Question

我正在使用此代码将图像保存到文件夹中。

File file = new File(Environment.getExternalStorageDirectory() + "/MyAppFolder/" + getFilenameFromURL(imageUrl));
            if(!file.exists()) file.mkdirs();

但是还创建了一个额外的文件夹，其名称与图像名称相同......

Answer 1

试试这个：

File RootFile;
File root = Environment.getExternalStorageDirectory();
File dir = new File(root.getAbsolutePath() + "/MyAppFolder/");
String title=" <your title>";

if (!dir.exists()) {
     dir.mkdirs();
}
RootFile = new File(dir, title);

Answer 2

You must declare permissions in AndoridManifest.xml

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />              
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> 

//Call this method on image loading   in your yourActivity.java
                    if (NetConnectivity.isOnline(getApplicationContext())) {

                  //define String link,filename varialble as global variables in activity    
                    link = "Replace Remote URL";
                   filename = "Replace your new name of image";

//Here you can check folder is exist or not, if not exist then folder has been created
                        String extStorageDirectory = Environment.getExternalStorageDirectory()
                                .toString();
                        File folder = new File(extStorageDirectory, "YourFolderName");
                        folder.mkdir();

                        Log.d("File New Name : ", System.currentTimeMillis() + filename);
                        Log.d("Folder PAth : ", folder.toString());
                        File file = new File(folder, System.currentTimeMillis() + filename);
                        try {
                            file.createNewFile();
                        } catch (IOException e1) {
                            e1.printStackTrace();
                        }

                        //DownloadFile("http://www.nmu.ac.in/ejournals/aspx/courselist.pdf", file);


                        new DownloadFileFromURL().execute(link);
                    } else {
                        Toast.makeText(getApplicationContext(), getString(R.string.no_network2), Toast.LENGTH_SHORT).show();
                    }

//DownloadFileFromURL Async Task  ,Copy this method outside OnCreate() Method
class DownloadFileFromURL extends AsyncTask<String, String, String> {

    private ProgressDialog pDialogkk;

    /**
     * Before starting background thread Show Progress Bar Dialog
     */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        pDialogkk = new ProgressDialog(FilesInDownloadsActivity.this);
        pDialogkk.setMessage("Downloading file. Please wait...");
        pDialogkk.setIndeterminate(false);
        pDialogkk.setMax(100);
        pDialogkk.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        pDialogkk.setCancelable(true);
        pDialogkk.show();

    }

    @Override
    protected String doInBackground(String... f_url) {
        int count;

        try {
            URL url = new URL(f_url[0]);
            if (url.equals("") || url.equals(null)) {
                Toast.makeText(getApplicationContext(), "Not Found",
                        Toast.LENGTH_SHORT).show();
            } else {

                URLConnection conection = url.openConnection();
                conection.connect();
                // getting file length
                int lenghtOfFile = conection.getContentLength();

                // input stream to read file - with 8k buffer
                InputStream input = new BufferedInputStream(
                        url.openStream(), 8192);

                // Output stream to write file
                OutputStream output = new FileOutputStream("/sdcard/" + getString(R.string.app_name) + "/"
                        + filename);

                byte data[] = new byte[1024];

                long total = 0;

                while ((count = input.read(data)) != -1) {
                    total += count;
                    // publishing the progress....
                    // After this onProgressUpdate will be called
                    publishProgress(""
                            + (int) ((total * 100) / lenghtOfFile));

                    // writing data to file
                    output.write(data, 0, count);
                }

                // flushing output
                output.flush();

                // closing streams
                output.close();
                input.close();
            }

        } catch (Exception e) {
            Log.e("Error: ", e.getMessage());
        }

        return null;
    }

    /**
     * Updating progress bar
     */
    protected void onProgressUpdate(String... progress) {
        // setting progress percentage
        pDialogkk.setProgress(Integer.parseInt(progress[0]));
    }

    /**
     * After completing background task Dismiss the progress dialog
     **/
    @Override
    protected void onPostExecute(String file_url) {
        // dismiss the dialog after the file was downloaded
        pDialogkk.dismiss();
        Toast.makeText(context,
                "File Has been Downloaded,Check in your " + "/sdcard/" + getString(R.string.app_name) + "/",
                Toast.LENGTH_LONG).show();
        // Displaying downloaded image into image view
        // Reading image path from sdcard
        // String imagePath = Environment.getExternalStorageDirectory()
        // .toString() + "/downloadedfile.jpg";
        // setting downloaded into image view
    }

}

如何将下载的图像正确保存到应用指定的文件夹

2 个答案: