Android - focus an input textfield inside a webview

Question

I have a problem to focus an input textfield inside a webview. In the webview a text input field is shown. If you click inside, the keyboard opens and the navigationbar is shown as required. The problem is, that the keyboard hides the input textfield. You can enter the text but you don´t see the input, until you scroll down. Is there a way to resize the webview so the input text field is shown or to automatically scroll to the textfield?
The immersive mode (for usability reasons - required) is used, so I can´t set the windwoSoftInputMode flag to adjustResize.