I have an Actionbar displayed on my maps fragment to which I have added a zoom-in button. When selected I would like to replace it with a zoom-out button.
When zoom-in is selected the it is obviously pases in to onOptionsItemSelected as the menu item, so it is easy to set it's attributes like this: viewZoomIn.setVisibility(viewZoomIn.GONE); My problem is, how do I get a reference to the zoom-out button on the action bar to set it as as I would like to viewZoomOut.setVisibility(viewZoomOut.VISIBLE);?
I thought I may be able to store the zoom-in and zoom-out views as instance variables and capture them when I inflate the Actionbar, like this:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
viewZoomIn = findViewById(R.id.zoom_in);
viewZoomOut = findViewById(R.id.zoom_out);
return super.onCreateOptionsMenu(menu);
This does not work.
Any help on getting hold of thes buttons, or advice on a better way of toggling my zoom-in/zoom-out buttons would be appreciated.
It probably shows, but I am pretty new to Java, so it would be preferable is any assistance were communicated in a simple manner.
Thank you.
You have to apply your visibility logic in onPrepareOptionsMenu(Menu) not in onCreateOptionsMenu(Menu) if you want to toggle MenuItem state.
private boolean currentlyZoomedIn;
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
// called the first time and after each "invalidateOptionsMenu()"
// if tha Activity is in the "zoomedIn" state, the zoomOut button will be visible
menu.findItem(R.id.zoom_in).setVisible(!currentlyZoomedIn);
menu.findItem(R.id.zoom_out).setVisible(currentlyZoomedIn);
return super.onPrepareOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()){
case R.id.zoom_in:
// do your logic when zoom_in is clicked
currentlyZoomedIn = true;
break;
case R.id.zoom_out:
// do your logic when zoom_out is clicked
currentlyZoomedIn = false;
break;
}
// force the redraw of the menu
invalidateOptionsMenu();
return super.onOptionsItemSelected(item);
}
By the way, I suggest you to use only one button and move your logic only in onOptionsItemSelected(MenuItem) to avoid an instance variable and the call to invalidateOptionsMenu() in a way like this:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// zoom_out_in_id is the id for the common button
if (item.getItemId() == R.id.zoom_out_in_id) {
// get the curren title
final CharSequence title = item.getTitle();
// if the current title is the one of zoom_in button, you have to change its infos to zoom_out ones
if (title.equals("zoom_in_title")) {
// do your logic when zoom_in is clicked
item.setIcon(R.drawable.zoom_out_icon);
item.setTitle("zoom_out_title");
} else if (title.equals("zoom_out_title")) {
// do your logic when zoom_out is clicked
item.setIcon(R.drawable.zoom_in_icon);
item.setTitle("zoom_in_title");
}
}
return super.onOptionsItemSelected(item);
}
Related
i have three menu items "enable, diable, exit". what i want to do is, when the R.id.menu_enable_bt is chosen, i want to disable it using
menu.findItem(R.id.menu_enable_bt).setVisible(false);
but i can not call
menu.findItem(R.id.menu_enable_bt).setVisible(false);
from inside the onOptionsItemSelected(..) method.
how can i change the visibility of a menu item inside onOptionsItemSelected(..)
CODE:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
Log.w(TAG, SubTag.msg("onCreateOptionsMenu"));
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu, menu);
if (this.mBTAdapter.isEnabled()) {
menu.findItem(R.id.menu_enable_bt).setVisible(false);
menu.findItem(R.id.menu_disable_bt).setVisible(true);
} else {
menu.findItem(R.id.menu_enable_bt).setVisible(true);
menu.findItem(R.id.menu_disable_bt).setVisible(false);
}
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);
Log.w(TAG, SubTag.msg("onOptionsItemSelected"));
switch (item.getItemId()) {
case R.id.menu_enable_bt:
Log.d(TAG, SubTag.bullet("onOptionsItemSelected", "menu_enable_bt"));
//menu.findItem(R.id.menu_enable_bt).setVisible(false); **how to do this**
this.mATEnableBT = new ATEnableBT();
this.mATEnableBT.execute();
break;
case R.id.menu_disable_bt:
Log.d(TAG, SubTag.bullet("onOptionsItemSelected", "menu_disable_bt"));
break;
case R.id.menu_exit:
Log.d(TAG,SubTag.bullet("onOptionsItemSelected", "menu_exit"));
finish();
break;
}
return super.onOptionsItemSelected(item);
}
you can use invalidateOptionsMenu() which will forse onCreateOptionsMenu to be called again.
