android - How to perform multiple related calls to AsyncTasks without overlapping? -


I have an application that needs to call repeatedly for web API, effectively, this SQL table Repeats according to the record and makes a unique call to the web server with appropriate data. This is a kind of data synchronization

As I understand when requesting this kind of HTTP request for an API, this UI should be within an AsyncTask to avoid hanging, so I Your AsyncTask class has made a request that parses back and parses feedback, but I need to back this data into the calling class.

Above him, I do not want calling classes to run these requests in parallel. I want to make this a request, and do not want to repeat the next record in the table and the second request should not be made until the first request ends. So in a way, I want to block it, but still in a different thread, so that the UI is not static. At least, I think that's what I want.

Pseudo code is something on the lines of this: 

  // caller function synchronize public null () {Load all records from SQL table for each record: if Record type is X: new asyncX (). Execute (records) // After this successfully completes, // I want to do something with the return value here, // before going to the next recurrence // when some UI here, // some nice spine Show logo and possibly // some text // if the record type is Y: new asyncY (). Execute (records) // Like the above // ​​// async class public class asyncTask in AsyncX and lt; RecordType, Zero, Record Type and gt; {Type secure recordindexgrounds (record type ... records) {Jason Make HTTP response to HTML response parsing response Return record}}   
 The way I'm thinking of doing this, change it The synchronized function to run a record at once, call the async function, and finish, and then return the async function back to the synchronize_followup () function which returns that return Need to be done with the price, and then syncs back again again, but I'm not sure I like it.  
 How to consider moving forward?  
 
 The way you want to handle it has already been invented with threading synchronization , So you implement it your way.  
  Semaphore is a class similar to  CountDownLatch  name. When you declare an object, and activate the lock mechanism through  .wait () , you do not issue a  .countdown ()  statement By doing so, it will stabilize and execute code. Actually, if you can declare , then perhaps that effect will be seen by you.  
 This is a good example of how to prevent a  thread  execution based on the execution of another.

Comments

Post a Comment

Popular posts from this blog

Java - Error: no suitable method found for add(int, java.lang.String) -

I'm in the middle of homework work and I'm stuck. At this point in my code, I think that I should have a GUI window that opens and allows me to type "inserted text number". Notice is not going anywhere but at this point, If I pass through the problem then it will be in a linked list. I am getting two of the same error for the lines. Add (index, element); And I can not seem to get past it, there is no suitable method for the error "add (int, java. string string)". Code is below, please advise. To clarify - this will not be a method error because it is a linked list. There should not be any way involved. import java.awt. *; Import java.awt.event. *; Import javax.swing. *; Import java.util. *; Import java.util.Scanner; Import java.util.LinkedList; Public class TopTenList JFrame {Private TopTenList tt; See the Private JTextArea list; Private JTextField cmdTextField; Private JTextField resultsTestfield; // This GUI window is the code for the public toptist...
Read more

java - JPA TypedQuery: Parameter value element did not match expected type -

I am using JPA 2.0 and getting the following code in the DAO layer: Public Zero Test () {string key = "status"; String [] Conditions = {"A", "B"}; & Lt; TestTable & gt; Results = Search (Keys, Conditions); } Public listing & lt; TestTable & gt; Search (string key, object value error) {string sql = "test ndf to testlet and jade nand." + Key + "in:" + key; TypedQuery & LT; TestTable & gt; Query = entityManager.createQuery (SQL, TestTable.class); Query.setParameter (key, Arrays.asList (valueArr)) / *** Error Line *** Return query.getResultList (); } In the above error line, it throws the following exception: java.lang.IllegalArgumentException: parameter value element [[Ljava.lang.String; @ cbe5bc] did not match the expected type [java.lang.String] Why is this expected type string while actually this string []? Please help! Note: This is derived from the normal routine and is a simplified code. I can no...
Read more

c++ - static template member variable has internal linkage but is not defined -

Yes, I know, there is a question with almost the same title, but it refers to a different situation. Error message) In my case, I have a .cpp file with a big named designation name (implementation details). There is a property class template with a static data member in that name space, which I need to access from outside the unknown namespace. I give it a little bit of meat: file.hpp namespace Bar {template & lt; Typename A & gt; Struct foo {static_assert (is_same & lt; a, float & gt; :: value} is_same & lt; a, double>: value, ""); Fixed zero set_static_var (a const & x); // ...}; } and file.cpp namespace {template & lt; Typename A & gt; Struct foo_traits {// supports the implementation of several static code bars: foo & lt; & Gt; Fixed A data; }; The template's & lt; & Gt; Float foo_traits & lt; Float & gt; :: datum; // No change if this is in the global namespace template & lt; & Gt; Doub...
Read more