG_PTR)user_data);
    if (!hideWindow)
        ShowWindow(ret, SW_SHOW);
    return ret;
}

void destroySubWindow(EGLNativeWindowType win){
    PostMessage(win, WM_CLOSE, 0, 0);
}

int moveSubWindow(FBNativeWindowType p_parent_window,
                  EGLNativeWindowType p_sub_window,
                  int x,
                  int y,
                  int width,
                  int height) {
    BOOL ret = MoveWindow(p_sub_window,
                          x,
                          y,
                          width,
                          height,
                          TRUE);
    return ret;
}