GestureListener for Webview to call a PopupWindow.

GestureListener.java

package com.example.myapplication;

import android.annotation.TargetApi;
import android.app.ActionBar;
import android.content.Context;
import android.graphics.drawable.BitmapDrawable;
import android.os.Build;
import android.util.Log;
import android.view.GestureDetector;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.webkit.WebView;
import android.widget.Button;
import android.widget.CalendarView;
import android.widget.ImageButton;
import android.widget.PopupMenu;
import android.widget.PopupWindow;
import android.widget.Toast;


public class GestureListener extends GestureDetector.SimpleOnGestureListener {

    public static final String TAG = "GestureListener";
    public static Context context;
    public View view;
    public PopupWindow popmenu;


    public GestureListener(Context context, View view) {
        super();
        this.view = view;
        this.context = context;

    }

    @Override
    public void onLongPress(MotionEvent e) {
        Log.i(TAG, "--Long Press" + getTouchType(e));

        // get click & adjust offsets
        int x_click = Math.round(e.getX()) - 100;
        int y_click = Math.round(e.getY()) + 280;

        //todo : change menu location as per click location

        LayoutInflater layoutInflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        final View customView = layoutInflater.inflate(R.layout.popup,null);

        ImageButton bookmark = (ImageButton) customView.findViewById(R.id.bookmark);
        ImageButton underline = (ImageButton) customView.findViewById(R.id.underline);
        ImageButton highlight = (ImageButton) customView.findViewById(R.id.highlight);

        popmenu = new PopupWindow(customView, 500, ActionBar.LayoutParams.WRAP_CONTENT);
        popmenu.showAtLocation(this.view, Gravity.NO_GRAVITY, x_click, y_click);


        bookmark.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Toast.makeText(context.getApplicationContext(),"Bookmark added",Toast.LENGTH_SHORT).show();

                popmenu.dismiss();
            }
        });
        underline.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                WebView xview = (WebView)view;
                xview.loadUrl("javascript:alert(showAndroidToast('underline'))");
                view = xview;

                popmenu.dismiss();
            }
        });
        highlight.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                WebView xview = (WebView)view;
                xview.loadUrl("javascript:alert(showAndroidToast('highlight'))");
                view = xview;

                popmenu.dismiss();
            }
        });

        popmenu.setOutsideTouchable(true);
        popmenu.setFocusable(true);
        // Show anchored to button
        popmenu.setBackgroundDrawable(new BitmapDrawable());


    }

    // BEGIN_INCLUDE(init_gestureListener)
    @Override
    public boolean onSingleTapUp(MotionEvent e) {
          Log.i(TAG, "--Single Tap Up" + getTouchType(e));
        return false;
    }

    @Override
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
        Log.i(TAG, "--Scroll" + getTouchType(e1));
        return false;
    }

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,float velocityY) {
        Log.i(TAG, "--Fling" + getTouchType(e1));
        return false;
    }

    @Override
    public void onShowPress(MotionEvent e) {
        // User performed a down event, and hasn't moved yet.
        Log.i(TAG, "--Show Press" + getTouchType(e));
    }

    @Override
    public boolean onDown(MotionEvent e) {
        // "Down" event - User touched the screen.
        Log.i(TAG, "--Down" + getTouchType(e));
        if(popmenu != null){
            popmenu.dismiss();
        }

        return false;
    }

    @Override
    public boolean onDoubleTap(MotionEvent e) {
        // User tapped the screen twice.
        Log.i(TAG, "--Double tap" + getTouchType(e));
        return false;
    }

    @Override
    public boolean onDoubleTapEvent(MotionEvent e) {
        // Since double-tap is actually several events which are considered one aggregate
        // gesture, there's a separate callback for an individual event within the doubletap
        // occurring.  This occurs for down, up, and move.
        Log.i(TAG, "--Event within double tap" + getTouchType(e));
        return false;
    }

    @Override
    public boolean onSingleTapConfirmed(MotionEvent e) {
        // A confirmed single-tap event has occurred.  Only called when the detector has
        // determined that the first tap stands alone, and is not part of a double tap.
        Log.i(TAG, "--Single tap confirmed" + getTouchType(e));
        return false;
    }
    // END_INCLUDE(init_gestureListener)


    /**
     * Returns a human-readable string describing the type of touch that triggered a MotionEvent.
     */

    private static String getTouchType(MotionEvent e){

        String touchTypeDescription = " ";
        int touchType = e.getToolType(0);

        switch (touchType) {
            case MotionEvent.TOOL_TYPE_FINGER:
                touchTypeDescription += "(finger)";
                break;
            case MotionEvent.TOOL_TYPE_STYLUS:
                touchTypeDescription += "(stylus, ";
                //Get some additional information about the stylus touch
                float stylusPressure = e.getPressure();
                touchTypeDescription += "pressure: " + stylusPressure;

                if(Build.VERSION.SDK_INT >= 21) {
                    touchTypeDescription += ", buttons pressed: " + getButtonsPressed(e);
                }

                touchTypeDescription += ")";
                break;
            case MotionEvent.TOOL_TYPE_ERASER:
                touchTypeDescription += "(eraser)";
                break;
            case MotionEvent.TOOL_TYPE_MOUSE:
                touchTypeDescription += "(mouse)";
                break;
            default:
                touchTypeDescription += "(unknown tool)";
                break;
        }

        return touchTypeDescription;
    }

    /**
     * Returns a human-readable string listing all the stylus buttons that were pressed when the
     * input MotionEvent occurred.
     */
    @TargetApi(21)
    private static String getButtonsPressed(MotionEvent e){
        String buttons = "";

        if(e.isButtonPressed(MotionEvent.BUTTON_PRIMARY)){
            buttons += " primary";
        }

        if(e.isButtonPressed(MotionEvent.BUTTON_SECONDARY)){
            buttons += " secondary";
        }

        if(e.isButtonPressed(MotionEvent.BUTTON_TERTIARY)){
            buttons += " tertiary";
        }

        if(e.isButtonPressed(MotionEvent.BUTTON_BACK)){
            buttons += " back";
        }

        if(e.isButtonPressed(MotionEvent.BUTTON_FORWARD)){
            buttons += " forward";
        }

        if (buttons.equals("")){
            buttons = "none";
        }

        return buttons;
    }

}