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Start your free trialAlbert Schultz
2,247 PointsI need some clarification about Looper and mHandler (t=01:37)
I've spent several hours re-watching the video, making pages of notes, trying to understand these new concepts (e.g. Message, Looper, etc), and I believe I almost got it. I have a few questions about the content in class DownloadThread.java.
Q.1) Is the mHandler
object created during initial run (when thread.start() is executed, see class MainActivity.java) even when no messages are sent (because the mDownloadButton
was not clicked)? If it was created during initial run, it would miss an argument for downloadSong
method in DownloadHandler.java.
Q.2) Can the following be confirmed: When a message is processed by the mHandle
object it will not cease to exists (i.e. not re-instantiated)?
For illustrative purposes:
Looper.prepare()
↓
mHandler // instantiated from DownloadHandler class
↓
Looper.loop()
↓
(a message arrives)
↓
mHandler // takes arbitrary data attached to message (when queryButton is clicked)
↓
downloadSong(message) // pass data attached to message as argument to method (DownloadHandler.java)
↓
Looper.loop()
↓
(a message arrives)
↓
mHandler // takes arbitrary data attached to message (when queryButton is clicked)
↓
downloadSong(message) // pass data attached to message as argument to method (DownloadHandler.java)
Thanks in advance,