ImagesActivity.java

package com.daifan.activity;

import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.NetworkImageView;
import com.daifan.R;
import com.daifan.Singleton;

import java.util.Arrays;

public class ImagesActivity extends BaseActivity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_images);
        getSupportActionBar().setDisplayHomeAsUpEnabled(false);
        setTitle(R.string.image_viewer);

        ViewPager viewPager = (ViewPager) findViewById(R.id.view_images_viewpager);

        ImagePagerAdapter adapter = new ImagePagerAdapter(getDaifanApplication().getImageLoader());
        Intent in = getIntent();

        int currItem = 0;
        if (in != null) {
            String[] images = in.getStringArrayExtra("images");
            if (images != null)
                adapter.setImages(images);
            currItem = in.getIntExtra("currItem", 0);
            Log.d(Singleton.DAIFAN_TAG, "images:" + Arrays.toString(images));
        }

        viewPager.setAdapter(adapter);
        if (currItem > 0)
            viewPager.setCurrentItem(currItem);
    }

    private class ImagePagerAdapter extends PagerAdapter {

        private String[] images = new String[0];
        public ImageLoader mImageLoader;

        public ImagePagerAdapter(ImageLoader imageLoader) {
            mImageLoader=imageLoader;
        }

        @Override
        public int getCount() {
            return this.images.length;
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return view == ((ImageView) object);
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            Context context = ImagesActivity.this;
            NetworkImageView imageView = new NetworkImageView(context);
            int padding = context.getResources().getDimensionPixelSize(R.dimen.padding_medium);
            imageView.setPadding(padding, padding, padding, padding);
            imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
            imageView.setImageUrl(images[position], mImageLoader);
            ((ViewPager) container).addView(imageView, 0);
            return imageView;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            ((ViewPager) container).removeView((ImageView) object);
        }

        public void setImages(String[] images) {
            this.images = images;
        }

        public String[] getImages() {
            return images;
        }
    }
}