onLoadStart property

Implementation

@SupportedPlatforms(
  platforms: [
    AndroidPlatform(
      apiName: 'WebViewClient.onPageStarted',
      apiUrl:
          'https://developer.android.com/reference/android/webkit/WebViewClient#onPageStarted(android.webkit.WebView,%20java.lang.String,%20android.graphics.Bitmap)',
    ),
    IOSPlatform(
      apiName: 'WKNavigationDelegate.webView',
      apiUrl:
          'https://developer.apple.com/documentation/webkit/wknavigationdelegate/1455621-webview',
    ),
    MacOSPlatform(
      apiName: 'WKNavigationDelegate.webView',
      apiUrl:
          'https://developer.apple.com/documentation/webkit/wknavigationdelegate/1455621-webview',
    ),
    WebPlatform(
      note:
          "It will be dispatched at the same time of [onLoadStop] event because there isn't any way to capture the real load start event from an iframe. If the current iframe location isn't accessible because of the browser's same-origin policy, the [url] parameter will be null.",
    ),
    WindowsPlatform(
      apiName: 'ICoreWebView2.add_NavigationStarting',
      apiUrl:
          'https://learn.microsoft.com/en-us/microsoft-edge/webview2/reference/win32/iwebview2webview?view=webview2-0.8.355#add_navigationstarting',
    ),
    LinuxPlatform(
      apiName: 'WebKitWebView::load-changed',
      apiUrl:
          'https://wpewebkit.org/reference/stable/wpe-webkit-2.0/signal.WebView.load-changed.html',
      note: 'Fired when WebKitLoadEvent is WEBKIT_LOAD_STARTED.',
    ),
  ],
)
final void Function(T controller, WebUri? url)? onLoadStart;