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Changing the actionbar menu state depending on fragment

I am trying to show/hide items in my action bar depending on which fragment is visible.
In my MainActivity I have the following
/* Called whenever invalidateOptionsMenu() is called */
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
if(this.myFragment.isVisible()){
menu.findItem(R.id.action_read).setVisible(true);
}else{
menu.findItem(R.id.action_read).setVisible(false);
}
return super.onPrepareOptionsMenu(menu);
}
This works great however, when the device is rotated there is a issue. After the rotation is complete onPrepareOptionsMenu is called again however this time this.myFragment.isVisible() returns false...and hence the menu item is hidden when clearly the fragment is visible (as far as whats shown on the screen).

Based on the Fragments API Guide, we can add items to the action bar on a per-Fragment basis with the following steps:
Create a res/menu/fooFragmentMenu.xml that contains menu items as you normally would for the standard menu.
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:id="#+id/newAction"
android:orderInCategory="1"
android:showAsAction="always"
android:title="#string/newActionTitle"
android:icon="#drawable/newActionIcon"/>
</menu>
Toward the top of FooFragment's onCreate method, indicate that it has its own menu items to add.
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
...
}
Override onCreateOptionsMenu, where you'll inflate the fragment's menu and attach it to your standard menu.
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.fooFragmentMenu, menu);
super.onCreateOptionsMenu(menu, inflater);
}
Override onOptionItemSelected in your fragment, which only gets called when this same method of the host Activity/FragmentActivity sees that it doesn't have a case for the selection.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.newAction:
...
break;
}
return super.onOptionsItemSelected(item);
}

Try using Fragment's setRetainInstance(true); when your fragment is attached to the Activity. That way your fragment will retain it's current values and call the lifecycle when device rotated.

Edit: This is a quick and dirty fix, see es0329's answer below for a better solution.
Try adding this attribute to your activity tag in your android manifest:
android:configChanges="orientation|screenSize"

Why do I get copies of the same option menu item in ActionBar?

I use ActionbarSherlock together with Fragments. In one of the Fragments I add an option menu item in the Actionbar. It shows up and when I click it I get a callback in which I move to another Activity. When I return to this Activity I get another copy of the same option menu item in the Actionbar. I know have two option that I can press. Both works.
How do I get rid of the extra menu item?
The menu looks like this:
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:id="#+id/menu_scan_book"
android:orderInCategory="100"
android:showAsAction="ifRoom"
android:title="#string/menu_scan_book"/>
</menu>
In my SherlockFragment I have this code
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
inflater.inflate(R.menu.scan_book_action_menu, menu);
}
In the SherlockFragmentActivity owning the Fragment I have tried to call
supportInvalidateOptionsMenu()
when I return from the Activity I moved to above.
What am I missing?

Did you try to call menu.clear() in public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) ? It's just a workaround but it worked for me.
Go here for more informations : Fragments, with the same menu, on the same layout cause duplicated menuitem

Android - Populate menu upon activity onCreate

Perhaps I'm missing the obvious, but my menu is only been created and populated when onCreateOptionsMenu(Menu menu) is called, as in this example, and this only seem to be called after I press the menu button.
I would like to populate the menu upon the creation of the activity, how can achieve that?
UPDATE:
Perhaps a better question would be:
How can I get the Menu instance of my Activity?
Thanks

Create a class which holds those states then set your enabled/checked etc from the properties of that class in onCreateOptionsMenu()
class MenuStates{
public static boolean userDidPressTheButton;
public static boolean serverDidRespond;
public static boolean colorWasChanged;
}
void someEventHandler(){
MenuStates.userDidPressTheButton = true;
}
void onCreateOptionsMenu(){
myCheckBox.setChecked(MenuStates.userDidPressTheButton);
}
[EDIT]
You don't say why you want to get the menu instance. One approach:
Menu optsMenu;
...
// this is called once only before the end of the Activity onCreate().
onCreateOptionsMenu(Menu menu){
opstMenu = menu;
super.onCreateOptionsMenu(menu);
}
Following that, modify your menu as you wish. Do any "as it pops" up work in onPrepareOptionsMenu().
The key understanding is the difference between onCreateOptionsMenu() and onPrepareOptionsMenu().
[MORE EDIT]
To completely control the thing yourself:
Menu optsMenu;
onCreate(){
openOptionsMenu() // the menu won't show in onCreate but onCreateOptionsMenu is shown
closeOptionsMenu()
}
onCreateOptionsMenu(Menu menu){
optsMenu = menu;
}
onPrepareOptionsMenu(Menu menu){
menu.clear();
for (int i=0;ioptsMenu.size();i++){
menu.add(optsMenu.get(i).getTitle());
}
return super.onPrepareOptionsMenu(menu);
}
From the docs
You can safely hold on to menu (and any items created from it), making modifications to it as desired, until the next time onCreateOptionsMenu() is called.
http://developer.android.com/reference/android/app/Activity.html#onCreateOptionsMenu%28android.view.Menu%29

How can I get the options menu of my Activity?

