Android saving to external SD card?

问题

Hey guys can someone tell me why i cannot save this file to the external sd? Can you check over my code?

 public void Download()
  {
      try {
            //this is the file you want to download from the remote server
            String path ="http://mozilla.cdn.leaseweb.com/firefox/releases/4.0.1/win32/en-US/Firefox%20Setup%204.0.1.exe";
            //this is the name of the local file you will create
            String targetFileName;
                boolean eof = false;
            URL u = new URL(path);
            HttpURLConnection c = (HttpURLConnection) u.openConnection();
            c.setRequestMethod("GET");
            c.setDoOutput(true);
            c.connect();

            //String svto = Environment.getExternalStorageState().toString();
            File path1 = Environment.getExternalStoragePublicDirectory(
                    Environment.DIRECTORY_PICTURES);

            path1.mkdirs();
            FileOutputStream f = new FileOutputStream(new File(path1+"/fox.exe"));
                InputStream in = c.getInputStream();
                byte[] buffer = new byte[1024];
                int len1 = 0;
                while ( (len1 = in.read(buffer)) !=  -1 ) {
                f.write(buffer,0, len1);
                         }
            f.close();
            } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            } catch (ProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

  }

回答1:

This operation will fail if you don't have the following permissions in your AndroidManifest.xml file:

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

Make sure to put them within the top-level <manifest> tag, not the <application> tag where your activities are specified.

回答2:

I had a problem similar to this before. It turned out that I had to manually create the directory first on the SD card before calling code such as Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);

Check if the absolute path exists on your file explorer for that directory. If it doesn't, then create it via adb shell and then give it a try again. This solved my problem, but it may not necessarily solve yours, give it a try though!

来源：https://stackoverflow.com/questions/5837300/android-saving-to-external-sd-card

标签

java

android

sd-card