How to override web view text selection menu in android

You need to overwrite action menus of activity

more info you can read :https://developer.android.com/guide/topics/ui/menus.html

HOW TO OVERWRITE:

@Override
public void onActionModeStarted(android.view.ActionMode mode) {
    mode.getMenu().clear();
    Menu menus = mode.getMenu();
    mode.getMenuInflater().inflate(R.menu.highlight,menus);
    super.onActionModeStarted(mode);
}

highlight

    <?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/impclick"
        android:title="Mark As Important"
      />
    <item android:id="@+id/colorclick"
        android:title="Mark with color" />
</menu>

This solution is not depend on Action mode of Activity and work for all android platform

I tried to give answer but it exceeds the character limits so I am putting some code part

Reference Link 1 For Selection On Web View

https://github.com/btate/BTAndroidWebViewSelection

Reference Link 2 For Making Web View Marker

https://github.com/liufsd/WebViewMarker

Both above links really plays important role and developed by some awesome developers. First Of All Need Some Research On TextSelectionSupport Class From Reference Link 1. I customised two lines of code in TextSelectionSupport class to get rectangle of selection in Selection Listener here.

Clone the Sample Project from here https://github.com/ab-cse-2014/WebViewSelection.git

See The implementation of CustomWebView and Use Of TextSelectionSupport class.

This is my web view class in project

 import android.content.Context;
 import android.graphics.Rect;
 import android.os.Build;
 import android.support.annotation.RequiresApi;
 import android.support.v7.app.AppCompatActivity;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.Gravity;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.webkit.WebView;
 import android.widget.PopupWindow;
 import android.widget.Toast;

 import com.cse.webviewtextselection.R;
 import com.cse.webviewtextselection.webviewmaker.TextSelectionSupport;

 public class CustomWebView extends WebView {

private final String TAG = this.getClass().getSimpleName();

private Context mContext;

private TextSelectionSupport mTextSelectionSupport;

private PopupWindow mPopupWindow;

private int currentTop;

public CustomWebView(Context context) {
    super(context);
    mContext = context;
    initSetUp();
    preparePopupWindow();
}

public CustomWebView(Context context, AttributeSet attrs) {
    super(context, attrs);
    mContext = context;
    initSetUp();
    preparePopupWindow();
}

public CustomWebView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    mContext = context;
    initSetUp();
    preparePopupWindow();
}

@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
public CustomWebView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
    super(context, attrs, defStyleAttr, defStyleRes);
    mContext = context;
    initSetUp();
    preparePopupWindow();
}

private void initSetUp() {

    mTextSelectionSupport = TextSelectionSupport.support((AppCompatActivity) mContext, this);
    mTextSelectionSupport.setSelectionListener(new TextSelectionSupport.SelectionListener() {
        @Override
        public void startSelection() {

        }

        @Override
        public void selectionChanged(String text, Rect rect) {
            Toast.makeText(mContext, text, Toast.LENGTH_SHORT).show();
            showPopAtLocation(mPopupWindow, rect.left, rect.top);
        }

        @Override
        public void endSelection() {
            if (mPopupWindow != null) {
                mPopupWindow.dismiss();
            }
        }
    });
}

private void preparePopupWindow() {

    LayoutInflater layoutInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View customPopupView =  layoutInflater.inflate(R.layout.custom_popup_layout, null);
    mPopupWindow = new PopupWindow(customPopupView, LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, true);
    mPopupWindow.setAnimationStyle(android.R.style.Animation_Dialog);

}

private void showPopAtLocation(PopupWindow mPopupWindow, int x, int y) {

    if (mPopupWindow != null) {

        if (currentTop != 0 || currentTop > ((AppCompatActivity)mContext).getWindow().getDecorView().getHeight()) {

                if (y > currentTop) {

                    y -= currentTop;

                }

        }

        Log.d("Current Top : ", String.valueOf(currentTop));
        Log.d("Y : ", String.valueOf(y));

        //mPopupWindow.showAtLocation(((AppCompatActivity)mContext).findViewById(R.id.parentRelativeLayout), Gravity.NO_GRAVITY, x, y);
        mPopupWindow.showAtLocation(((AppCompatActivity)mContext).getWindow().getDecorView(), Gravity.NO_GRAVITY, x, y);


    }

}

@Override
protected void onScrollChanged(int newLeft, int newTop, int oldLeft, int oldTop) {

    currentTop = newTop;


    super.onScrollChanged(newLeft, newTop, oldLeft, oldTop);
}
 }

Custom Popup Menu XML like androids smart text selection(custom_popup_layout.xml)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/myCustomMenuLinearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:background="@android:color/transparent">

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:background="@android:color/white"
    android:elevation="5dp"
    android:layout_margin="12dp">

    <TextView
        android:id="@+id/menuOne"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Mark With Color"
        android:textColor="@android:color/black"
        android:padding="10dp"
        android:maxLines="1"/>

    <TextView
        android:id="@+id/menuTwo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Mark As Important"
        android:textColor="@android:color/black"
        android:padding="10dp"
        android:maxLines="1"/>

    <TextView
        android:id="@+id/menuThree"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show More"
        android:textColor="@android:color/black"
        android:padding="10dp"
        android:maxLines="1"/>

</LinearLayout>



</LinearLayout>

Output Screen Shots

what you need is action mode, in activity:

    @Override
    public void onActionModeStarted(ActionMode mode) {
        Menu menu = mode.getMenu();

        // you can remove original menu: copy, cut, select all, share ... or not
        menu.clear();

        // here i will get text selection by user
        menu.add(R.string.action_menu_preview_card)
                .setEnabled(true)
                .setVisible(true)
                .setOnMenuItemClickListener(item -> {
                    if (mWebview != null) {
                        mWebview.evaluateJavascript("window.getSelection().toString()", value -> {
                            value = StringUtil.trimToNull(value);
                            if (value != null) {
                                // do something about user select
                            }
                        });
                    }
                    // Post a delayed runnable to avoid a race condition
                    // between evaluateScript() result and mode.finish()
                    new Handler().postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            mode.finish();
                        }
                    }, 200);
                    return true;
                });
        super.onActionModeStarted(mode);
    }

i has test it above android 21, this can handle action mode menu click, and mode.getMenuInflater().inflate(...) can't do it.