java - 异步任务 : class should be static or leaks might occur

Question

我正在尝试创建一个从 http 请求返回 json(使用 org.json 依赖项)的函数。要在 Android Java 中执行此操作，必须创建一个 AsyncTask

public class MainActivity extends AppCompatActivity {

TextView resultQuery;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    resultQuery = findViewById(R.id.resultQuery);
    try {
        new sendUrl().execute();

    } catch (Exception e) {
        e.printStackTrace();
        resultQuery.setText("Erro: " + e);
        Toast.makeText(this, "Erro" + e, Toast.LENGTH_SHORT).show();
    }
}

private class sendUrl extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params){

        try {
            call_me();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }

    @Override
    protected void onPostExecute(String message){
        Toast.makeText(MainActivity.this, "PostExecute", Toast.LENGTH_SHORT).show();
    }
}

public void call_me() throws Exception {
    String url = "https://api.github.com/users/leonanml";
    URL obj = new URL(url);
    HttpURLConnection con = (HttpURLConnection) obj.openConnection();
    // optional default is GET
    con.setRequestMethod("GET");
    //add request header
    con.setRequestProperty("User-Agent", "Mozilla/5.0");
    int responseCode = con.getResponseCode();
    //System.out.println("\nSending 'GET' request to URL : " + url);
    Toast.makeText(this, "Response Code : " + responseCode, Toast.LENGTH_SHORT).show();
    BufferedReader in = new BufferedReader(
            new InputStreamReader(con.getInputStream()));
    String inputLine;
    StringBuffer response = new StringBuffer();
    while ((inputLine = in.readLine()) != null) {
        response.append(inputLine);
    }
    in.close();
    //print in String
    //System.out.println(response.toString());
    //Read JSON response and print
    JSONObject myResponse = new JSONObject(response.toString());
    //System.out.println("result after Reading JSON Response");
    //System.out.println("id: "+myResponse.getString("login"));
    resultQuery.setText(response.toString());
}}

目前我的“sendUrl”类发出警告:

This AsyncTask class should be static or leaks might occur (com.muller.httprequest.MainActivity.sendUrl) Inspection info:A static field will leak contexts.

Answer 1

当你使用一个非静态的内部类时，它不能被垃圾收集器收集，所以它会继续使用内存，简单的解决方法是将内部类设为静态或使其脱离 Activity 类。