小白问个问题，空指针，Android，Viewpager

Question

package com.example.viewpage_animation_app;

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

import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity {

ViewPager iviewpager;
List<ImageView> ilist = new ArrayList<ImageView>();
int[] image = new int[] { R.drawable.ic_launcher, R.drawable.guide_image2, R.drawable.guide_image3 };

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    init();
    iviewpager.setAdapter(new PagerAdapter() {

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            // TODO Auto-generated method stub
            if (ilist.get(position) != null) {
                container.addView(ilist.get(position));

            } else {
                Toast.makeText(MainActivity.this, "The null", Toast.LENGTH_SHORT).show();
            }

            return ilist.get(position);

        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            // TODO Auto-generated method stub
            container.removeView((View) object);
        }

        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            // TODO Auto-generated method stub
            return arg0 == arg1;
        }

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return ilist.size();
        }
    });

}

private void init() {
    // TODO Auto-generated method stub
    iviewpager = (ViewPager) findViewById(R.id.viewpager);
    for (int i = 0; i < image.length; i++) {
        ImageView imageView = (ImageView) findViewById(image[i]);
        ilist.add(imageView);

    }

}

}

container.addView(ilist.get(position)); 此句一直显示空指针，加了一个条件语句，虽然不报错了，输出的是下面的那个toast。。。。。

Answer 1

、、
iviewpager = (ViewPager) findViewById(R.id.viewpager);
for (int i = 0; i < image.length; i++) {
ImageView imageView = (ImageView) findViewById(image[i]);
ilist.add(imageView);
}
、、
这里你就别findViewById了，用new ImageView创建吧。findViewById(image[i]);你获取的是什么，这个方法你都用错了