Android popup error for TextView without focus

Activity.java

protected ErrorPopupHelper errorHelper = new ErrorPopupHelper();

mEditTextEmail.setOnFocusChangeListener(new View.OnFocusChangeListener() {
            @Override
            public void onFocusChange(View view, boolean hasFocus) {
                if (!hasFocus) {
                    if (!ValidatorUtil.isValidEmail(getEmail())) {
                      errorHelper.setError(mEditTextEmail, R.string.email_validation_error);
                    }
                }
            }
        });

ErrorPopup.java

/**
 * As TextView (and EditText as a subclass)
 * can show error if it is in focus only
 * (many thanks to person who added this if condition to Android source code) -
 * we have to create own popup window and style it with custom styles
 * (internal styles are unavailable for developers).
 * This is simple implementation of popup window.
 */
public class ErrorPopup extends PopupWindow {

    private final TextView mView;
    private boolean mAbove = false;

    public ErrorPopup(TextView v, int width, int height) {
        super(v, width, height);
        mView = v;
        mView.setBackgroundResource(R.color.text_gray); // TODO provide actual resource
    }

    public void fixDirection(boolean above) {
        mAbove = above;
        mView.setBackgroundResource(above ? R.color.text_gray : R.color.text_gray); // TODO provide actual resources
    }

    @Override
    public void update(int x, int y, int w, int h, boolean force) {
        super.update(x, y, w, h, force);

        boolean above = isAboveAnchor();
        if (above != mAbove) {
            fixDirection(above);
        }
    }
}

ErrorPopupHelper.java

/**
 * As TextView (and EditText as a subclass)
 * can show error if it is in focus only
 * (many thanks to person who added this if condition to Android source code) -
 * we have to create own popup window and style it with custom styles
 * (internal styles are unavailable for developers).
 * This is helper to show / hide popup errors and drawable icons for TextView.
 */
public class ErrorPopupHelper {

    private ErrorPopup mErrorPopup;
    private TextView lastTextView;

    /**
     * Hide error if user starts to write in this view
     */
    private TextWatcher textWatcher = new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
            if (mErrorPopup != null && mErrorPopup.isShowing()) {
                cancel();
            }
        }

        @Override
        public void afterTextChanged(Editable editable) {

        }
    };

    public void setError(TextView mTextView, int stringResId) {
        setError(mTextView, mTextView.getContext().getString(stringResId));
    }

    public void setError(TextView mTextView, CharSequence error) {
        cancel();

        CharSequence mError = TextUtils.stringOrSpannedString(error);
        if (mError != null) {
            showError(mTextView, error.toString());
        }
        mTextView.setCompoundDrawablesWithIntrinsicBounds(0, 0,
                mError == null ? 0 : android.R.drawable.stat_notify_error, 0);
        mTextView.addTextChangedListener(textWatcher);

        lastTextView = mTextView;
    }

    public void cancel() {
        if (lastTextView != null && lastTextView.getWindowToken() != null) {
            hideError();
            lastTextView.setCompoundDrawablesWithIntrinsicBounds(0, 0, 0, 0);
            lastTextView.removeTextChangedListener(textWatcher);
            lastTextView = null;
        }
    }

    private void showError(TextView mTextView, String error) {
        if (mTextView.getWindowToken() == null) {
            return;
        }

        if (mErrorPopup == null) {
            LayoutInflater inflater = LayoutInflater.from(mTextView.getContext());
            final TextView err = (TextView) inflater.inflate(R.layout.view_error_hint, null);

            final float scale = mTextView.getResources().getDisplayMetrics().density;
            mErrorPopup = new ErrorPopup(err, (int) (200 * scale + 0.5f), (int) (50 * scale + 0.5f));
            mErrorPopup.setFocusable(false);
            // The user is entering text, so the input method is needed.  We
            // don't want the popup to be displayed on top of it.
            mErrorPopup.setInputMethodMode(PopupWindow.INPUT_METHOD_NEEDED);
        }

        TextView tv = (TextView) mErrorPopup.getContentView();
        chooseSize(mErrorPopup, error, tv);
        tv.setText(error);

        mErrorPopup.showAsDropDown(mTextView, getErrorX(mTextView), 0);
        mErrorPopup.fixDirection(mErrorPopup.isAboveAnchor());
    }

    private void hideError() {
        if (mErrorPopup != null) {
            if (mErrorPopup.isShowing()) {
                mErrorPopup.dismiss();
            }
            mErrorPopup = null;
        }
    }

    private int getErrorX(TextView mTextView) {
        return mTextView.getWidth() - mErrorPopup.getWidth() - mTextView.getPaddingRight();
    }

    private void chooseSize(PopupWindow pop, CharSequence text, TextView tv) {
        int wid = tv.getPaddingLeft() + tv.getPaddingRight();
        int ht = tv.getPaddingTop() + tv.getPaddingBottom();

        int defaultWidthInPixels = tv.getResources().getDimensionPixelSize(
                R.dimen.textview_error_popup_default_width);
        Layout l = new StaticLayout(text, tv.getPaint(), defaultWidthInPixels,
                Layout.Alignment.ALIGN_NORMAL, 1, 0, true);
        float max = 0;
        for (int i = 0; i < l.getLineCount(); i++) {
            max = Math.max(max, l.getLineWidth(i));
        }

        /*
         * Now set the popup size to be big enough for the text plus the border capped
         * to DEFAULT_MAX_POPUP_WIDTH
         */
        pop.setWidth(wid + (int) Math.ceil(max));
        pop.setHeight(ht + l.getHeight());
    }
}