我正在编写一个请求休息API（Yandex磁盘）的类。我使用排球，但是我确实遇到了一些问题。你可以查看其余的API here。
我使用齐射，我可以在调试器中得到响应，但不是在我的Activity中。
这是我的Requests课程
class Requests {
private String response_of_server, token;
private String url = "https://cloud-api.yandex.net/v1/disk";
private Context context;
Requests (String token, Context context) {
this.token = token;
this.context = context;
}
private void set_response_of_server(String response) {
this.response_of_server = response;
}
String get_response() {
return response_of_server;
}
void get_metadata_of_user() {
try {
/*Request*/
RequestQueue queue = Volley.newRequestQueue(this.context);
Response.ErrorListener error_listener = new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
};
Response.Listener<String> response_listener = new Response.Listener<String>()
{
@Override
public void onResponse(String response) {
set_response_of_server(response);
}
};
StringRequest getRequest = new StringRequest(Request.Method.GET, url+"?fields=user", response_listener, error_listener) {
@Override
public Map<String, String> getHeaders() {
Map<String, String> params = new HashMap<>();
params.put("Host", "cloud-api.yandex.net");
params.put("Authorization", token);
return params;
}
};
queue.add(getRequest);
/*Request end*/
} catch (Exception e) {
e.printStackTrace();
}
}
}
和MainActivity我想要我的回应。
public class MainActivity extends AppCompatActivity {
private final String ID_OF_APP = "Your token of app";
private final String URL_FOR_CODE_QUERY = "https://oauth.yandex.com/authorize?response_type=token&client_id=" + ID_OF_APP;
private String SAVED_TOKEN = "";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn_get_code = findViewById(R.id.btn_get_code); // send to get code page (yandex)
btn_get_code.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse(URL_FOR_CODE_QUERY));
startActivity(i);
}
});
Button btn_sign_in = findViewById(R.id.btn_sign_in);
btn_sign_in.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
EditText code_field = findViewById(R.id.code_field);
String token = code_field.getText().toString();
save_token(token);
try {
if(check_token()) {
//Toast.makeText(MainActivity.this, "You are successfully signed in", Toast.LENGTH_SHORT).show();
// TODO change activity
}
else {}
} catch (InterruptedException e) {
e.printStackTrace();
}
//Toast.makeText(MainActivity.this, "Something went wrong. Please, check your connection and try again later", Toast.LENGTH_SHORT).show();
}
});
}
private void save_token(String token) {
SharedPreferences sPref = getPreferences(MODE_PRIVATE);
SharedPreferences.Editor ed = sPref.edit();
ed.putString(SAVED_TOKEN, token);
ed.apply();
}
private String load_token() {
SharedPreferences sPref = getPreferences(MODE_PRIVATE);
return sPref.getString(SAVED_TOKEN, "");
}
private boolean check_token() throws InterruptedException {
String token = load_token();
String result;
Requests request = new Requests(token, this);
request.get_metadata_of_user();
result = request.get_response();
Toast.makeText(MainActivity.this, result, Toast.LENGTH_SHORT).show();
return !(result.equals("-1"));
}
}
check_token()功能此刻应该只是与服务器的响应举杯。但是，我无法获得Toast或从服务器返回的任何响应。
你有一个Requests类，它具有调用服务器API的功能，即Asynchronous。因此，在你的result函数中调用request.get_metadata_of_user();后，你不会立即得到check_token()。
因此，我建议您修改您的Request类，如下所示。
public class Requests {
private String response_of_server, token;
private String url = "https://cloud-api.yandex.net/v1/disk";
private Context context;
private HttpListener listener; // Add a listener to get the callback functionality
Requests (String token, Context context, HttpListener listener) {
this.token = token;
this.context = context;
this.listener = listener; // initialize the listener here
}
private void set_response_of_server(String response) {
this.response_of_server = response;
listener.onResponseReceived(response); // Send the response back to the calling class
}
String get_response() {
return response_of_server;
}
void get_metadata_of_user() {
try {
RequestQueue queue = Volley.newRequestQueue(this.context);
Response.ErrorListener error_listener = new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
};
Response.Listener<String> response_listener = new Response.Listener<String>()
{
@Override
public void onResponse(String response) {
set_response_of_server(response);
}
};
StringRequest getRequest = new StringRequest(Request.Method.GET, url+"?fields=user", response_listener, error_listener) {
@Override
public Map<String, String> getHeaders() {
Map<String, String> params = new HashMap<>();
params.put("Host", "cloud-api.yandex.net");
params.put("Authorization", token);
return params;
}
};
queue.add(getRequest);
} catch (Exception e) {
e.printStackTrace();
}
}
}
现在HttpListener类可能如下所示。创建HttpListener.java并添加以下代码以将其创建为接口。
public interface HttpListener {
public void onResponseReceived();
}
因此，你需要在你的interface中实现这个MainActivity，如下所示。
public class MainActivity extends AppCompatActivity implements HttpListener {
private final String ID_OF_APP = "Your token of app";
// I fixed this part too. Please change if that is not useful
private final String URL_FOR_CODE_QUERY = "https://oauth.yandex.com/authorize?response_type=" + SAVED_TOKEN + "&client_id=" + ID_OF_APP;
private String SAVED_TOKEN = "";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ... I omitted some code
Button btn_sign_in = findViewById(R.id.btn_sign_in);
btn_sign_in.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
EditText code_field = findViewById(R.id.code_field);
String token = code_field.getText().toString();
save_token(token);
try {
// if(check_token()) {
// The check_token function call is Async. This will not return immediately. Hence you might consider removing this if part. Simply just call the function and listen to the callback function when the response is received
// }
check_token(); // Simply call the function here
} catch (InterruptedException e) {
e.printStackTrace();
}
}
});
}
private void save_token(String token) {
SharedPreferences sPref = getPreferences(MODE_PRIVATE);
SharedPreferences.Editor ed = sPref.edit();
ed.putString(SAVED_TOKEN, token);
ed.apply();
}
private String load_token() {
SharedPreferences sPref = getPreferences(MODE_PRIVATE);
return sPref.getString(SAVED_TOKEN, "");
}
// I changed the return type as this is not returning anything.
private void check_token() throws InterruptedException {
String token = load_token();
String result;
Requests request = new Requests(token, this);
request.get_metadata_of_user();
// You will not get the response immediately here. So omit these codes.
// result = request.get_response();
// Toast.makeText(MainActivity.this, result, Toast.LENGTH_SHORT).show();
// return !(result.equals("-1"));
}
@Override
public void onResponseReceived(String response) {
// Here is your response. Now you can use your response
// and can perform the next action here.
}
}
请注意，代码未经过测试。请根据您的要求进行修改。我希望这有助于您了解问题。