Getting android specific attribute in custom component

I have my own custom component in xml written like this

    <com.app.components.CustomComponent
        android:id="@+id/component"
        android:layout_width="96dp"
        android:layout_height="96dp"
        android:scaleType="fitCenter"/>

Attrs:

<declare-styleable name="CustomComponent">
    <attr name="android:scaleType"/>
</declare-styleable>

My custom component constructor looks like this

@Bind(R.id.imageView) ImageView imageView;
@Bind(R.id.progressBar) ProgressBar progressBar;

public CustomComponent(Context context, AttributeSet attrs) {
    super(context, attrs);

    TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.FunGuideImageView, 0, 0);

  // how to correctly get scale type defined in xml ?
    int scaleType = a.getValue(R.styleable.CustomComponent_android_scaleType,
            ImageView.ScaleType);


    LayoutInflater inflater = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View view = inflater.inflate(R.layout.imageview, this, true);
    ButterKnife.bind(view);
    imageView.setScaleType( scaleType );

}

How can I get the scaleType defined in xml and set it to my imageView?