How to make a Scroll Listener for WebView in Android

Something like:

public class ObservableWebView extends WebView
{
    private OnScrollChangedCallback mOnScrollChangedCallback;

    public ObservableWebView(final Context context)
    {
        super(context);
    }

    public ObservableWebView(final Context context, final AttributeSet attrs)
    {
        super(context, attrs);
    }

    public ObservableWebView(final Context context, final AttributeSet attrs, final int defStyle)
    {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onScrollChanged(final int l, final int t, final int oldl, final int oldt)
    {
        super.onScrollChanged(l, t, oldl, oldt);
        if(mOnScrollChangedCallback != null) mOnScrollChangedCallback.onScroll(l, t, oldl, oldt);
    }

    public OnScrollChangedCallback getOnScrollChangedCallback()
    {
        return mOnScrollChangedCallback;
    }

    public void setOnScrollChangedCallback(final OnScrollChangedCallback onScrollChangedCallback)
    {
        mOnScrollChangedCallback = onScrollChangedCallback;
    }

    /**
     * Impliment in the activity/fragment/view that you want to listen to the webview
     */
    public static interface OnScrollChangedCallback
    {
        public void onScroll(int l, int t, int oldl, int oldt);
    }
}

Should work, this is untested but this works for almost every other view in Android.

You would implement like:

wv = (ObservableWebView) findViewById(R.id.scorllableWebview);
wv.setOnScrollChangedCallback(new OnScrollChangedCallback(){
    public void onScroll(int l, int t, int oldl, int oldt){
        if(t> oldt){
            //Do stuff
            System.out.println("Swipe UP");
            //Do stuff
        }
        else if(t< oldt){
            System.out.println("Swipe Down");
        }
        Log.d(TAG,"We Scrolled etc...");
    }
});

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