In some methods of my Activity I want to check the title of menu or know if it is checked or not. How can I get Activity's menu. I need something like this.getMenu()

Be wary of invalidateOptionsMenu(). It recreates the entire menu. This has a lot of overhead and will reset embedded components like the SearchView. It took me quite a while to track down why my SearchView would "randomly" close.
I ended up capturing the menu as posted by Dark and then call onPrepareOptionsMenu(Menu) as necessary. This met my requirement without an nasty side effects. Gotcha: Make sure to do a null check in case you call onPrepareOptionsMenu() before the menu is created. I did this as below:
private Menu mOptionsMenu;
#Override
public boolean onCreateOptionsMenu(final Menu menu) {
mOptionsMenu = menu
...
}
private void updateOptionsMenu() {
if (mOptionsMenu != null) {
onPrepareOptionsMenu(mOptionsMenu);
}
}

Call invalidateOptionsMenu() instead of passing menu object around.

you could do it by passing the Menu object to your Activity class
public class MainActivity extends Activity
{
...
...
private Menu _menu = null;
#Override
public boolean onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
_menu = menu;
return true;
}
private Menu getMenu()
{
//use it like this
return _menu;
}
}

There several callback methods that provide menu as a parameter.
You might wanna manipulate it there.
For example:
onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo)
onCreateOptionsMenu(Menu menu)
onCreatePanelMenu(int featureId, Menu menu)
There several more, best you take a look in activity documentation and look for your desired method:
http://developer.android.com/reference/android/app/Activity.html

As far as I could understand what you want here is which may help you:
1. Refer this tutorial over option menu.
2. Every time user presses menu button you can check it's title thru getTitle().
3. Or if you want to know the last menu item checked or selected when user has not pressed the menu button then you need to store the preferences when user presses.

Android now has the Toolbar widget which was a Menu you can set/get. Set the Toolbar in your Activity with some variation of setSupportActionBar(Toolbar) for stuff like onCreateOptionsMenu from a Fragment for example. Thread revived!

Re-using Options menu code

Is there a convenient way of showing the same Options menu options in multiple Activities?
Example: In my app, I display a TV Guide in one of three ways.
Seven day guide (TabActivity with 7 tabs)
All channels 'Now showing' (ListActivity)
All shows today by start time (Activity - could be changed easily to ListActivity)
For the Options menu in the TabActivity, the code is quite simple...
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
menu.clear();
inflater.inflate(R.menu.gv_options_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.view:
...
...
}
}
...but at the moment it seems I need to copy/paste it to the other two Activities which I don't like doing. If I change the Options menu code for one I'll need to do it for the other two also.
The only alternative I can think of is I have a 'helper' class (POJO) to which I could add a method and pass the context into to allow use of the getMenuInflator() method and another method I could pass the result of item.getItemId() into to process with the switch-case.
What is the normal way of having multiple Activities with the same Options menu?

Create a simple separate class with these two methods:
public class MyMenuHandler {
private Activity mActivity;
public MyMenuHandler(Activity activity) {
mActivity = activity;
}
public boolean onPrepareOptionsMenu(Menu menu) {
MenuInflater inflater = mActivity.getMenuInflater();
menu.clear();
inflater.inflate(R.menu.gv_options_menu, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.view:
...
}
}
}
In your activities override those callback methods and redirect the call to an instance of your MyMenuHandler class:
public class MyActivity1 extends TabActivity {
private MyMenuHandler mMenuHandler;
#Override
public void onCreate(Bundle savedInstanceState) {
...
mMenuHandler = new MyMenuHandler(this);
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
// you may also add here some items which are specific
// for one activity, not for the others
...
return mMenuHandler.onPrepareOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// handle selection of your specific items here,
// if none of them has been selected call mMenuHandler method
...
return mMenuHandler.onOptionsItemSelected(item);
}
}
This will let you hold in one place the code which respond to selection of your basic menu items, so there will be no need to worry about copy-pasting it to all activities which are to have the same menu.

One approach is to use inheritance with your Activities. Create a base Activity that implements the options menu methods and then each child Activity will gain that functionality. This is the recommended approach on the Android developer site:
Tip: If your application contains multiple activities and some of them provide the same Options Menu, consider creating an activity that implements nothing except the onCreateOptionsMenu() and onOptionsItemSelected() methods. Then extend this class for each activity that should share the same Options Menu. This way, you have to manage only one set of code for handling menu actions and each descendant class inherits the menu behaviors.
Unfortunately this won't work for you as you are not inheriting from Activity itself but differing subclasses of it, but that is the 'normal' way to do it.

You can encapsulate your action menu in a fragment. In this way you only need to add the fragment in the onCreate menu of your activity.
You need to call setHasOptionsMenu once the fragment is created.
To add the add fragment use a tag instead of a layout id.