SoftInputAssist.java

public class SoftInputAssist {
    private View rootView;
    private ViewGroup contentContainer;
    private ViewTreeObserver viewTreeObserver;
    private ViewTreeObserver.OnGlobalLayoutListener listener = () -> possiblyResizeChildOfContent();
    private Rect contentAreaOfWindowBounds = new Rect();
    private FrameLayout.LayoutParams rootViewLayout;
    private int usableHeightPrevious = 0;

    public SoftInputAssist(Activity activity) {
        contentContainer = (ViewGroup) activity.findViewById(android.R.id.content);
        rootView = contentContainer.getChildAt(0);
        rootViewLayout = (FrameLayout.LayoutParams) rootView.getLayoutParams();
    }

    public void onPause() {
        if (viewTreeObserver.isAlive()) {
            viewTreeObserver.removeOnGlobalLayoutListener(listener);
        }
    }

    public void onResume() {
        if (viewTreeObserver == null || !viewTreeObserver.isAlive()) {
            viewTreeObserver = rootView.getViewTreeObserver();
        }

        viewTreeObserver.addOnGlobalLayoutListener(listener);
    }

    public void onDestroy() {
        rootView = null;
        contentContainer = null;
        viewTreeObserver = null;
    }

    private void possiblyResizeChildOfContent() {
        contentContainer.getWindowVisibleDisplayFrame(contentAreaOfWindowBounds);
        int usableHeightNow = contentAreaOfWindowBounds.height();

        if (usableHeightNow != usableHeightPrevious) {
            rootViewLayout.height = usableHeightNow;
            rootView.layout(contentAreaOfWindowBounds.left, contentAreaOfWindowBounds.top, contentAreaOfWindowBounds.right, contentAreaOfWindowBounds.bottom);
            rootView.requestLayout();

            usableHeightPrevious = usableHeightNow;
        }
    }
}

I am able to implement this and the status bar is not flickering anymore, need to let it run in Handler when calling "possiblyResizeChildOfContent". Not sure whether this works on anyone else, but give it a try. The code below is in Kotlin.

class SoftInputAssist(activity: Activity) {
    private var contentContainer: ViewGroup?
    private var rootView: View?
    private val rootViewLayout: FrameLayout.LayoutParams?

    private val contentAreaOfWindowBounds: Rect = Rect()
    private var viewTreeObserver: ViewTreeObserver? = null
    private var usableHeightPrevious = 0

    private val listener = OnGlobalLayoutListener {
        possiblyResizeChildOfContent()
    }

    init {
        contentContainer = activity.contentRootView as? ViewGroup
        rootView = contentContainer?.getChildAt(0)
        rootViewLayout = rootView?.layoutParams as? FrameLayout.LayoutParams
    }

    fun onPause() {
        if (viewTreeObserver != null && viewTreeObserver!!.isAlive) {
            viewTreeObserver?.removeOnGlobalLayoutListener(listener)
        }
    }

    fun onResume() {
        viewTreeObserver = rootView?.viewTreeObserver

        if (viewTreeObserver != null) {
            viewTreeObserver?.addOnGlobalLayoutListener(listener)
        }
    }

    fun onDestroy() {
        contentContainer = null
        rootView = null
        viewTreeObserver = null
    }

    private fun possiblyResizeChildOfContent() {
        runOnMainThread {
            contentContainer?.getWindowVisibleDisplayFrame(contentAreaOfWindowBounds)
            val usableHeightNow: Int = contentAreaOfWindowBounds.bottom

            if (usableHeightNow != usableHeightPrevious) {
                rootViewLayout?.height = usableHeightNow

                rootView?.layout(
                    contentAreaOfWindowBounds.left - (contentContainer?.x?.toInt() ?: 0),
                    contentAreaOfWindowBounds.top - (contentContainer?.y?.toInt() ?: 0),
                    contentAreaOfWindowBounds.right - (contentContainer?.x?.toInt() ?: 0),
                    contentAreaOfWindowBounds.bottom - (contentContainer?.y?.toInt() ?: 0)
                )

                rootView?.requestLayout()
                usableHeightPrevious = usableHeightNow
            }
        }
    }
}

val Activity.contentRootView: View?
    get() = window?.decorView?.findViewById(android.R.id.content) ?: findViewById(android.R.id.content)

private object ContextHandler {
    val handler = Handler(Looper.getMainLooper())
}

fun runOnMainThread(action: () -> Unit) {
    ContextHandler.handler.post {
        action()
    }
}

For me this solution worked perfectly with windowSoftInputMode= adjustPan and then adjusting my NestedScrollView's parent's top, start, end, and bottom constraints with the parent with 0dp height

thanks.

Worked for me after I have replaced

int usableHeightNow = contentAreaOfWindowBounds.height();

with

int usableHeightNow = contentAreaOfWindowBounds.bottom;

otherwise I had a large gap at the bottom of the screen.

Thanks Bro it was a problem for me. But a little bit problem while launching the activity, splash like problem. If you found an answer please email me. twodiesdeveloper@gmail.com. I'll be waiting to your answer.

Can this be used in fragment...