Java如何从AsyncTask返回布尔值？

Z时代
2024-01-10
分类：问答

我有一些EditText，用户可以输入ftp地址，用户名，密码，端口和testConnection按钮。如果成功建立连接，它将返回布尔值true。

boolean status = ftpConnect(_address, _username, _password,_port);
                ftpDisconnect();
                if (status == true) {
                 Toast.makeText(SiteManager.this, "Connection Succesful",
                 Toast.LENGTH_LONG).show();
                 } else {
                 Toast.makeText(SiteManager.this,
                 "Connection Failed:" + status, Toast.LENGTH_LONG).show();
                 }

我正在重新编写代码以使用AsyncTasks执行各种ftp操作，但是，如果连接成功，如何传递布尔值？

testConnection.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                _name = etSitename.getText().toString();
                _address = etAddress.getText().toString();
                _username = etUsername.getText().toString();
                _password = etPassword.getText().toString();
                _port = Integer.parseInt(etPort.getText().toString());
                AsyncConnectTask task = new AsyncConnectTask(SiteManager.this,
                        _address, _username, _password, _port);
                task.execute();
                // boolean status = ftpConnect(_address, _username, _password,
                // _port);
                // ftpDisconnect();
                // if (status == true) {
                // Toast.makeText(SiteManager.this, "Connection Succesful",
                // Toast.LENGTH_LONG).show();
                // savesite.setVisibility(0);
                // } else {
                // Toast.makeText(SiteManager.this,
                // "Connection Failed:" + status, Toast.LENGTH_LONG)
                // .show();
                // }
            }
        });

还有我的AsyncTask

public class AsyncConnectTask extends AsyncTask<Void, Void, Void> {
    private Context mContext;
    private FTPHelper ftpHelper = new FTPHelper();
    private String _address;
    private String _user;
    private String _pass;
    private int _port;
    ProgressDialog progressDialog;
    public AsyncConnectTask(Context context, String address, String user,
            String pass, int port) {
        mContext = context;
        _address = address;
        _user = user;
        _pass = pass;
        _port = port;
    }
    // declare other objects as per your need
    @Override
    protected void onPreExecute() {
        progressDialog = ProgressDialog.show(mContext, "Please wait for ",
                "Process Description Text", true);
        // do initialization of required objects objects here
    };
    @Override
    protected Void doInBackground(Void... params) {
        boolean status = ftpHelper.ftpConnect(_address, _user, _pass, _port);
        return null;
    }
    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        progressDialog.dismiss();
    };
}

回答：

public interface MyInterface {
    public void myMethod(boolean result);
}
public class AsyncConnectTask extends AsyncTask<Void, Void, Boolean> {
    private MyInterface mListener;
    public AsyncConnectTask(Context context, String address, String user,
        String pass, int port, MyInterface mListener) {
        mContext = context;
        _address = address;
        _user = user;
        _pass = pass;
        _port = port;
        this.mListener  = mListener;
    }
    @Override
    protected Boolean doInBackground(Void... params) {
        ....
        return result;
   }
    @Override
    protected void onPostExecute(Boolean result) {
        if (mListener != null) 
            mListener.myMethod(result);
    }
}
AsyncConnectTask task = new AsyncConnectTask(SiteManager.this,
                        _address, _username, _password, _port,  new MyInterface() {
    @Override
    public void myMethod(boolean result) {
        if (result == true) {
            Toast.makeText(SiteManager.this, "Connection Succesful",
            Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(SiteManager.this, "Connection Failed:" + status, Toast.LENGTH_LONG).show();
        } 
    }
});
task.execute();