异步任务：将两个或多个值从 doInBackground 传递到 onPostExecute

android java android-asynctask

2022-09-01 19:56:07

我有一个Asynctask，它检索两个int vaules，我想将它们传递给onPostExecute以在视图上显示它们。
这是我的代码：

    public class QueryServer extends AsyncTask <String, Void, Integer> { 

    protected Integer doInBackground(String... serverAddress) {
        Log.d("QueryServer", ""+serverAddress[0]);
        MCQuery mcQuery = new MCQuery("" + serverAddress[0] ,25565);
        QueryResponse response = mcQuery.basicStat();

        int Onlineplayers = response.getOnlinePlayers(); //first vaule
        int Maxplayers = response.getMaxPlayers();  //second vaule

        Log.d("MCQuery", "" + Onlineplayers + " OnlinePlayers");
        return Onlineplayers;

    }

    protected void onPostExecute(Integer Onlineplayers){

        TextView onlinePlayersView = (TextView) findViewById(R.id.online_players);

        onlinePlayersView.setText(""+Onlineplayers+"/"+ Maxplayers); //i need to pass Maxplayers to use it here


    }

提前感谢您。

答案 1

您可以定义一个包含两个整数的 Wrapper 类：

public class Wrapper
{
    public int onlinePlayers;
    public int maxPlayers;
}

并将其用于代替：Integer

public class QueryServer extends AsyncTask<String, Void, Wrapper> { 

    protected Wrapper doInBackground(String... serverAddress) {
        Log.d("QueryServer", ""+serverAddress[0]);
        MCQuery mcQuery = new MCQuery("" + serverAddress[0] ,25565);
        QueryResponse response = mcQuery.basicStat();

        int onlinePlayers = response.getOnlinePlayers(); //first vaule
        int maxPlayers = response.getMaxPlayers();  //second vaule

        Log.d("MCQuery", "" + onlinePlayers + " onlinePlayers");
        Wrapper w = new Wrapper();
        w.onlinePlayers = onlinePlayers;
        w.maxPlayers = maxPlayers;
        return w;

    }

    protected void onPostExecute(Wrapper w){

        TextView onlinePlayersView = (TextView) findViewById(R.id.online_players);

        onlinePlayersView.setText(""+w.onlinePlayers+"/"+ w.maxPlayers); //i need to pass Maxplayers to use it here


    }

答案 2

public class QueryServer extends AsyncTask <String, Void, Integer>{...}

将通用参数替换为或IntegerArrayList<Integer>Integer[]

这样，您的遗嘱将如下所示：doInBackground()

protected Integer[] doInBackground(String... serverAddress) 
{
    ...do what you need to do...
    //Then create an array, fill with data, and return.
    Integer[] arr = new Integer[10];
    for(int i=0; i<10; i++)
        arr[i] = i; //just an example
    return arr;
}

而在你的onPostExecute()

protected void onPostExecute(Integer [] Onlineplayers)
{
    //Do whatever you want with your array
}