从 URL 下载图像并将其保存到内部存储器的最佳方法

Question

I am developing an app in which I want to download image from URL. I need to download these images at once and stored it into internal storage. There are more than 200 images for downloading. Please tell me the best way to download these images at minimum time possible. If any third part library is available the please tell.

Answer 1

Consider using Picasso for your purpose. I'm using it in one of my project. To save image on external disk you can use following:

 Picasso.with(mContext)
        .load(ImageUrl)
        .into(new Target() {
            @Override
            public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
                try {
                    String root = Environment.getExternalStorageDirectory().toString();
                    File myDir = new File(root + "/yourDirectory");

                    if (!myDir.exists()) {
                        myDir.mkdirs();
                    }

                    String name = new Date().toString() + ".jpg";
                    myDir = new File(myDir, name);
                    FileOutputStream out = new FileOutputStream(myDir);
                    bitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);

                    out.flush();
                    out.close();                        
                } catch(Exception e){
                    // some action
                }
            }

            @Override
            public void onBitmapFailed(Drawable errorDrawable) {
            }

            @Override
            public void onPrepareLoad(Drawable placeHolderDrawable) {
            }
        }
    );

From here you can download this library.

Answer 2

You can download th image from an url like this:

URL url = new URL("http://www.yahoo.com/image_to_read.jpg");
InputStream in = new BufferedInputStream(url.openStream());
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] buf = new byte[1024];
int n = 0;
while (-1!=(n=in.read(buf)))
{
   out.write(buf, 0, n);
}
out.close();
in.close();
byte[] response = out.toByteArray();

And you may then want to save the image so do:

FileOutputStream fos = new FileOutputStream("C://borrowed_image.jpg");
fos.write(response);
fos.close();

Answer 3

Ok first of all implement that library into gradle of app level for load the image from url into image view:

 implementation("com.github.bumptech.glide:glide:4.6.1")
            {
                exclude group: "com.android.support"
            }

Now write below code in your activity for load the image::

Glide.with(this).load("url of your image").thumbnail(Glide.with(this).load(R.drawable.loadingsingleimage)).into(imageView);

Now download it into the your device storage by implementing the following code..

 download.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                try {
                    BitmapDrawable drawable = (BitmapDrawable) imageView.getDrawable();
                    Bitmap bitmap = drawable.getBitmap();

                    File filepath = Environment.getExternalStorageDirectory();
                    File dir = new File(filepath.getAbsolutePath() + "/MotivationalQuotes/");
                    dir.mkdir();

                    File file = new File(dir, System.currentTimeMillis() + ".png");
                    try {
                        outputStream = new FileOutputStream(file);
                    } catch (FileNotFoundException e) {
                        Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();

                    }

                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);

                    try {
                        outputStream.flush();
                    } catch (IOException e) {
                        Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                    try {
                        outputStream.close();
                    } catch (IOException e) {
                        Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                    Toast.makeText(getApplicationContext(), "Downloaded into MotivationalQuotes.", Toast.LENGTH_SHORT).show();
                }
                catch (Exception e) {
                    Toast.makeText(getApplicationContext(), "Image is not loaded yet...", Toast.LENGTH_SHORT).show();
                }
            }

        });

Answer 4

BitmapDrawable bitmapDrawable = (BitmapDrawable) holder.post_image.getDrawable();
                        Bitmap bitmap = bitmapDrawable.getBitmap();
                        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
                        bitmap.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
                        MediaStore.Images.Media.insertImage(mContext.getContentResolver(), bitmap, "IMG_" + Calendar.getInstance().getTime(), null);

It is quite a simple job...

Answer 5

 const actionDownloadImage = (urls) => {
        urls.map((url) => {
            const splitUrl = url.split("/");
            const filename = splitUrl[splitUrl.length - 1];
            fetch(url)
                .then((response) => {
                    response.arrayBuffer().then(function (buffer) {
                        const url = window.URL.createObjectURL(new Blob([buffer]));
                        const link = document.createElement("a");
                        link.href = url;
                        link.setAttribute("download", filename); //or any other extension
                        document.body.appendChild(link);
                        link.click();
                        document.body.removeChild(link);
                    });
                })
                .catch((err) => {
                    console.log(err);
                });
        });
    }