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I 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,