android - java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare(); -

i have android app running thread. want toast message show message.

when this, below exception:

logcat trace:

fatal exception: timer-0   java.lang.runtimeexception: can't create handler inside thread has not      called looper.prepare()   @ android.os.handler.<init>(handler.java:121)  @ android.widget.toast$tn.<init>(toast.java:322)  @ android.widget.toast.<init>(toast.java:91)  @ android.widget.toast.maketext(toast.java:238)  

is there work around pushing toast messages threads user interface?

i got exception because trying make toast popup background thread.
toast needs activity push user interface , threads don't have that.
1 workaround give thread link parent activity , toast that.

put code in thread want send toast message:

parent.runonuithread(new runnable() {     public void run() {         toast.maketext(parent.getbasecontext(), "hello", toast.length_long).show();     } }); 

keep link parent activity in background thread created thread. use parent variable in thread class:

private static youractivity parent; 

when create thread, pass parent activity parameter through constructor this:

public yourbackgroundthread(youractivity parent) {     this.parent = parent; } 

now background thread can push toast messages screen.