I’m currently trying to adapt my application to use the “Compatibility Libraries for Android v4” to provide the benefits of the usage of fragments even to Android 1.6 users.
The implementation of a context menu seems to be tricky:
- The main activity of the application
is extending the FragmentActivity
class. - The fragments are all based on one
class which extends the Fragment class. - The fragment class is calling
registerForContextMenu() in its onCreateView() method and overrides the methods
onCreateContextMenu() and onContextItemSelected().
For onCreateContextMenu() this works pretty well. The context menu is inflated from a resource file and slightly modified based on the selected item (which is based on a listView… even if the fragment is not an ListFragment).
The problem occurs when a context menu entry is selected.
onContextItemSelected() is called for all currently existing fragments starting with the first added one.
In my case the fragments are used to show the content of a folder structure. When the context menu of a subfolder fragment is opened and a menu item is selected, onContextItemSelected() is first called on the upper levels (depending on how many fragments are allowed/visible in this moment).
Right now, I use a workaround by a field on activity level which holds the tag of last fragment calling its onCreateContextMenu(). This way I can call “return super.onContextItemSelected(item)” in the begin of onContextItemSelected() when the stored tag is not the same as getTag().
But this approach looks a bit dirty to me.
Why is onContextItemSelected() called on all fragments? and not just one the one that was calling onCreateContextMenu()?
What is the most elegant way to handle this?
I found an alternative. It does not change anything on my problem above, but it makes it pointless.
I have remove the context menu completely from my application. Instead I capture the longclick on a list item and change the visible buttons of the action bar in this moment.
From the user point of view this is much more tablet like as a context menu.
In backward compatible applications the actionbar does not exist. So I’ve decided to build my own (kind of toolbar on top) for the devices pre Honeycomb.
If you would like to stay with the context menu, I did not find a better solution as the workaround I’ve mentioned above.