logo
down
shadow

how come Thread class called inside another class?


how come Thread class called inside another class?

By : user2956407
Date : November 22 2020, 10:56 AM
I wish did fix the issue. Yes it is possible, your code is a proof of this. You can always use static members of a given class without instanciating the class. Roughly, in Java every class is an object that you don't have to instanciate, on which you can call its static methods.
What you can't do is to create a useful Thread without implementing the Runnable interface or extending the Thread class. (You can create a Thread without doing so by instanciating the Thread class directly, but such a thread will not be useful).
code :


Share : facebook icon twitter icon
Error in derived TimerTask class: `Can't create handler inside thread that has not called Looper.prepare()`

Error in derived TimerTask class: `Can't create handler inside thread that has not called Looper.prepare()`


By : Jeffrey Gosian
Date : March 29 2020, 07:55 AM
This might help you Timertask runs on a different thread. So you cannot not update/access ui from a background thread.
Probably m_MyLayout.doReload() is updating ui. Use a Handler or runOnUiThread
code :
 runOnUiThread(new Runnable() {

                        @Override
                        public void run() {
                            m_MyLayout.doReload()
                        }
                    });
 Handler m_handler;
 Runnable m_handlerTask ;
      m_handler = new Handler();
       m_handlerTask = new Runnable()
       {
           @Override 
           public void run() { 
              // do something
                m_handler.postDelayed(m_handlerTask, 1000);
                  // repeat some task every 1 second    

           }
      };
      m_handlerTask.run(); 
m_handler.removeCallbacks(m_handlerTask);
Are class instances thread-safe when called and destroyed inside a single thread?

Are class instances thread-safe when called and destroyed inside a single thread?


By : gibson vuyani Mdlane
Date : March 29 2020, 07:55 AM
I hope this helps . 1) Yes, if their scope doesn't reach any farther, their methods aren't changing anything outside the instance boundaries and their shared members (if any) are thread-safe themselves (see answer 3).
2) Yes, for pretty much the same reasons as 1.
Could a class's instance method called on a different thread use the class's properties?

Could a class's instance method called on a different thread use the class's properties?


By : user3006956
Date : March 29 2020, 07:55 AM
like below fixes the issue In the general case, you only get thread safety if you use some synchronization mechanism such as locks, or barriers, or serial queues. It's possible that a simple data value will be safe without synchronization but that's not certain either because the processor (compiler?) may decide to cache values rather than immediately write them to memory.
Objects and threads are essentially unrelated concepts. Each method executes on some thread but that has no influence on the threads where other methods execute. That includes the constructor.
Listview not updating entries when called from a different thread from inside a webserver class

Listview not updating entries when called from a different thread from inside a webserver class


By : Jon.nicholssoftware.
Date : March 29 2020, 07:55 AM
it fixes the issue You cannot directly modify the UI except from the main thread. The way to do this is to register a callback method (aka a delegate).
Here's another SO post that specifically answers how to do that, although the answer is for C#, it is the same approach for vb just a bit different syntax.
Instrumented Unit Class Test - Can't create handler inside thread that has not called Looper.prepare()

Instrumented Unit Class Test - Can't create handler inside thread that has not called Looper.prepare()


By : Md. Rahat Khan
Date : March 29 2020, 07:55 AM
this will help The error is happening because the Looper is not correctly set up for your system under test (MainActivity).
While Activity, Fragment etc. have no-args constructors, they are designed to be instantiated by the Android OS and as such calling MainActivity = new Activity() is not enough to obtain a fully-operational death star instance complete with Handler and Looper.
code :
@Rule
public ActivityTestRule<MainActivity> mActivityRule =
    new ActivityTestRule(MainActivity.class);
Related Posts Related Posts :
  • Forcefully terminating a thread I didn't write in Java
  • Issue with ojdbc jar in Maven
  • String array length java
  • Java basic compilation error
  • Inquiry about writing a Char via ByteBuffer
  • Getting unexpected results when type casting between long and double
  • Variable throws variable might not have been initialized error
  • Start/stop java application from an external script
  • Confusion in declaring String Objects
  • What are some ways to do multi-core programming on Android, not just multi-thread?
  • hibernate - process scoped identity
  • Null Pointer Exception on getGraphics()
  • Can we print a java message on console without using main method, static variable and static method?
  • sending text from editText to ListView (2 activities)
  • Transfer value from JList to another class in Java
  • Creating 2 streams with one socket
  • How measure time stolen from virtual machine, in Scala/Java?
  • How can I programmatically generate keypress events?
  • org.apache.commons.net.ssh documentation
  • Implementation of Dijkstra`s Algorithm - Stuck in an infinite loop
  • Should I throw IllegalArgmentException when 'user of given id not exist'?
  • In Nimbus, how to paint TextField when MouseOver?
  • why won't checkforWin(File f) return true when it is true?
  • Android: Cursor is always returning null even if the database is not empty
  • Repeating for loop in menu
  • Can Java garbage collector randomly delete objects in the On-Heap tier?
  • Apache CXF Exception: SSL connection unexpectedly closed
  • Add properties to ArrayList<Object> in Java
  • Multiple Adapters or One Adapter for different lists and objects - Code Performance
  • Is it good practice in Java for a class's method to redundantly return a modified global field of the class?
  • How to change the color of the background in libgdx labels?
  • direct file path not working
  • ClassFileTransformer + Javassist: no such field
  • How do I change and instance variable for an object which the user selects from a combobox?
  • reading and updating a large xml file in java
  • ActionListener and Thread.sleep
  • What is the maximum of number of arguments for varargs in java?
  • When I compile I get an error as "ask" cannot be resolved or is not a field"
  • What is the best way to check if 4 integer variables are equal to 0?
  • Storing constant webdriver elements in an enum
  • Java: Why main class does not extend Thread class
  • Java - how to find out if a directory is being used by another process?
  • How can I get a method to print?
  • Java unknown exceptions
  • BufferedReader,StreamWriter crash
  • found raw type: JComboBox
  • Java Generics -> Function return type
  • how to refresh contents of jtable on event of action listener?
  • Why does List interface extend Collection interface?
  • Pros and Cons of Clojure http client libraries
  • use final inside a for each loop
  • Convert java data object to service object
  • Unsupported major.minor version 51.0 while executing JSP
  • How do I display a word diagonally in Java?
  • making sure one task completes before another starts in java
  • My program gives an index out of bounds error
  • Removing duplicate characters in a String (user inputted keyword)
  • Jersey 2.0 Content-Length not set
  • AWS.SimpleQueueService.NonExistentQueue Exception thrown when Accessing Existing SQS queue
  • Where can I find the source code for the com.sun.jdi package?
  • shadow
    Privacy Policy - Terms - Contact Us © ourworld-yourmove.org