如何在服务中停止一个线程?在调用stopService方法之后?在Android中

时间:2015-07-23 04:40:05

标签: java android multithreading android-service java-threads

使用服务上传图像

在我的应用程序中我将图像上传到服务器,我使用后台服务来执行此操作,上传在服务中的另一个线程中执行。我已经读过,服务在UI线程和线程中运行服务是另一个过程,我需要的是,我想在按钮点击调用stopService时取消上传。所以我想杀死那个线程,我试过这个代码但是它没有正常工作。可以帮忙吗?拜托?< / p>

    private void uploadPhoto(Bitmap   bitmap) {
    //in this method you upload the photo to the server: omitted for brevity
    Log.e("Method", "uploadPhoto called");
    final Bitmap bit = bitmap;
    flag=true;

           uploadthread = new Thread(new Runnable() {

                    @Override
                    public void run() {

                        Log.e("While", "Inside while loop");
                        try {

                            while (true) {

                                if (flag) {
                                    Log.e("IF", "Inside IF condition"+flag);
                                     return;

                                    //uploadthread.destroy();
                                }
                                handler.sendEmptyMessage(0);
                                // t.sleep(5000);
                                // Toast.makeText(getApplicationContext(), "Horas",
                                // Toast.LENGTH_LONG).show();
                                Log.e("Upload", "Upload Started inside Thread");

                                HttpClient httpClient = new DefaultHttpClient();
                                HttpContext localContext = new BasicHttpContext();
                                HttpPost httpPost = new HttpPost(Config.FILE_UPLOAD_URL);

                                MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);


                                ByteArrayOutputStream bos = new ByteArrayOutputStream();
                                bit.compress(Bitmap.CompressFormat.JPEG, 100, bos);
                                byte[] data = bos.toByteArray();


                                entity.addPart("uploaded_file", new ByteArrayBody(data,
                                        "myImage.jpg"));

                                httpPost.setEntity(entity);

                                HttpResponse response = httpClient.execute(httpPost,
                                        localContext);
                                BufferedReader reader = new BufferedReader(
                                        new InputStreamReader(
                                                response.getEntity().getContent(), "UTF-8"));

                                StringBuilder builder = new StringBuilder();
                                String aux = "";

                                while ((aux = reader.readLine()) != null) {
                                    builder.append(aux);
                                }

                                String sResponse = builder.toString();
                                handler.sendEmptyMessage(0);

                            }
                            }
                            catch(Exception e){
                                e.printStackTrace();
                            }


                          //  stopSelf();
                        }


                });
                uploadthread.start();
              }

onDestroy方法

 @Override
public void onDestroy() {
 try {
        handler.removeCallbacks(uploadthread);
    }
    catch(Exception e)
    {
        e.printStackTrace();
    }
    EndNotification();
    flag = false;
    Log.e("Service", "Service Destroyed");
    Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
    super.onDestroy();


}

2 个答案:

答案 0 :(得分:0)

首先,不要使用线程,使用Async Task,这是处理网络和数据库调用等后台进程的最佳方法。

要从UI取消任何级别的异步任务,您可以使用cancel()方法。

Here是AsyncTask的示例和API。

答案 1 :(得分:0)

你做得对。但是如果我们将你的代码与https://stackoverflow.com/a/21982460/1384010进行比较,那么我只能在调用super.onDestroy()之前设置flag = false。更新你的onDestroy(),如: -

public void onDestroy() { 
    handler.removeCallbacks(t); 
    flag = false;
    super.onDestroy(); 
} 

希望这会对你有所帮助!!