Question

主要活动声明变量类型，用户名和密码

    UsernameEt = (EditText)findViewById(R.id.et_username);
    PasswordEt = (EditText)findViewById(R.id.et_password);

    String username = UsernameEt.getText().toString();
    String password = PasswordEt.getText().toString();
    String type = "login";

    BackgroundWorker backgroundWorker = new BackgroundWorker(this);
    backgroundWorker.execute(type, username, password);

然后BackgroundWorker.java将通过声明params [value]来执行并使用值类型，用户名和密码......

@Override
protected Void doInBackground(String[] voids) {
    String type = this.params[0];

    String login_url = "http://10.0.2.2/ITSP/login.php";
    if(type.equals("login")){
        try {
            String username = this.params[1];
            String password = this.params[2];
            URL url = new URL(login_url);
            HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
            httpURLConnection.setRequestMethod("POST");
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);
            OutputStream outputStream = httpURLConnection.getOutputStream();
            BufferedWriter bufferedWriter =  new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            String post_data = URLEncoder.encode("")
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return null;

但为什么“params [0]”在此代码中未定义？我正在使用android studio 3.1.3版。我应该更换params吗？我该怎么用？

Answer 1

尝试这种方式获得params值

    @Override
protected Void doInBackground(String[] voids) {
    String type = voids[0];

    String login_url = "http://10.0.2.2/ITSP/login.php";
    if(type.equals("login")){
        try {
            String username = voids[1];
            String password =voids[2];
            URL url = new URL(login_url);
            HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
            httpURLConnection.setRequestMethod("POST");
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);
            OutputStream outputStream = httpURLConnection.getOutputStream();
            BufferedWriter bufferedWriter =  new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            String post_data = URLEncoder.encode("")
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return null;

Params错误取消定义

1 个答案: