AttrsDelegate that can simply retrieve attrs for your custom widget

AttrsDelegate.java

/**
 * Helper in work with custom attributes on some widget
 * <p>
 * Just pass to this attributeSet from your widget constructor and {@link StyleableRes}
 *
 * @author Anton Vlasov - whalemare
 * @since 2017
 */
public class AttrsDelegate {

    private final TypedArray typedArray;

    /**
     * @param context      for obtain styled attrs
     * @param attributeSet set from your constructor.
     *                     If you pass <b>null</b>, function {@link #apply(Invokable)} not be called!
     * @param attrs        your custom {@link StyleableRes}
     */
    public AttrsDelegate(Context context,
                         @Nullable AttributeSet attributeSet,
                         @StyleableRes int[] attrs) {
        if (attributeSet == null) {
            typedArray = null;
        } else {
            typedArray = context.obtainStyledAttributes(attributeSet, attrs);
        }
    }

    /**
     * You can call this function only once.
     * After that resources will be recycled
     *
     * @param action your function for apply some widget attrs
     * @see TypedArray#recycle()
     */
    public void apply(@NonNull Invokable<TypedArray> action) {
        if (typedArray == null) return;

        action.invoke(typedArray);
        typedArray.recycle();
    }

    interface Invokable<T> {
        void invoke(T t);
    }
}

CustomView.java

public class CustomView extends LinearLayout {

    // call this method in your constructor
    protected void setup(Context context, @Nullable AttributeSet attrs) {
        AttrsDelegate attrsDelegate = new AttrsDelegate(context, attrs, R.styleable.TakePhotoWidget);
        attrsDelegate.apply(widgetAttrs -> {
            title = widgetAttrs.getString(R.styleable.TakePhotoWidget_title);
            setTitle(title);
            setMaxPhotosCount(widgetAttrs.getInteger(R.styleable.TakePhotoWidget_maxPhotosCount, 1));
            setCounterEnabled(widgetAttrs.getBoolean(R.styleable.TakePhotoWidget_counterEnabled, false));
            setEnabledImageViewer(widgetAttrs.getBoolean(R.styleable.TakePhotoWidget_imageViewerEnabled, true));
        });

        handleCounter(getPhotosCount(), getMaxPhotosCount());
    }
}