Question

我正在尝试使用一个在我的应用程序中传递的简单对象类。首先，我用它来执行AsyncTask。在AsyncTask的const electron = require('electron') const fs = require('fs') const app = electron.app const BrowserWindow = electron.BrowserWindow const Menu = electron.Menu const Tray = electron.Tray const ipc = electron.ipcMain const path = require('path') const url = require('url') const shell = electron.shell let mainWindow ipc.on('print-to-pdf', function (event) { const pdfPath = path.join(__dirname, '/reports/print.pdf') const win = BrowserWindow.fromWebContents(event.sender) win.webContents.printToPDF({printBackground: true, landscape: true}, function (error, data) { if (error) throw error fs.writeFile(pdfPath, data, function (error) { if (error) { throw error } shell.openExternal('file://' + pdfPath) event.sender.send('wrote-pdf', pdfPath) }) }) })方法中，我想让这个相同的对象类再次使用它的一些setter。如何将此onPostExecute对象传递给AsyncTask的data和doInBackground？

代码：

TravelPlanner.java

onPostExecute

GetInfo.java

// Put departure & arrival into model class
data = new ReisData();
data.setDeparture(departureStation);
data.setArrival(arrivalStation);

// Start AsyncTask
GetInfo asyncTask = new GetInfo(this);
asyncTask.execute(data);

Answer 1

您可以传递AsyncTask

的 Contructor

TravelPlanner.java

// Put departure & arrival into model class
data = new ReisData();
data.setDeparture(departureStation);
data.setArrival(arrivalStation);

// Start AsyncTask
GetInfo asyncTask = new GetInfo(this,data); // here is
asyncTask.execute(data);

GetInfo.java

public class GetInfo extends AsyncTask<ReisData, Integer, String> {
ReisData data;
Reisplanner reisPlanner;
View view;

public GetInfo(Reisplanner main,ReisData data) {
this.data=data;// you can use this
this.reisPlanner = main;

view = reisPlanner.getView();
}

@Override
protected void onPreExecute() {
ProgressBar progressBar = (ProgressBar) view.findViewById(R.id.progressBar);
progressBar.setVisibility(View.VISIBLE);
super.onPreExecute();

}
@Override
protected String doInBackground(ReisData... params) {
try {
    // Return XML as string with route options
    return HttpRequestHelper.downloadFromServer(params);
} catch (MalformedURLException e) {
    e.printStackTrace();
}
return null;
}

@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);

DocumentBuilder builder;
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

Document doc = null;

try {
    builder = factory.newDocumentBuilder();
    doc = builder.parse(new InputSource(new StringReader(result)));
} catch (Exception e) {
    e.printStackTrace();
}

// TODO: Get 'ReisData' object

if (doc != null) {
    XMLParser.parse(doc);
}

// Start Reisadvies with ReisData class
Fragment fragment = new Reisadvies();

// TODO: Put ReisData class into Bundle

this.reisPlanner.startFragment(fragment);

}

将对象从Fragment传递给ASyncTask onPostExecute

1 个答案: