Android 使用回调接口实现异步任务-在单个回调接口中处理多个调用响应
在我的Android应用程序中,我从一个活动中调用多个API。我使用以下方法:在活动中实现接口,并从异步类调用该接口函数Android 使用回调接口实现异步任务-在单个回调接口中处理多个调用响应,android,android-asynctask,Android,Android Asynctask,在我的Android应用程序中,我从一个活动中调用多个API。我使用以下方法:在活动中实现接口,并从异步类调用该接口函数 public interface AsyncResponse { public void processFinish(JSONObject sb); } public class FetchData extends AsyncTask<String, Integer, JSONObject> { HttpURLConnection urlCon
public interface AsyncResponse {
public void processFinish(JSONObject sb);
}
public class FetchData extends AsyncTask<String, Integer, JSONObject> {
HttpURLConnection urlConnection;
String url;
String method;
String payload = null;
AsyncResponse delegate = null;
public FetchData(AsyncResponse delegate, String url, String method) {
this.delegate = delegate;
this.url = url;
this.method = method;
}
public FetchData(AsyncResponse delegate, String url, String method, JSONObject payload) {
this(delegate, url, method);
this.payload = payload.toString();
}
@Override
protected JSONObject doInBackground(String... args) {
BufferedReader reader = null;
try {
URL url = new URL(this.url);
// Open HTTP connection
urlConnection = (HttpURLConnection) url.openConnection();
// HTTP method GET/POST/PUT/DELETE
urlConnection.setRequestMethod(this.method);
// handle issues
int statusCode = urlConnection.getResponseCode();
// Get the response
InputStream inputStream = urlConnection.getInputStream();
if(inputStream == null) {
// Nothing to do
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
String inputLine = null;
StringBuffer response = new StringBuffer();
while ((inputLine = reader.readLine()) != null) {
response.append(inputLine + "\n");
}
return new JSONObject(response.toString());
} catch(Exception e) {
try {
// Return error response
} catch(Exception e1) {
System.out.println(e1);
return null;
}
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e("PlaceholderFragment", "Error closing stream", e);
}
}
}
}
@Override
protected void onPostExecute(JSONObject result) {
super.onPostExecute(result);
this.delegate.processFinish(result);
}
}
public class AsyncTasks extends AppCompatActivity implements AsyncResponse {
TextView view = null;
int a = 1;
Utility utility = Utility.getInstance();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_async_tasks);
new FetchData(this, "<url 1>", "GET").executeOnExecutor(THREAD_POOL_EXECUTOR);
new FetchData(this, "<url 2>", "GET").executeOnExecutor(THREAD_POOL_EXECUTOR);
}
@Override
public void processFinish(JSONObject data) {
utility.showDialog(this, data.toString());
}
}
公共接口异步响应{
公共无效处理完成(JSONObject sb);
}
公共类FetchData扩展异步任务{
HttpURLConnection-urlConnection;
字符串url;
字符串方法;
字符串有效负载=null;
AsyncResponse委托=null;
公共FetchData(异步响应委托、字符串url、字符串方法){
this.delegate=委托;
this.url=url;
这个方法=方法;
}
公共FetchData(异步响应委托、字符串url、字符串方法、JSONObject负载){
这(委托、url、方法);
this.payload=payload.toString();
}
@凌驾
受保护的JSONObject doInBackground(字符串…args){
BufferedReader reader=null;
试一试{
URL=新URL(this.URL);
//打开HTTP连接
urlConnection=(HttpURLConnection)url.openConnection();
//HTTP方法GET/POST/PUT/DELETE
urlConnection.setRequestMethod(this.method);
//处理问题
int statusCode=urlConnection.getResponseCode();
//得到回应
InputStream InputStream=urlConnection.getInputStream();
如果(inputStream==null){
//无事可做
返回null;
}
reader=新的BufferedReader(新的InputStreamReader(inputStream,“UTF-8”));
字符串inputLine=null;
StringBuffer响应=新的StringBuffer();
而((inputLine=reader.readLine())!=null){
响应。追加(inputLine+“\n”);
}
返回新的JSONObject(response.toString());
}捕获(例外e){
试一试{
//返回错误响应
}捕获(异常e1){
系统输出打印LN(e1);
返回null;
}
}最后{
if(urlConnection!=null){
urlConnection.disconnect();
}
if(读卡器!=null){
试一试{
reader.close();
}捕获(最终IOE例外){
Log.e(“占位符片段”,“错误关闭流”,e);
}
}
}
}
@凌驾
受保护的void onPostExecute(JSONObject结果){
super.onPostExecute(结果);
this.delegate.processFinish(结果);
}
}
公共类AsyncTasks扩展AppCompatActivity实现AsyncResponse{
TextView=null;
INTA=1;
Utility=Utility.getInstance();
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity\u async\u tasks);
新的FetchData(this,,“GET”).executeOnExecutor(线程池执行器);
新的FetchData(this,,“GET”).executeOnExecutor(线程池执行器);
}
@凌驾
公共void processFinish(JSONObject数据){
utility.showDialog(this,data.toString());
}
}
这里如何在processFinish()接口函数中处理第二个GET调用的响应?最好的方法是什么?公共接口异步响应{
public interface AsyncResponse {
//Add requestCode to identify request.
public void processFinish(JSONObject sb, int requestCode);
}
public class FetchData extends AsyncTask<String, Integer, JSONObject> {
HttpURLConnection urlConnection;
String url;
String method;
String payload = null;
AsyncResponse delegate = null;
int requestCode;
public FetchData(String url, String method) {
this(url, method, null);
}
public FetchData(String url, String method, JSONObject payload) {
this.url = url;
this.method = method;
if(payload!=null){
this.payload = payload.toString();
}
}
//You can set AsyncResponse and RequestCode in constructor also.
public FetchData setListener(AsyncResponse asyncResponse, int requestCode){
this.delegate = asyncResponse;
this.requestCode = requestCode;
return this;
}
@Override
protected JSONObject doInBackground(String... args) {
....
