android doinbackground toast,如何根据AsyncTask的结果在受保护的字符串doInBackground方法中调用Toast.makeText（）？...

我从AsyncTask中的数据库中提取数据，如果它为null，我想Toast一个警告文本。我在AsyncTask中尝试过，但我知道它不在工作线程中调用。这里是我的doInBackground方法：如何根据AsyncTask的结果在受保护的字符串doInBackground方法中调用Toast.makeText()？

protected String doInBackground(Boolean... params) {

String result = null;

StringBuilder sb = new StringBuilder();

try {

HttpClient httpclient = new DefaultHttpClient();

HttpGet httppost = new HttpGet("http://191.162.2.235/getProducts.php?login=1&user_name="+UserName+"&user_pass="+Password);

HttpResponse response = httpclient.execute(httppost);

if (response.getStatusLine().getStatusCode() != 200) {

Log.d("MyApp", "Server encountered an error");

}

BufferedReader reader = new BufferedReader(

new InputStreamReader(

response.getEntity().getContent(), "UTF8"));

sb = new StringBuilder();

sb.append(reader.readLine() + "\n");

String line = null;

while ((line = reader.readLine()) != null) {

sb.append(line + "\n");

}

result = sb.toString();

if ( result == null ) {

// Toast.makeText(getApplicationContext(), "You entered wrong values.", Toast.LENGTH_LONG).show();

asyncTask.cancel(true);

Intent inte=new Intent(MainActivity.this, MainActivity.class);

inte.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

inte.addCategory(Intent.CATEGORY_HOME);

startActivity(inte);

}

}

catch (Exception e) {

Log.e("log_tag", "Error converting result " + e.toString());

}

return result;

}

我取消了任务，创造在我的代码的新意图。你不关心他们。你看到Toast.makeText ..线，我尝试像这样当然会给出错误。我怎样才能做到这一点？如果它没有在AsyncTask中调用，我应该怎么调用？

2013-10-10

elfoz

+1

你可以发布错误吗？ –