Develop Reference

MenuItem text and icon are not being set

my application provides a list of recipes
at first all recipes are meat based and on the click of a switch in the setting page they become vegetable based
i want my app to change the titles and icons of the menu from meat based to vegetable based
i have put this code in the onPrepareOptionsMenu and it is being called but the titles are not being updated
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
super.onCreateOptionsMenu(menu);
final MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.activity_main_drawer, menu);
return true;
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
if (Build.VERSION.SDK_INT > 11) {
invalidateOptionsMenu();
MenuItem item1 = menu.findItem(R.id.nav_all);
MenuItem item2 = menu.findItem(R.id.nav_beef);
MenuItem item4 = menu.findItem(R.id.nav_chicken);
Log.d("ISVEG", MeApplication.getIsVeg().toString());
if (MeApplication.getIsVeg()) {
item1.setTitle("Omlets");
item1.setIcon(ContextCompat.getDrawable(this, R.drawable.eggs));
item2.setTitle("Broccoli");
item2.setIcon(ContextCompat.getDrawable(this, R.drawable.broccoli));
item4.setTitle("Tomato");
item4.setIcon(ContextCompat.getDrawable(this, R.drawable.tomato));
} else {
item1.setTitle("All meat");
item1.setIcon(ContextCompat.getDrawable(this, R.drawable.allmeat));
item2.setTitle("Beef");
item2.setIcon(ContextCompat.getDrawable(this, R.drawable.steak));
item4.setTitle("Chicken");
item4.setIcon(ContextCompat.getDrawable(this, R.drawable.thanksgiving));
}
}
return super.onPrepareOptionsMenu(menu);
}

Remove invalidateOptionsMenu(); from onPrepareOptionsMenu. Its not required since onPrepareOptionsMenu will prepare the Screen's standard options menu to be displayed. This is called right before the menu is shown, every time it is shown

Change the icon to Toolbar Android

How can I get an icon from the toolbar to be changed to a new one that I get with a method that is seen in a bbdd.
The problem is that I can not access the event that updates the activity to be able to change the icon.
I tried with the onPrepareOptionsMenu method, but I can not make it work.
I have not been able to do this by putting the code in onStart because it tells me that the menu object is empty or invalid.
public boolean onPrepareOptionsMenu(Menu menu) {
menu.clear();
Drawable iconoMenu = obtenerIconoMenuCarro();
getMenuInflater().inflate(R.menu.menu_categorias, menu);
menu.getItem(0).setIcon(iconoMenu);
return super.onPrepareOptionsMenu(menu);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_categorias, menu);
Drawable iconoMenu = obtenerIconoMenuCarro();
menu.getItem(0).setIcon(iconoMenu);
return true;
}
My activities are extended by AppCompactActivity and loaded through an AdapterView.
And I have the problem when I go back to the fragmentDialog or since the next activity.
Thanks.

For me the simplest way was to keep a reference to the MenuItem for later use.
Obtain when the menu item is inflated.
MenuItem menuItem;
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main_menu, menu);
//find the menu item from the id
menuItem = menu.findItem(R.id.myMenuItem);
return true;
}
Then change the image where you need to with mipmap resource or #drawable.
menuItem.setIcon(R.mipmap.ic_other_icon);

Menu Item null--->NullPointerException

I would put a number on the button that represent the numbers of notify like facebooks app.
I follow the first example in this topic :
Actionbar notification count icon (badge) like Google has
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuItem item = menu.findItem(R.id.badge);
MenuItemCompat.setActionView(item, R.layout.feed_update_count);
notifCount = (Button) MenuItemCompat.getActionView(item);
notifCount.setText(String.valueOf(SingletonGrafica.getNumeroNotifica()));
return super.onCreateOptionsMenu(menu);
}
When I call :
MenuItem item = menu.findItem(R.id.badge);
I obtain NullPointer Exception.Anyone can help me?

You need to create the menu first:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the navigation_menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.navigation_menu, menu);
return true;
}
and if you want to update the menu you should do it in:
onPrepareOptionsMenu
if you want the onPrepareOptionsMenu function to be called again you can call invalidateOptionsMenu();

You can also add item from code
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuItem item = menu.add("Badge");MenuItemCompat.setActionView(item, R.layout.feed_update_count);
return true;
}

Android: Can't toggle MenuItem icon

I'm tring to change a menuitem icon, but the icon is not being changed.
Here is how I find the MenuItem (works fine):
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu items for use in the action bar
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.activity_location_actions, menu);
mActionLocation = menu.findItem(R.id.action_location);
return super.onCreateOptionsMenu(menu);
}
Method UpdateIcon: I took a screenshot so you can see (in the red frame) that the images have been found by the system.
The mActionLocation is a MenuItem which is initialized before this Method is called and is not null.
Anyone has an idea?
UPDATE (solution by help from #vinitius)
The UpdateIcon method:
private void UpdateIcon(boolean locationOn) {
mActionLocation = locationOn; // mActionLocation is a global boolean
invalidateOptionsMenu();
}
The onPrepareOptionsMenu override:
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
// Toggle location icon
if (mActionLocation) {
menu.findItem(R.id.action_location).setIcon(R.drawable.ic_location_on_white_24dp);
} else {
menu.findItem(R.id.action_location).setIcon(R.drawable.ic_location_off_white_24dp);
}
return super.onPrepareOptionsMenu(menu);
}

You need to use onPrepareOptionsMenu(Menu menu):
This is called right before the menu is shown, every time it is shown.You can use this method to efficiently enable/disable items or otherwise dynamically modify the contents.
Inside this method, retrieve your item as you do in onCreateOtionsMenu and check whether your gps in os or not to modify your item icon.

Change menu text android

I have a string that i get from asynctask, i would like to set that string as title of menu item in actionbar.
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
this.menu = menu;
if (menu!= null) {
menu.findItem(R.id.azzera).setVisible(false);
}
MenuItem giornataItem = menu.findItem(R.id.giornata);
giornataItem.setTitle(giornataTitle);
return super.onCreateOptionsMenu(menu);
}
/* Called whenever we call invalidateOptionsMenu() */
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
// If the nav drawer is open, hide action items related to the content view
MenuItem giornataItem = menu.findItem(R.id.giornata);
giornataItem.setTitle(giornataTitle);
return super.onPrepareOptionsMenu(menu);
}
OnPrepareOptionsMenu works fine, when i change fragment or drawernav is open the title is still correct, but onCreateOptionsMenu does not set the title on application start because in that moment the string is null, because it's called before asynctask.
How can i set that string as title?

call asynctask while create menu
String tital=new Asynctask().execute("").get();
MenuItem giornataItem = menu.findItem(R.id.giornata);
giornataItem.setTitle(tital);
if you are talking about making a string to tital of your activity
then call
String tital=new Asynctask().execute("").get();
setTitle(tital);
setContentView(R.layout.MainActivity);