How to change the menu bar item by oncreate() method

How to change the menu bar item by oncreate() method - android

In here I am having list of colleges. I favourite the particular college by using menu bar Favourite_icon.Then the Favourite_icon changed as Favourite_icon1 When the college is viewed by some other time that menu bar Favourite_icon should as Favourite_icon1. So that I am checking Whether the college is already favourited by using server API. So how can I set the menu bar Icon from oncreate() method.

If you mean the Android menu bar, you shouldn't try and change it in onCreate(), because it hasn't been instantiated, and will always throw a NullPointerException.
If you are waiting for an API response to find the favorites, you will need to create a local menu variable to access it.
Menu myMenu;
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
myMenu = menu;
return super.onPrepareOptionsMenu(menu);
}
Then, whatever your server API's callback method should do something like this:
void callback(boolean favorite) {
if (favorite) {
myMenu.findItem(R.id.myMenuItem).setIcon(R.drawable.Favourite_icon1);
}
}

Something like this:
#Override
protected void onCreate (Bundle savedInstanceState){
...
isSomethingInMenu = true;
invalidateOptionsMenu();
...
}
#Override
public boolean onCreateOptionsMenu (Menu menu){
getMenuInflater().inflate(R.menu.menu, menu);
menu.findItem(R.id.action_something).setVisible(isSomethingInMenu);
...
}

Related

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.

Input for onPrepareOptionsMenu

I'm trying to make an app that disables the user from going to the menu. I know I have to override onPrepareOptionsMenu(Menu menu) but what do I have to put as input for menu if I want to use this function in a different function? I don't quite understand the Menu object and how many types it has.

Do something like this:
private Menu mOptionsMenu;
#Override
public boolean onCreateOptionsMenu(final Menu menu) {
mOptionsMenu = menu
...
}
private void updateOptionsMenu() {
if (mOptionsMenu != null) {
onPrepareOptionsMenu(mOptionsMenu);
}
}
and then call the updateOptionsMenu() function where you want

Android: Change menu item from Log in to Log out

My menu has a item to Log in, but when you are logged in I want it to say Log out.
How?
If I'm going to change the item after its created, its probably through this method
#Override
public boolean onCreateOptionsMenu( Menu menu ) {
MenuInflater inflater = getMenuInflater();
inflater.inflate( R.menu.menu_main, menu );
return true;
}
Afaik the onCreateOptionsMenu() happens after the onCreate so putting any getItemId() for the menu there will give me a NullPointerException right away.
I want the app to find out if its supposed to use the string R.string.Logout if its logged in.
I dont even know what to search for for this issue. All I found was how to make a string implement names, like this answer https://stackoverflow.com/a/7646689/3064486

You should use onPrepareOptionsMenu(Menu menu) instead to update menu items
#Override
public boolean onPrepareOptionsMenu(Menu menu){
super.onPrepareOptionsMenu(menu);
MenuItem someMenuItem = menu.findItem(R.id.some_menu_item);
someMenuItem.setTitle("Log out");
return super.onPrepareOptionsMenu(menu);
}
To refresh Menu items call invalidateOptionsMenu();from Activity
From Android API guides: "If you want to modify the options menu based on events that occur during the activity lifecycle, you can do so in the onPrepareOptionsMenu() method. This method passes you the Menu object as it currently exists so you can modify it, such as add, remove, or disable items. (Fragments also provide an onPrepareOptionsMenu() callback.)"

After you inflate a menu, you can customize its items. To get each one, you must call findItem() with the item's id. In particular, you can use setTitle() to change the displayed string.
For example:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
if (mIsLoggedIn)
menu.findItem(R.id.action_login).setTitle("Log out");
return true;
}
where action_login is the id you set for this particular menu item in the menu's xml file.

private void updateUI() {
runOnUiThread(new Runnable() {
#Override
public void run() {
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
Menu menu = navigationView.getMenu();
MenuItem nav_signin = menu.findItem(R.id.nav_signin);
nav_signin.setTitle(MyApp.signedIn ? "Sign out" : "Sign in");
}
});
}

Google Glass : OnCreateOptionsMenu

I am trying to modify the title of menu item on google glass dynamically.
As there is no hardware menu button and My activity is themed NoActionBarFullScreen,
creating and initializing the Menu menu item in onCreateOptionsMenu always give null value because onCreateOptionsMenu never called. So how to do that ?
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.gatt_services, menu);
if (!init) {
// I want to do this outside of this function also
menu.findItem(R.id.menu_connect).setTitle("Connect"); }
else {
menu.findItem(R.id.menu_connect).setTitle("Disconnect");
}
// so I initialized this variable here
this.menu = menu; // but this is always null
return true;
}
MenuItem connetItem = menu.findItem(R.id.menu_connect); // App crashes
So how do i access this menu item and change its title?

