I have an interface, `Themable` which contains one method, `refereshTheme`

```
public interface Themable {
    void refreshTheme(ThemeUtil themeUtil);
}

```

and this interface is implemented by `ThemableTextView` which is a subclass of `AppCompatTextView` but when I check if the `ThemableTextView` is an instance of `Themable` it is returning false

```
private void setTheme(ViewGroup viewGroup, Themeutil themeUtil) {
        for (int i = 0; i < viewGroup.getChildCount(); i++) {
            if (viewGroup.getChildAt(i) instanceof ViewGroup)
                setTheme((ViewGroup) viewGroup.getChildAt(i), themeUtil);
            else if (viewGroup.getChildAt(i) instanceof Themable)
                ((Themable) viewGroup.getChildAt(i)).refreshTheme(themeUtil);
        }
    }

```

This is the xml layout

```
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingTop="@dimen/margin_20_dp">

    <Space
        android:id="@+id/centerSeparator"
        android:layout_width="@dimen/default_margin"
        android:layout_height="1dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"/>

    <android.support.v7.widget.CardView
        android:id="@+id/btnExtensions"
        android:layout_width="95dp"
        android:layout_height="95dp"
        android:layout_marginRight="@dimen/default_margin"
        android:layout_marginTop="@dimen/margin_20_dp"
        app:cardBackgroundColor="@color/cardview_light_background"
        app:cardCornerRadius="48dp"
        app:cardPreventCornerOverlap="true"
        app:layout_constraintRight_toLeftOf="@id/centerSeparator"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.v7.widget.AppCompatImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:clickable="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/ic_extension_admin"/>

    </android.support.v7.widget.CardView>

    <com.me.widget.ThemableTextView
        android:id="@+id/lblExtensions"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/extensions"
        android:textColor="@android:color/black"
        app:layout_constraintLeft_toLeftOf="@id/btnExtensions"
        app:layout_constraintRight_toRightOf="@id/btnExtensions"
        app:layout_constraintTop_toBottomOf="@id/btnExtensions"/>

    <android.support.v7.widget.CardView
        android:id="@+id/btnPhoneNumbers"
        android:layout_width="95dp"
        android:layout_height="95dp"
        android:layout_marginRight="@dimen/default_margin"
        android:layout_marginTop="@dimen/margin_20_dp"
        app:cardBackgroundColor="@color/cardview_light_background"
        app:cardCornerRadius="48dp"
        app:cardPreventCornerOverlap="true"
        app:layout_constraintRight_toLeftOf="@id/centerSeparator"
        app:layout_constraintTop_toBottomOf="@id/lblExtensions">

        <android.support.v7.widget.AppCompatImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:clickable="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/ic_phone_number_admin"/>

    </android.support.v7.widget.CardView>

    <com.me.widget.ThemableTextView
        android:id="@+id/lblPhoneNumber"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/phone_numbers"
        android:textColor="@android:color/black"
        app:layout_constraintLeft_toLeftOf="@id/btnPhoneNumbers"
        app:layout_constraintRight_toRightOf="@id/btnPhoneNumbers"
        app:layout_constraintTop_toBottomOf="@id/btnPhoneNumbers"/>

    <android.support.v7.widget.CardView
        android:id="@+id/btnGroups"
        android:layout_width="95dp"
        android:layout_height="95dp"
        android:layout_marginLeft="@dimen/default_margin"
        android:layout_marginTop="@dimen/margin_20_dp"
        app:cardBackgroundColor="@color/cardview_light_background"
        app:cardCornerRadius="48dp"
        app:cardPreventCornerOverlap="true"
        app:layout_constraintLeft_toRightOf="@id/centerSeparator"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.v7.widget.AppCompatImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:clickable="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/ic_groups_admin"/>

    </android.support.v7.widget.CardView>

    <com.me.widget.ThemableTextView
        android:id="@+id/lblGroups"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/groups"
        android:textColor="@android:color/black"
        app:layout_constraintLeft_toLeftOf="@id/btnGroups"
        app:layout_constraintRight_toRightOf="@id/btnGroups"
        app:layout_constraintTop_toBottomOf="@id/btnGroups"/>

    <android.support.v7.widget.CardView
        android:id="@+id/btnStatsAndGraphs"
        android:layout_width="95dp"
        android:layout_height="95dp"
        android:layout_marginLeft="@dimen/default_margin"
        android:layout_marginTop="@dimen/margin_20_dp"
        app:cardBackgroundColor="@color/cardview_light_background"
        app:cardCornerRadius="48dp"
        app:cardPreventCornerOverlap="true"
        app:layout_constraintLeft_toRightOf="@id/centerSeparator"
        app:layout_constraintTop_toBottomOf="@id/lblGroups">

        <android.support.v7.widget.AppCompatImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:clickable="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/ic_graphs_admin"/>

    </android.support.v7.widget.CardView>

    <com.me.widget.ThemableTextView
        android:id="@+id/lblGraphs"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/stats_graphs"
        android:textColor="@android:color/black"
        app:layout_constraintLeft_toLeftOf="@id/btnStatsAndGraphs"
        app:layout_constraintRight_toRightOf="@id/btnStatsAndGraphs"
        app:layout_constraintTop_toBottomOf="@id/btnStatsAndGraphs"/>

</android.support.constraint.ConstraintLayout>

```

Heres is the code for ThemableTextView

```
import android.content.Context;
import android.content.res.TypedArray;
import android.support.v4.content.ContextCompat;
import android.support.v7.widget.AppCompatTextView;
import android.util.AttributeSet;

import com.me.R;
import com.me.widget.utils.theme.themeUtil;
import com.me.widget.utils.theme.Themed;

public class ThemableTextView extends AppCompatTextView implements Themable {

    private boolean isInCard;

    public ThemableTextView(Context context) {
        this(context, null);
    }

    public ThemableTextView(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.textViewStyle);
    }

    public ThemableTextView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(attrs);
    }

    private void init(AttributeSet attrs) {
        TypedArray ta = getContext().obtainStyledAttributes(attrs, R.styleable.ThemedTextView);
        isInCard = ta.getBoolean(R.styleable.ThemableTextView_tv_is_in_card, false);
        ta.recycle();
    }

    @Override
    public void refreshTheme(ThemeUtil themeUtil) {
        if (isInCard) {
            themeUtil.setTextViewColor(this, ContextCompat.getColor(getContext(), R.color.md_grey_800));
            return;
        }
        themeUtil.setTextViewColor(this, themeUtil.getTextColor());
    }

}

```

this line

```
if (viewGroup.getChildAt(i) instanceof Themable)

```

is returning false even for `ThemableTextView`. Does anyone know why it is returning false