Today I managed to speed-up my Android application a lot by using a Runnable handling a piece of code inserting/updating and deleting some database stuff. However I also used RunOnUiThread() and a normal Thread() but I don't have any idea what the differences are between all three. I do know the ASyncTask, but how do you choose what to work with and what are the main differences?
An explanation / link to another site would be very nice.
Kind Regard.
Most of the code you write runs on the UI thread, ie main thread, by default. Some operations about Views must be executed on the UI thread. And operations which consume lots of resources should be executed off the UI thread.
You can start a new Thread by calling new Thread(Runnable).start(), then the task will be executed on a non-UI thread. But it's recommended to use a thread pool like ExecutorService to do this, because it reuses the threads.
For an AsyncTask, the code in doInBackground() runs on a non-UI thread from a static thread pool of AsycTask, while onPostExecuted() are executed on the UI thread. So you should do UI operations in onPostExecuted().
When using Handler, where the handleMessage() code runs is based on the Looper you pass to the constructor of Handler. By default, it's Looper.getMainLooper(), so it runs on the UI thread.