Hide/Show Action Bar Option Menu Item for different fragments

I have a Sherlock Fragment Activity in which there are 3 Fragments.
Fragment A, Fragment B, Fragment C are three fragments. I want to show a done option menu in Fragment B only.
And the activity is started with Fragment A. When Fragment B is selected done button is added.
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
if(!menusInflated){
inflater.inflate(R.menu.security, menu);
menusInflated=true;
}
super.onCreateOptionsMenu(menu, inflater);
}
When I again start Fragment A I want to options Menu DONE (which was set at Fragment B) for this I am doing like this
setHasOptionsMenu(false);
MenuItem item = (MenuItem) menu.findItem(R.id.done_item);
item.setVisible(false);
But this is not hiding at all, also it is giving NullPointerException when Activity if first started with Fragment A.
Please let me know what is the problem.

Try this...
You don't need to override onCreateOptionsMenu() in your Fragment class again. Menu items visibility can be changed by overriding onPrepareOptionsMenu() method available in Fragment class.
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public void onPrepareOptionsMenu(Menu menu) {
menu.findItem(R.id.action_search).setVisible(false);
super.onPrepareOptionsMenu(menu);
}

This is one way of doing this:
add a "group" to your menu:
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<group
android:id="#+id/main_menu_group">
<item android:id="#+id/done_item"
android:title="..."
android:icon="..."
android:showAsAction="..."/>
</group>
</menu>
then, add a
Menu menu;
variable to your activity and set it in your override of onCreateOptionsMenu:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
this.menu = menu;
// inflate your menu here
}
After, add and use this function to your activity when you'd like to show/hide the menu:
public void showOverflowMenu(boolean showMenu){
if(menu == null)
return;
menu.setGroupVisible(R.id.main_menu_group, showMenu);
}
I am not saying this is the best/only way, but it works well for me.

To show action items (action buttons) in the ActionBar of fragments where they are only needed, do this:
Lets say you want the save button to only show in the fragment where you accept input for items and not in the Fragment where you view a list of items, add this to the OnCreateOptionsMenu method of the Fragment where you view the items:
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
if (menu != null) {
menu.findItem(R.id.action_save_item).setVisible(false);
}
}
NOTE: For this to work, you need the onCreate() method in your Fragment (where you want to hide item button, the item view fragment in our example) and add setHasOptionsMenu(true) like this:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
Might not be the best option, but it works and it's simple.

This will work for sure I guess...
// Declare
Menu menu;
MenuItem menuDoneItem;
// Then in your onCreateOptionMenu() method write the following...
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
this.menu=menu;
inflater.inflate(R.menu.secutity, menu);
}
// In your onOptionItemSelected() method write the following...
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.done_item:
this.menuDoneItem=item;
someOperation();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
// Now Making invisible any menu item...
public void menuInvisible(){
setHasOptionsMenu(true);// Take part in populating the action bar menu
menuDoneItem=(MenuItem)menu.findItem(R.id.done_item);
menuRefresh.setVisible(false); // make true to make the menu item visible.
}
//Use the above method whenever you need to make your menu item visible or invisiable
You can also refer this link for more details, it is a very useful one.

MenuItem Import = menu.findItem(R.id.Import);
Import.setVisible(false)

Try this
#Override
public boolean onCreateOptionsMenu(Menu menu){
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.custom_actionbar, menu);
menu.setGroupVisible(...);
}

By setting the Visibility of all items in Menu, the appbar menu or overflow menu will be Hide automatically
Example
private Menu menu_change_language;
...
...
#Override
public boolean onCreateOptionsMenu(Menu menu) {
...
...
menu_change_language = menu;
menu_change_language.findItem(R.id.menu_change_language).setVisible(true);
return super.onCreateOptionsMenu(menu);
}
Before going to other fragment use bellow code:
if(menu_change_language != null){
menu_change_language.findItem(R.id.menu_change_language)
.setVisible(false);
}

