ResponseCommand.java

package com.kelin.mvvmlight.command;

import com.kelin.mvvmlight.command.ReplyCommand;

import rx.functions.Func0;
import rx.functions.Func1;

/**
 * Created by kelin on 15-8-4.
 */
public class ResponseCommand<T, R> {

    private Func0<R> execute0;
    private Func1<T, R> execute1;

    private Func0<Boolean> canExecute0;

    /**
     * like {@link ReplyCommand},but ResponseCommand can return result when command has executed!
     * @param execute function to execute when event occur.
     */
    public ResponseCommand(Func0<R> execute) {
        this.execute0 = execute;
    }


    public ResponseCommand(Func1<T, R> execute) {
        this.execute1 = execute;
    }


    public ResponseCommand(Func0<R> execute, Func0<Boolean> canExecute0) {
        this.execute0 = execute;
        this.canExecute0 = canExecute0;
    }


    public ResponseCommand(Func1<T, R> execute, Func0<Boolean> canExecute0) {
        this.execute1 = execute;
        this.canExecute0 = canExecute0;
    }


    public R execute() {
        if (execute0 != null && canExecute0()) {
            return execute0.call();
        }
        return null;
    }

    private boolean canExecute0() {
        if (canExecute0 == null) {
            return true;
        }
        return canExecute0.call();
    }


    public R execute(T parameter) {
        if (execute1 != null && canExecute0()) {
            return execute1.call(parameter);
        }
        return null;
    }

}