Question

I have destroyed my activity by calling finish().But the thread in the activity is still running after destroying the activity and it causes application crash..
How can I handle this?Why the thread runs after destroying the activity?
Please provide some help?

class DBThread extends Thread {

    @Override
    public void run() {
        while (finish) {
            Cursor cursor = null;

            Cursor mCursor = lrDB.selectUserDetails(mUser_Id);
            if (mCursor.getCount() > 0) {
                mCursor.moveToNext();
                String Name = mCursor .getString(0);
                String userName = mCursor .getInt(1);
                String password = mCursor .getString(3);

            }
            mCursor.close();

        }
    }
}

Answer 1

First correct your thread:

class DBThread extends Thread { 
    @Override 
    public void run() { 
        while (!isInterrupted()) {
            Cursor mCursor = lrDB.selectUserDetails(mUser_Id); 
            if (mCursor.getCount() > 0) { 
                mCursor.moveToNext(); 
                String Name = mCursor .getString(0); 
                String userName = mCursor .getInt(1); 
                String password = mCursor .getString(3); 

            } 
            mCursor.close(); 
        } 
    } 
} 

Secondly to close thread gracefuly do something like that in activity:

@Override
public void onDestroy() {
    if (yourThread!=null) {
        yourThread.interrupt(); // request to terminate thread in regular way
        yourThread.join(500); // wait until thread ends or timeout after 0.5 second
        if (yourThread.isAlive()) {
            // this is needed only when something is wrong with thread, for example hangs in ininitive loop or waits to long for lock to be released by other thread.
            Log.e(TAG, "Serious problem with thread!");
            yourThread.stop();
        }
    }
    super.onDrestroy();
}

Note that Thread.destroy() is deprecated and will not work.