}
@Override
protected void onPostExecute(JSONObject result) {
super.onPostExecute(result);
if(delegate!=null){
//post result with given requestCode
this.delegate.processFinish(result, requestCode);
}
}
}
public class AsyncTasks extends AppCompatActivity implements AsyncResponse {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_async_tasks);
// Make first call with request code as 1
new FetchData("<url 1>", "GET").setListener(this, 1).executeOnExecutor(THREAD_POOL_EXECUTOR);
// Make second call with request code as 2
new FetchData("<url 2>", "GET").setListener(this, 2).executeOnExecutor(THREAD_POOL_EXECUTOR);
}
@Override
public void processFinish(JSONObject data, int requestCode) {
switch(requestCode){
case 1:
//perform task on 1st call finish
break;
case 2:
utility.showDialog(this, data.toString());
//perform task on 2nd call finish
break;
}
}
}
//添加requestCode以标识请求。
公共void processFinish(JSONObject sb,int requestCode);
}
公共类FetchData扩展异步任务{
HttpURLConnection-urlConnection;
字符串url;
字符串方法;
字符串有效负载=null;
AsyncResponse委托=null;
int请求码;
公共获取数据(字符串url、字符串方法){
这个(url、方法、null);
}
公共获取数据(字符串url、字符串方法、JSONObject负载){
this.url=url;
这个方法=方法;
如果(有效负载!=null){
this.payload=payload.toString();
}
}
//您还可以在构造函数中设置AsyncResponse和RequestCode。
公共FetchData setListener(AsyncResponse AsyncResponse,int requestCode){
this.delegate=asyncResponse;
this.requestCode=requestCode;
归还这个;
}
@凌驾
受保护的JSONObject doInBackground(字符串…args){
....
}
@凌驾
受保护的void onPostExecute(JSONObject结果){
super.onPostExecute(结果);
如果(委托!=null){
//使用给定的请求代码发布结果
this.delegate.processFinish(结果、请求代码);
}
}
}
公共类AsyncTasks扩展AppCompatActivity实现AsyncResponse{
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity\u async\u tasks);
//使用请求代码1进行第一次呼叫
新的FetchData(“,”GET“).setListener(this,1).executeOnExecutor(线程池执行器);
//进行第二次呼叫,请求代码为2
新的FetchData(“,”GET“).setListener(this,2).executeOnExecutor(线程池执行器);
}
@凌驾
公共void processFinish(JSONObject数据,int请求代码){
开关(请求代码){
案例1:
//在第一次呼叫完成时执行任务
打破
案例2:
utility.showDialog(this,data.toString());
//在第二次呼叫完成时执行任务
打破
}
}
}
也许我晚了一点。
但是我和你面临着同样的问题,验证答案中的这个切换案例让我非常恼火,所以在这里,你可以找到一种方法,使用匿名异步响应实现任意多的请求
在中,当您传递AsyncTasks类以通过实现管理回调时,将获取数据
public interface AsyncResponse {
//Add requestCode to identify request.
public void processFinish(JSONObject sb, int requestCode);
}
public class FetchData extends AsyncTask<String, Integer, JSONObject> {
HttpURLConnection urlConnection;
String url;
String method;
String payload = null;
AsyncResponse delegate = null;
int requestCode;
public FetchData(String url, String method) {
this(url, method, null);
}
public FetchData(String url, String method, JSONObject payload) {
this.url = url;
this.method = method;
if(payload!=null){
this.payload = payload.toString();
}
}
//You can set AsyncResponse and RequestCode in constructor also.
public FetchData setListener(AsyncResponse asyncResponse, int requestCode){
this.delegate = asyncResponse;
this.requestCode = requestCode;
return this;
}
@Override
protected JSONObject doInBackground(String... args) {
....
}
@Override
protected void onPostExecute(JSONObject result) {
super.onPostExecute(result);
if(delegate!=null){
//post result with given requestCode
this.delegate.processFinish(result, requestCode);
}
}
}
public class AsyncTasks extends AppCompatActivity{
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_async_tasks);
// Make first call with request code as 1. Use anonym callBack implementation
new FetchData("<url 1>", "GET").setListener(new AsyncResponse () {
@Override
public void processFinish(JSONObject sb, int requestCode) {
//perform task on 1st call finish
}
}, 1).executeOnExecutor(THREAD_POOL_EXECUTOR);
// Make second call with request code as 2
new FetchData("<url 2>", "GET").setListener(new AsyncResponse () {
@Override
public void processFinish(JSONObject sb, int requestCode) {
//perform task on 2st call finish
}
}, 2).executeOnExecutor(THREAD_POOL_EXECUTOR);
// Make as many call to FetchData and implement an anonym AsyncResponse each time
}