Hello I got the best solution of this, suppose if u have to hide a particular item at on create Menu method and show that item in other fragment. I am taking an example of two menu item one is edit and other is delete. e.g menu xml is as given below:
sell_menu.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/action_edit"
android:icon="#drawable/ic_edit_white_shadow_24dp"
app:showAsAction="always"
android:title="Edit" />
<item
android:id="#+id/action_delete"
android:icon="#drawable/ic_delete_white_shadow_24dp"
app:showAsAction="always"
android:title="Delete" />
Now Override the two method in your activity & make a field variable mMenu as:
private Menu mMenu; // field variable
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.sell_menu, menu);
this.mMenu = menu;
menu.findItem(R.id.action_delete).setVisible(false);
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.action_delete) {
// do action
return true;
} else if (item.getItemId() == R.id.action_edit) {
// do action
return true;
}
return super.onOptionsItemSelected(item);
}
Make two following method in your Activity & call them from fragment to hide and show your menu item. These method are as:
public void showDeleteImageOption(boolean status) {
if (menu != null) {
menu.findItem(R.id.action_delete).setVisible(status);
}
}
public void showEditImageOption(boolean status) {
if (menu != null) {
menu.findItem(R.id.action_edit).setVisible(status);
}
}
That's Solve from my side,I think this explanation will help you.

You can make a menu for each fragment, and a global variable that mark which fragment is in use now.
and check the value of the variable in onCreateOptionsMenu and inflate the correct menu
#Override
public boolean onCreateOptionsMenu(Menu menu) {
if (fragment_it == 6) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.custom_actionbar, menu);
}
}

Okay I spend couple of hour to get this solution.apparently you can get menuitem from your toolbar to anywhere in activity or fragment. So in my case.
var menuItem = toolbar.menu;
Now to get specfic item from menu item
favIcon = menuItem.findItem(R.id.favourite);
Note: favIcon is MenuItem declare global
Now if you can do whatever you want to do for this icon
eg. to make it invisible
favIcon?.isVisible=false

Even though the question is old and answered. There is a simpler answer to that than the above mentioned. You don't need to use any other variables.
You can create the buttons on action bar whatever the fragment you want, instead of doing the visibility stuff(show/hide).
Add the following in the fragment whatever u need the menu item.
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu, menu);
super.onCreateOptionsMenu(menu, inflater);
}
Sample menu.xml file:
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:id="#+id/action_addFlat"
android:icon="#drawable/add"
android:showAsAction="ifRoom|withText"
android:title="#string/action_addFlat"/>
</menu>
Handling onclick events is as usual.

Late to the party but the answers above didn't seem to work for me.
My first tab fragment (uses getChildFragmentManager() for inner tabs) has the menu to show a search icon and uses android.support.v7.widget.SearchView to search within the inner tab fragment but navigating to other tabs (which also have inner tabs using getChildFragmentManager()) would not remove the search icon (as not required) and therefore still accessible with no function, maybe as I am using the below (ie outer main tabs with each inner tabs)
getChildFragmentManager();
However I use the below in my fragments containing/using the getChildFragmentManager() for inner tabs.
//region onCreate
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRetainInstance(true);
//access setHasOptionsMenu()
setHasOptionsMenu(true);
}
//endregion onCreate
and then clear the menu item inside onPrepareOptionsMenu for fragments(search icon & functions)
#Override
public void onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
//clear the menu/hide the icon & disable the search access/function ...
//this will clear the menu entirely, so rewrite/draw the menu items after if needed
menu.clear();
}
Works well and navigating back to the tab/inner tab with the search icon functions re displays the search icon & functions.
Hope this helps...

For some reason the method was not working for me this is how I solved it according to the accepted solution
//This should be in on create
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
showOverflowMenu(false);
}
},100);
#Override
public boolean onCreateOptionsMenu(Menu menu) {
this.menu = menu;
getMenuInflater().inflate(R.menu.options_menu, menu);
return true;
}
public void showOverflowMenu(boolean showMenu){
if(menu == null)
return;
menu.setGroupVisible(R.id.grp, showMenu);
}

Develop Reference

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How to change the menu bar item by oncreate() method - android

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Android: Can't toggle MenuItem icon

Input for onPrepareOptionsMenu

Android: Change menu item from Log in to Log out

Google Glass : OnCreateOptionsMenu

Hide/Show Action Bar Option Menu Item for different fragments

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