App crashes when loading the first page

package com.example.welse.interactivestory.ui;

import android.content.Intent;
import android.graphics.drawable.Drawable;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.welse.interactivestory.R;
import com.example.welse.interactivestory.Story;
import com.example.welse.interactivestory.model.page;

public class StoryActivity extends AppCompatActivity {


    public static final String TAG = StoryActivity.class.getSimpleName();


    private Story story;
    private ImageView storyImageView;
    private TextView textView;
    private Button choice1Button;
    private Button choice2Button;

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

        storyImageView = findViewById(R.id.storyImageView);
        textView = findViewById(R.id.textView);
        choice1Button = findViewById(R.id.choice1Button);
        choice2Button = findViewById(R.id.choice2Button);


        Intent intent = getIntent();
        String name =  intent.getStringExtra("name");
        if(name == null || name.isEmpty()){
            name = "friend";
        }
        Log.d(TAG, name );

        story = new Story();
        loadPage(0);


    }

    private void loadPage(int pageNumber) {
        page index = story.getPage(pageNumber);


        Drawable image = ContextCompat.getDrawable(this, index.getImageId());
        storyImageView.setImageDrawable(image);
    }


}

package com.example.welse.interactivestory;

import com.example.welse.interactivestory.model.choice;
import com.example.welse.interactivestory.model.page;


/**
 * Created by welse on 2018/2/17.
 */

public class Story {
    private page[] Pages;

    public Story(){
        Pages[0] = new page(R.drawable.page0, R.string.page0
                ,new choice(R.string.page0_choice1,1)
                ,new choice(R.string.page0_choice2,2));

        Pages[1] = new page(R.drawable.page1,
                R.string.page1,
                new choice(R.string.page1_choice1, 3),
                new choice(R.string.page1_choice2, 4));

        Pages[2] = new page(R.drawable.page2,
                R.string.page2,
                new choice(R.string.page2_choice1, 4),
                new choice(R.string.page2_choice2, 6));

        Pages[3] = new page(R.drawable.page3,
                R.string.page3,
                new choice(R.string.page3_choice1, 4),
                new choice(R.string.page3_choice2, 5));

        Pages[4] = new page(R.drawable.page4,
                R.string.page4,
                new choice(R.string.page4_choice1, 5),
                new choice(R.string.page4_choice2, 6));

        Pages[5] = new page(R.drawable.page5, R.string.page5);

        Pages[6] = new page(R.drawable.page6, R.string.page6);

    }


    public page getPage(int pageNumber) {
        if (pageNumber >= Pages.length){
            pageNumber = 0;
        }
        return Pages[pageNumber];
    }
}

package com.example.welse.interactivestory.model;

/**
 * Created by welse on 2018/2/15.
 */

public class page {
    private int imageId;
    private int textId;
    private choice choice1;
    private choice choice2;
    private boolean isFinalPage = false;


    public page(int imageId, int textId) {
        this.imageId = imageId;
        this.textId = textId;
        this.isFinalPage = true;

    }

    public page(int imageId, int textId, choice choice1, choice choice2) {
        this.imageId = imageId;
        this.textId = textId;
        this.choice1 = choice1;
        this.choice2 = choice2;
    }

    public boolean isFinalPage() {
        return isFinalPage;
    }

    public void setFinalPage(boolean finalPage) {
        isFinalPage = finalPage;
    }

    public int getImageId() {
        return imageId;
    }

    public void setImageId(int imageId) {
        this.imageId = imageId;
    }

    public int getTextId() {
        return textId;
    }

    public void setTextId(int textId) {
        this.textId = textId;
    }

    public choice getChoice1() {
        return choice1;
    }

    public void setChoice1(choice choice1) {
        this.choice1 = choice1;
    }

    public choice getChoice2() {
        return choice2;
    }

    public void setChoice2(choice choice2) {
        this.choice2 = choice2;
    }
}