java - 如果声明不起作用？文字不变

Question

我编写的这段代码应该在每个整数 (0-4) 处显示不同的文本。 If 语句 0-3 很好，但是当整数变为 4 时，TextView 不会更改为“示例 5”。如果你按下按钮，什么也不会发生，我不知道为什么!需要帮助 ;)

package com.eastereggdevelopment.entwederoder;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

import java.util.Random;


public class Start extends AppCompatActivity {

private int question;
private TextView Question;
private TextView quNumber;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.start);

}

public void back(View view)
{
    if(question > 1)
    {
        question--;
        setQuestion();
    }

}

public void next(View view)
{
    if(question < 5)
    {
        question++;
        setQuestion();
    }

}

public void rumble(View view)
{
    Random rand = new Random();
    question = (rand.nextInt(4));
    setQuestion();
}

public void setQuestion()
{
    TextView Question = (TextView) findViewById(R.id.question);
    if(question == 0)
    {
        Question.setText("Example 1");
    }
    if(question == 1)
    {
        Question.setText("Example 2");
    }
    if(question == 2)
    {
        Question.setText("Example 3");
    }
    if(question == 3)
    {
        Question.setText("Example 4");
    }
    if(question == 4)
    {
        Question.setText("Example 5");
    }
}
}

谢谢你:)

Answer 1

这一行 - question = (rand.nextInt(4)); ，将值改为 5

The nextInt(int n) method is used to get a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.

Java Documentation