Android: Can't toggle MenuItem icon - android

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.

Related

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;
}

How can I add MenuItem in Android after onCreateOptionsMenu()

I've met a serious problem. I want to add the MenuItem after the user successfully logged in.
At the beginning I use the following method to make it available.
The following code doesn't work now , I mentioned it as to illustrate my idea.
Private Menu mymenu;
public boolean onCreateOptionsMenu(Menu menu) {
// TODO Auto-generated method stub
super.onCreateOptionsMenu(menu);
mymenu=menu;
return super.onCreateOptionsMenu(menu);
}
public void process(){
MenuInflater inflater=this.getMenuInflater();
inflater.inflate(R.menu.my_menu,mymenu);
}
It seems this idea worked as I remembered.But after doing something I couldn't remember , It doesn't work!
After the debug , I find it's because mymenu=null .
I guessed there is a way to set mymenu=menu
Can anyone help?
The problem you could be having with that code is calling the super twice.
To do what you want, you could override onPrepareOptionMenu and set the visibility to hidden on all menu items you don't want until your state is such that you want to "add" it.
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
MenuItem menuItem = menu.findItem(R.id.<id of menuitem>);
menuItem.setVisible(<condition>);
return true;
}
and just use standard code in onCreateOptionsMenu:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.<id of menu with all items you'll need>, menu);
return true;
}
There is a method, onPrepareOptionsMenu(Menu menu) method which you could override and dynamically change the menus.

Android - Enabling MenuItems by code

I need to enable a MenuItem when a previous screen (Activity) returns.
I tried this code:
...
((MenuItem)findViewById(R.id.menu_how)).setEnabled(true);
...
but a null pointer exception is launched.
BTW, the menu_how is set to false in xml; and the code is part of onActivityResult(int requestCode, int resultCode, Intent data) call.
Try using menu.findItem(R.id.menu_how) in onCreateOptionsMenu and save a reference for later use.
This should work fine with enabled, however, I've found that setting a menu item to invisible in the XML means you can't show/hide it programmatically.
I found something at the android dev site that might be helpful (look for the section "Changing menu items at runtime")
It said that the onCreateOptionsMenu() method fired only when the the menu for the activity is created, and it happens when this activity starts. So if you want to change the menu items after the menu/activity was created, you need to override the onPrepareOptionsMenu() method instead. search the link for full details.
EDIT:
Just made it and it's working fine. I'm using one boolean var per menuItem which represents if this item should be enabled or not. This is my code:
/*************************************Game Menu**************************************/
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.game_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId())
{
case R.id.gm_new_game:
//newGame();
return true;
case R.id.gm_stand_up:
//some code when "gm_stand_up" button clicked..
return true;
case R.id.gm_forfeit:
//some code when "gm_forfeit" button clicked..
return true;
case R.id.gm_surrender:
//some code when "gm_surrender" button clicked..
return true;
case R.id.gm_exit_table:
exitTableCommand();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
public boolean onPrepareOptionsMenu(Menu menu)
{
menu.findItem(R.id.gm_forfeit).setEnabled(forfeitMenuButtonIsEnabled);
menu.findItem(R.id.gm_surrender).setEnabled(surrenderMenuButtonIsEnabled);
menu.findItem(R.id.gm_new_game).setEnabled(newGameMenuButtonIsEnabled);
menu.findItem(R.id.gm_stand_up).setEnabled(standUpMenuButtonIsEnabled);
return super.onPrepareOptionsMenu(menu);
}
where are you calling this? (Sorry, didn't read carefully) I think you need to call it after the menu is inflated (usually in OnCreateOptionsMenu). To do this, you can set a variable to true when the other Activity returns, then do ((MenuItem)findViewById(R.id.menu_how)).setEnabled(mMyBooleanField) in OnCreateOptionsMenu after the call to inflater.inflate.
Edit: To accomplish this in code, it might look something like this:
At the top of the class (along with all the other class members):
Boolean mEnableMenuItem = false;
In OnCreateOptionsMenu:
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.options_main, menu);
((MenuItem)findViewById(R.id.menu_how)).setEnabled(mEnableMenuItem );
In OnActivityResult:
mEnableMenuItem = true;
Keep a reference to Menu in your activity:
private Menu mMenu;
Then:
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_note, menu);
mMenu = menu;
return true;
}
Now, to access menu items anywhere in your activity use similar code to this:
mMenu.findItem(R.id.menu_how).setVisible(false);
or
mMenu.findItem(R.id.menu_how).setEnabled(true);

How to make a dynamic options menu?

The problem is that the following method gets called one time when the Menu button is pressed:
public boolean onCreateOptionsMenu(Menu menu)
How can I recreate the menu at a later time in order to change some options, disable some options, etc?
Override this
onPrepareOptionsMenu(Menu menu)
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
MenuItem item = menu.findItem(R.id.refresh);
if (item != null) {
item.setVisible (shouldIShowThisItem)
}
}
invalidateOptionsMenu();
if you want to push the menu changes use this.

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