Android WebView File Download

android-webview-download.java

mWebContents.setDownloadListener(new DownloadListener() {

  @Override
  public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimeType, long contentLength) {

    try {
      DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));
      request.setMimeType(mimeType);
      request.addRequestHeader("User-Agent", userAgent);
      request.setDescription("Downloading file");
      String fileName = contentDisposition.replace("inline; filename=", "");
      fileName = fileName.replaceAll(".+UTF-8''", "");
      fileName = fileName.replaceAll("\"", "");
      fileName = URLDecoder.decode(fileName, "UTF-8");
      request.setTitle(fileName);
      request.allowScanningByMediaScanner();
      request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
      request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, fileName);
      DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
      dm.enqueue(request);
      Toast.makeText(getApplicationContext(), "Downloading File", Toast.LENGTH_LONG).show();
    } catch (Exception e) {

      if (ContextCompat.checkSelfPermission(MainActivity.this,
              android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
              != PackageManager.PERMISSION_GRANTED) {
        // Should we show an explanation?
        if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
                android.Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
          Toast.makeText(getBaseContext(), "첨부파일 다운로드를 위해\n동의가 필요합니다.", Toast.LENGTH_LONG).show();
          ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE},
                  110);
        } else {
          Toast.makeText(getBaseContext(), "첨부파일 다운로드를 위해\n동의가 필요합니다.", Toast.LENGTH_LONG).show();
          ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE},
                  110);
        }
      }
    }
  }