TransitionsMapping.java

package architect;

import android.view.View;

import java.util.ArrayList;
import java.util.List;

/**
 * Views transitions mapping
 *
 * @author Lukasz Piliszczuk - lukasz.pili@gmail.com
 */
public class TransitionsMapping {

    final List<Mapping> list = new ArrayList<>();

    public TransitionsMapping byDefault(ViewTransition transition) {
        return new Mapping(null).withTransition(transition);
    }

    /**
     * Create new transition mapping to the destination view
     */
    public Mapping show(Class<? extends View> view) {
        return new Mapping(view);
    }

    public class Mapping {

        Class<? extends View> view;
        Class<? extends View>[] from;
        ViewTransition transition;

        private Mapping(Class<? extends View> view) {
            this.view = view;
        }

        /**
         * Specify specific originating views
         * If you want that to be any view, don't call this method
         */
        public Mapping from(Class<? extends View>... from) {
            Preconditions.checkArgument(from != null && from.length > 0, "From views cannot be null or empty");
            this.from = from;
            return this;
        }

        public TransitionsMapping withTransition(ViewTransition transition) {
            Preconditions.checkNotNull(transition, "Screen transition cannot be null");
            this.transition = transition;
            return build();
        }

        public TransitionsMapping withoutTransition() {
            return build();
        }

        private TransitionsMapping build() {
            list.add(this);
            return TransitionsMapping.this;
        }
    }
}