Asynctask下载并将Jpg设置为imageView

Question

在互联网的帮助下，我可以下载jpg并将其设置为带位图的ImageView。但是，我想将其保留为点动或png。

我该怎么做？

  public class GetFlickr  extends AsyncTask<String, String, Bitmap> {

    private ProgressBar pBar;
    private String file = "flickr.xml";
    private WeakReference<ImageView> imageViewWeakReference;

  GetFlickr(ImageView Iv){
     imageViewWeakReference = new WeakReference<>(Iv);
  }

    @Override
    protected void onPreExecute(){
      super.onPreExecute();
      pBar = findViewById(R.id.progressBar);
      pBar.setProgress(0);
      pBar.setVisibility(View.VISIBLE);
    }

    @Override
    protected Bitmap doInBackground(String... strings) {
      Bitmap bitmap=null;

      try{

        URL urlfinal = new URL("https://farm66.staticflickr.com/65535/49344706212_80c4e61053.jpg");
        HttpURLConnection connection1 = (HttpURLConnection) urlfinal.openConnection();
        connection1.connect();
        //FileOutputStream fOut2= openFileOutput("flickr.jpg", MODE_PRIVATE);
        InputStream fOut2 = urlfinal.openStream();
        bitmap = BitmapFactory.decodeStream(fOut2);

      } catch (MalformedURLException e){
        e.printStackTrace();
      } catch (IOException e){
        e.printStackTrace();
      }
      return bitmap;
    }

    protected void onProgressUpdate(String... progress) {
      pBar.setProgress(Integer.parseInt(progress[0]));
    }

    @Override
    protected void onPostExecute(Bitmap bitmap) {
      ImageView Iv = imageViewWeakReference.get();
      if (Iv != null){
        Iv.setImageBitmap(bitmap);
      }
      pBar.setVisibility(View.GONE);
    }
  }
}

Answer 1

一个好的帮助将是库Picasso

您可以轻松处理在线图像，自动缓存等。>

只需插入您的gradle：

implementation 'com.squareup.picasso:picasso:(insert latest version)'

Answer 2

我建议您使用Glide库。它支持LruCache和diskCache。

dependencies {
  implementation 'com.github.bumptech.glide:glide:4.10.0'
  annotationProcessor 'com.github.bumptech.glide:compiler:4.10.0'
}

然后按以下方式加载：