Reputation: 7055
I'm designing an application that frequently communicates to a web server for updates. Communication happens only when user requests. I found AsyncTask could be helpful here. So I modified one class to serve my application as AsyncTask.
I want to pass an url and http post parameters to anysc class's doInBackground process. I can't figure out how to do it.
Here's it-
public class GetXMLFromServer extends
AsyncTask< String, Void, String> {
private Context context;
GetXMLCallback gc = null;
ProgressDialog progressDialog;
public GetXMLFromServer(Context context, GetXMLCallback gc) {
this.context = context;
this.gc = gc;
progressDialog = new ProgressDialog(this.context);
}
protected void onPreExecute() {
progressDialog.setMessage("Fetching...");
progressDialog.show();
}
@Override
protected void onPostExecute(String result) {
gc.onSuccess(result);
progressDialog.dismiss();
}
@Override
protected String doInBackground(String... params) {
String response = "";
response=CustomHttpClient.executeHttpPost(params[0]);
return null;
}
//Confused how to pass URL and http post parameters to doInBackground().
}
I've one interface that is used to process response sent from onPostExecute(). It is as fallows.
package com.project.main.external;
public interface GetXMLCallback {
void onSuccess(String downloadedString);
void onFailure(Exception exception);
}
And here is my main activity that calls for http response --
public class UpdateList extends Activity implements GetXMLCallback {
//above line also throws error that interface methods are not implemented yet
//they are (few lines below) defined.
private TextView textView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.list_layout);
textView = (TextView) findViewById(R.id.TextView01);
}
GetXMLCallback gc = new GetXMLCallback() {
public void onFailure(Exception exception) {
}
public void onSuccess(String downloadedString) {
textView.setText(downloadedString);
}
};
public void getUpdates(View view) {
GetXMLFromServer task = new GetXMLFromServer(UpdateList.this, gc);
task.execute(WebConstants.GET_UPDATES);
}
}
Upvotes: 4
Views: 3602
Reputation: 7295
public class GetXMLFromServer extends
AsyncTask< String, Void, String> {
private Context context;
GetXMLCallback gc = null;
ProgressDialog progressDialog;
public Type variable1;
public Type variable2;
and set up the variables:
GetXMLFromServer task = new GetXMLFromServer(UpdateList.this, gc);
task.variable1 = XXXXX;
task.variable2 = XXXXX;
task.execute(WebConstants.GET_UPDATES);
Upvotes: 0
Reputation: 5407
AsyncTask does already allow more parameters:
In your case call it like this:
task.execute("parameter_one","parameter_two","parameter_three");
In doInBackground you can get them with:
params[0]
params[1]
params[2]
And so on
Just notice that all parameters must be of the same Type, in your case String.
Upvotes: 10
Reputation: 40734
doInBackground
AsyncTask<HttpPost, Void, String>
or AsyncTask<SOME_CLASS, Void, String>
where SOME_CLASS is an ArrayList of Strings, a HashMap, or some other class that you could create that would contain everything you need to construct the HttpPostUpvotes: 4