javascriptc++winapimicrosoft-edgewebview2

Win32 WebView2 Will Not Focus HTML Page


I am having a very difficult time trying to focus the HTML window that WebView2 loads on startup. I've tried JS focusing from within the web document, Callbacking back and forth between the C++ interface and the HTML page - nothing seems to work. The window will only be focused when some 'action' occurs like an alert dialog popping up. I was hoping to leverage the power of C++ and integrate it into the lightweight native browser client, but right now it is proving to be rather difficult. Would really appreciate some insight as to why this is occuring. I have shared 2 pieces of code, one is that of the WebView2 implementation, and the other one is a sample html file that focuses in normal situations. Please do not forget to HTML path to your custom one, I have marked it out for your convenience.

@echo off
cl /EHsc /GR /FI"iso646.h" /Zc:strictStrings /we4627 /we4927 /wd4351 /W4 /D"_CRT_SECURE_NO_WARNINGS" /nologo /D_UNICODE /DUNICODE /DWIN32 /D_WINDOWS /c /Ipath\to\webview2\include /Ipath\to\winrt\include webweb.cpp&^
link webweb.obj WebView2Loader.dll.lib /subsystem:windows user32.lib&^
webweb.exe
pause
#include <windows.h>
#include <stdlib.h>
#include <string>
#include <tchar.h>
#include <wrl.h>
#include <wil/com.h>
// include WebView2 header
#include "WebView2.h"

using namespace Microsoft::WRL;

// Global variables

// The main window class name.
static TCHAR szWindowClass[] = _T("DesktopApp");

// The string that appears in the application's title bar.
static TCHAR szTitle[] = _T("WebView sample");

HINSTANCE hInst;

// Forward declarations of functions included in this code module:
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

// Pointer to WebViewController
static wil::com_ptr<ICoreWebView2Controller> webviewController;

// Pointer to WebView window
static wil::com_ptr<ICoreWebView2> webviewWindow;

int CALLBACK WinMain(
    _In_ HINSTANCE hInstance,
    _In_ HINSTANCE hPrevInstance,
    _In_ LPSTR     lpCmdLine,
    _In_ int       nCmdShow
)
{
    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);
    wcex.style = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc = WndProc;
    wcex.cbClsExtra = 0;
    wcex.cbWndExtra = 0;
    wcex.hInstance = hInstance;
    wcex.hIcon = LoadIcon(hInstance, IDI_APPLICATION);
    wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wcex.lpszMenuName = NULL;
    wcex.lpszClassName = szWindowClass;
    wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION);

    if (!RegisterClassEx(&wcex))
    {
        MessageBox(NULL,
            _T("Call to RegisterClassEx failed!"),
            _T("Windows Desktop Guided Tour"),
            NULL);

        return 1;
    }

    // Store instance handle in our global variable
    hInst = hInstance;

    int dispw = GetSystemMetrics(SM_CXSCREEN);
    int disph = GetSystemMetrics(SM_CYSCREEN);
    int windw = dispw / 2;
    int windh = disph / 2;
    int x = (dispw - windw) / 2;
    int y = (disph - windh) / 2;

    // The parameters to CreateWindow explained:
    // szWindowClass: the name of the application
    // szTitle: the text that appears in the title bar
    // WS_OVERLAPPEDWINDOW: the type of window to create
    // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)
    // 500, 100: initial size (width, length)
    // NULL: the parent of this window
    // NULL: this application does not have a menu bar
    // hInstance: the first parameter from WinMain
    // NULL: not used in this application
    HWND hWnd = CreateWindow(
        szWindowClass,
        szTitle,
        WS_OVERLAPPEDWINDOW,
        x, y,
        windw, windh,
        NULL,
        NULL,
        hInstance,
        NULL
    );

    if (!hWnd)
    {
        MessageBox(NULL,
            _T("Call to CreateWindow failed!"),
            _T("Windows Desktop Guided Tour"),
            NULL);

        return 1;
    }

    // The parameters to ShowWindow explained:
    // hWnd: the value returned from CreateWindow
    // nCmdShow: the fourth parameter from WinMain
    ShowWindow(hWnd,
        nCmdShow);
    UpdateWindow(hWnd);

    // <-- WebView2 sample code starts here -->
    // Step 3 - Create a single WebView within the parent window
    // Locate the browser and set up the environment for WebView
    CreateCoreWebView2EnvironmentWithOptions(nullptr, nullptr, nullptr,
        Callback<ICoreWebView2CreateCoreWebView2EnvironmentCompletedHandler>(
            [hWnd](HRESULT result, ICoreWebView2Environment* env) -> HRESULT {

                // Create a CoreWebView2Controller and get the associated CoreWebView2 whose parent is the main window hWnd
                env->CreateCoreWebView2Controller(hWnd, Callback<ICoreWebView2CreateCoreWebView2ControllerCompletedHandler>(
                    [hWnd](HRESULT result, ICoreWebView2Controller* controller) -> HRESULT {
                        if (controller != nullptr) {
                            webviewController = controller;
                            webviewController->get_CoreWebView2(&webviewWindow);
                        }
                        // Add a few settings for the webview
                        // The demo step is redundant since the values are the default settings
                        ICoreWebView2Settings* Settings;
                        webviewWindow->get_Settings(&Settings);
                        Settings->put_IsScriptEnabled(TRUE);
                        Settings->put_AreDefaultScriptDialogsEnabled(FALSE);
                        Settings->put_IsWebMessageEnabled(FALSE);
                        RECT bounds;
                        GetClientRect(hWnd, &bounds);
                        webviewController->put_Bounds(bounds);
                        webviewWindow->AddScriptToExecuteOnDocumentCreated(L"text.setValue('ayee');", NULL);

                        
                        
webviewWindow->Navigate(L"file:///path/to/test.html");  



                        return S_OK;
                    }).Get());
                return S_OK;
            }).Get());
            


    
    // <-- WebView2 sample code ends here -->

    // Main message loop:
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return (int)msg.wParam;
}

//  FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_DESTROY  - post a quit message and return
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    TCHAR greeting[] = _T("Hello, Windows desktop!");

    switch (message)
    {
    case WM_SIZE:
        if (webviewController != nullptr) {
            RECT bounds;
            GetClientRect(hWnd, &bounds);
            webviewController->put_Bounds(bounds);
        };
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
        break;
    }

    return 0;
}
<!DOCTYPE HTML>
<HTML>
<HEAD>
<STYLE>
body
{
    display: flex;
    width: 100vw;
    overflow: none;
    scrollbar: none;
    align-items: center;
    justify-content: center;
}
#textarea
{
    width: 400px;
    height: 400px;
    resize: none;
    overflow:auto;
}
</STYLE>
<TITLE>EXAMPLE</TITLE>
</HEAD>
<BODY>
<textarea ID="textpane"></textarea>
<SCRIPT>
var te = document.getElementById('textpane');
window.onload = function()
{
    te.focus();
}
</SCRIPT>
</BODY>
</HTML>

Solution

  • After sifting through Microsoft documentation, figured that we have to add:

    webviewController->MoveFocus(COREWEBVIEW2_MOVE_FOCUS_REASON_PROGRAMMATIC);
    

    For the WebView component to focust in and of itself. Otherwise, some message/ JS alert dialog has to be rendered along with the view, which will be focused after we have exited out of the rendered dialog window.