我即将编写一个小应用程序。点击按钮后,我会在自定义异步任务类中发送一个http请求。我想在EditText字段和ListView中将这个值写入项目。我现在的问题是我想将请求的值返回到主线程以进一步处理它。我搜索了一下,发现了一个带有界面的方法。这是我的AsyncTask类:Android - 在按钮上使用AsyncTask发送HTTP请求单击|代表问题
public class Request extends AsyncTask<String,Void,String> {
public AsyncResponse delegate=null;
private MainActivity mAct;
public Request(MainActivity mainActivity){
this.mAct = mainActivity;
}
@Override
protected String doInBackground(String... url){
String returnString = "";
try {
URL u = new URL(url[0]);
final HttpURLConnection connection = (HttpURLConnection)u.openConnection();
BufferedInputStream bis = new BufferedInputStream(connection.getInputStream());
byte[] content = new byte[1024];
int bytesRead = 0;
String strContent = "";
while((bytesRead = bis.read(content)) != -1){
strContent += new String(content,0,bytesRead);
}
returnString = strContent;
} catch (Exception e){
} finally {
return returnString;
}
}
protected void onPostExecute(String result){
delegate.processFinish(result);
}
}
这是我的MainActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button btnSend = (Button)findViewById(R.id.btnSendMessage);
final ListView lv = (ListView)findViewById(R.id.treeView);
final EditText editText = (EditText)findViewById(R.id.txtReqID);
final MainActivity ma = this;
final ArrayList<String> arrList = new ArrayList<String>();
final ArrayAdapter<String> arrAdapter = new ArrayAdapter<String>(getApplicationContext(),R.layout.simple_list_item_1,arrList);
btnSend.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
String t = new String("http://myhttprequest");
Request r = new Request(ma);
public void onCreate(Bundle savedInstanceState){
r.delegate = this;
}
editText.setText(returnValue);
lv.setAdapter(arrAdapter);
arrList.add(returnValue);
arrAdapter.notifyDataSetChanged();
}
});
}
public interface AsyncResponse{
void processFinish(String output);
}
的问题是,我必须每一个变量声明为final,因为我在函数内部存取权限它们。我现在对我的代码感到不高兴,我也不知道如何让这项工作。很感谢任何形式的帮助。
致以问候
我不明白这是如何用'setOnClickListener'内的代码可以解决问题。如果你能给我一个简短的代码示例,我会非常感激。 – binaryBigInt