import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.PictureDrawable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;

import com.bumptech.glide.Glide;
import com.larvalabs.svgandroid.SVG;
import com.larvalabs.svgandroid.SVGBuilder;

import java.io.IOException;
import java.util.ArrayList;

import uk.co.senab.photoview.PhotoView;


class ViewPagerAdapter extends PagerAdapter {

 private Context context;
 private ArrayList<String> images;
 private Canvas canvas = new Canvas();

 public ViewPagerAdapter(Context context, ArrayList<String> images) {
 this.context = context;
 this.images = images;
 }

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

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

 @Override
 public Object instantiateItem(ViewGroup container, int position) {
 View view = View.inflate(context, R.layout.view_pager_item, null);
 PhotoView photoView = (PhotoView) view.findViewById(R.id.photoview);
 //注意 一定要加這行代碼,不然會加載不出來
 photoView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
 //拿到圖片的url
 String url = images.get(position);
 //因為我要顯示所有圖片進行瀏覽 所以我用后綴名進行區分
 if (url.endsWith(".svg")) {

  try {
  //獲取assets目錄下的svg圖片的相對路徑
  String replaceUrl = url.replace("file:///android_asset/", "");
  SVG svg = new SVGBuilder().readFromAsset(context.getAssets(), replaceUrl).build();

  canvas.drawPicture(svg.getPicture());
  //github上的svg.createDrawable()沒有了,現在只有這個方法
  PictureDrawable drawable = svg.getDrawable();
  drawable.draw(canvas);
  photoView.setImageDrawable(drawable);

  } catch (IOException e) {
  e.printStackTrace();
  }
 } else {
  //用Glide加載圖片
  Glide.with(context).load(url).into(photoView);
 }
 container.addView(view, ViewPager.LayoutParams.MATCH_PARENT, ViewPager.LayoutParams.MATCH_PARENT);
 return view;
 }

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