Question

这是我的代码。当我运行此代码显示错误。帮助我，我已经浪费了很多时间来完成这项任务。

public class AndroidDownloadFileByProgressBarActivity extends Activity {

    // button to show progress dialog
    Button btnShowProgress;
    MediaController mediaController ;
    // Progress Dialog
    private ProgressDialog pDialog;
    VideoView videoView;
    // Progress dialog type (0 - for Horizontal progress bar)
    public static final int progress_bar_type = 0; 

    // File url to download
    private static String file_url = "http://192.168.1.107/MSEManagement/static/uploads/productIntroduction/4/4.mp4";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // show progress bar button
        btnShowProgress = (Button) findViewById(R.id.btnProgressBar);
        // Image view to show image after downloading
        //videoView = (VideoView) findViewById(R.id.my_image);
        /**
         * Show Progress bar click event
         * */
        btnShowProgress.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // starting new Async Task
                new DownloadFileFromURL().execute(file_url);
            }
        });
    }

    /**
     * Showing Dialog
     * */
    @Override
    protected Dialog onCreateDialog(int id) {
        switch (id) {
        case progress_bar_type:
            pDialog = new ProgressDialog(this);
            pDialog.setMessage("Downloading file. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setMax(100);
            pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            pDialog.setCancelable(true);
            pDialog.show();
            return pDialog;
        default:
            return null;
        }
    }

    class DownloadFileFromURL extends AsyncTask<String, String, String> {


        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            showDialog(progress_bar_type);
        }

        /**
         * Downloading file in background thread
         * */
        @Override
        protected String doInBackground(String... f_url) {
            int count;
            try {
                URL url = new URL(f_url[0]);
                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/4.mp4");

                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);
                }


                output.flush();

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

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

            return null;
        }


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


        @Override
        protected void onPostExecute(String file_url) {
            // dismiss the dialog after the file was downloaded
            dismissDialog(progress_bar_type);

            // Displaying downloaded image into image view
            // Reading image path from sdcard
            videoView =(VideoView)findViewById(R.id.videoView);

            mediaController= new MediaController(AndroidDownloadFileByProgressBarActivity.this);
            mediaController.setAnchorView(videoView);

            Uri uri=Uri.parse("/sdcard/4.mp4");
            videoView.setMediaController(mediaController);
            videoView.setVideoURI(uri);
            videoView.requestFocus();
            videoView.start();
          }

    }

当我在手机上运行我的代码时，它运行但不能正常运行的android模拟器。我现在应该怎么做才能坚持这些事情。

D / VideoView：错误：1,0

E /错误:: /sdcard/4.mp4（权限被拒绝）

W / MediaPlayer：无法打开/sdcard/4.mp4:java.io.FileNotFoundException：没有内容提供者：/sdcard/4.mp4

W / VideoView：无法打开内容：/sdcard/4.mp4

         java.io.FileNotFoundException: /sdcard/4.mp4 (Permission denied)

Answer 1

如果您的应用在手机上正常运行且无法在模拟器上运行，这些都可能发生

您的清单文件应包含

等权限

<uses-permission android:name="android.permission.INSTALL_PACKAGES" />
<uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

也许您的手机SDK版本和模拟器有不同的sdk尝试与您的手机相同的sdk版本模拟器。

我想从网址下载图片并将其保存到设备的内存并成功保存后播放？

1 个答案: