GlideDownloadImageUtil.java

package com.hotbitmapgg.moequest.utils;

import com.bumptech.glide.Glide;
import com.bumptech.glide.request.target.Target;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.concurrent.ExecutionException;
import rx.Observable;
import rx.Subscriber;
import rx.functions.Func1;
import rx.schedulers.Schedulers;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Environment;

/**
 * 使用Glide下载图片到本地工具类
 */
public class GlideDownloadImageUtil {

  public static Observable<Uri> saveImageToLocal(final Context context, final String url) {

    return Observable.create(new Observable.OnSubscribe<File>() {

      @Override
      public void call(Subscriber<? super File> subscriber) {

        File file;
        try {
          LogUtil.all("download" + url);
          file = Glide.with(context)
              .load(url)
              .downloadOnly(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)
              .get();

          subscriber.onNext(file);
        } catch (InterruptedException | ExecutionException e) {
          e.printStackTrace();
        }
      }
    }).flatMap(new Func1<File, Observable<Uri>>() {

      @Override
      public Observable<Uri> call(File file) {

        File mFile = null;
        try {

          String path = Environment.getExternalStorageDirectory() + File.separator +
              ConstantUtil.FILE_DIR;
          File dir = new File(path);
          if (!dir.exists()) {
            dir.mkdirs();
          }

          String fileName = System.currentTimeMillis() + ".jpg";

          mFile = new File(dir, fileName);
          FileInputStream fis = new FileInputStream(file.getAbsolutePath());

          int byteread;
          byte[] buf = new byte[1444];

          FileOutputStream fos = new FileOutputStream(mFile.getAbsolutePath());
          while ((byteread = fis.read(buf)) != -1) {
            fos.write(buf, 0, byteread);
          }

          fos.close();
          fis.close();
        } catch (Exception e) {
          e.printStackTrace();
          LogUtil.all("图片下载失败");
        }

        //更新本地图库
        Uri uri = Uri.fromFile(mFile);
        Intent mIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, uri);
        context.sendBroadcast(mIntent);

        return Observable.just(uri);
      }
    }).subscribeOn(Schedulers.io());
  }
}