From the documentation
Declare that the options menu has changed, so should be recreated. The
onCreateOptionsMenu(Menu) method will be called the next time it needs
to be displayed.
There you can check your conditions and undertake the needed actions
See the javadoc for onPrepareOptionsMenu. This is your opportunity to make changes to a menu just before it becomes visible to the user. So you should maintain some member variables describing what should be visible and use that to modify the menu items here.
I have a ListActivity (SherlockListActivity) and its content can be dynamically changed by the user. When the content changes, the options menu should be replaced.
As I learned, instead of onCreateOptionsMenu I should use onPrepareOptionsMenu that is (supposed to be) called every time the user selects the menu.
This is called right before the menu is shown, every time it is shown.
I have the following code:
#Override
public boolean onPrepareOptionsMenu(Menu menu)
{
menu.clear();
if (UserOption == UserOption1)
getSupportMenuInflater().inflate(R.menu.menu_option1, menu);
else
getSupportMenuInflater().inflate(R.menu.menu_option2, menu);
return super.onPrepareOptionsMenu(menu);
}
It is called only once during debug, so I always have the same menu.
What should I set to make it work?
Create and prepare the options menu for changing and its item selection method
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
menu.clear();
MenuInflater inflater = getMenuInflater();
if(menuString=="red"){
inflater.inflate(R.menu.red_menu, menu);
}else if(menuString=="green"){
inflater.inflate(R.menu.green_menu, menu);
}
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.new_game:
return true;
case R.id.help:
return true;
default:
return super.onOptionsItemSelected(item);
}
}
Like whenever you want to change menu call
String menuString="red or green";
invalidateOptionsMenu();
Like others told, if you want to have static menu use onCreateOptionsMenu, and if you want to change its visibility dynamically use onPrepareOptionsMenu along with onCreateOptionsMenu
I have created an action bar Search in the action bar menu.
Well, I am trying to make it go to its normal state if I click a go button or a click anywhere on the screen. Here is my code :
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
final EditText editText = (EditText) menu.findItem(
R.id.menuSearch).getActionView();
editText.addTextChangedListener(textWatcher);
menuItem = menu.findItem(R.id.menuSearch);
menuItem.setOnActionExpandListener(new MenuItem.OnActionExpandListener() {
#Override
public boolean onMenuItemActionCollapse(MenuItem item) {
menuItem.collapseActionView();
// Do something when collapsed
return true; // Return true to collapse action view
}
#Override
public boolean onMenuItemActionExpand(MenuItem item) {
//editText.clearFocus();
return true; // Return true to expand action view
}
});
return true;
}
It works well. But, It doesn't go to its normal state. I used this function
menuItem.collapseActionView();
But, no use. Thanks in advance
try this code
menuItem.collapseActionView();
inside
public boolean onOptionsItemSelected(MenuItem item) {
The framework calls onMenuItemCollapsed() to notify your code that the search view has been collapsed. A call to "menuItem.collapseActionView()" does no good in that method body. Your calls to collapseActionView() should be in the code where you want to force the view to be collapsed, such as a keystroke handler for the Go button.
I'm not trying to change the main Icon , just a menu item's icon.
The Icon is essentially displays whether I am recording at that moment. I change the icon when it's tapped using
item.setIcon(R.drawable.recordstart);
In this method.
public boolean onOptionsItemSelected(MenuItem item) {
...
} else if (item.getItemId() == R.id.ab_menu_VRecord) {
if(recording)
{
item.setIcon(R.drawable.recordstop);
}else{
item.setIcon(R.drawable.recordstart);
}
}
return true;
} else {
return super.onOptionsItemSelected(item);
}
}
Anyone know how I can do this outside this method.
Example:
class {
public MenuItem example;
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.actionbar, menu);
example = menu.findItem(R.id.ab_menu_exampleview);
return true;
}
}
Then throughout your class you can use
example.setIcon("Your Image");
Not 100% sure where you are wanting to change the icon, but you can certainly cache or create a class member variable and point it at the the MenuItem in your Activity or Fragment for example. After they click it or you inflate it, assign it to the member variable and when you need to change it, you've got a reference or "cached" pointer to it to change the icon.
I think that is a UI change so you might have to be sure that you only call that on the UI thread.
if(!item.isChecked()){
item.setChecked(true);
item.setIcon(R.drawable.icon1);
}else{
item.setChecked(false);
item.setIcon(R.drawable.icon2);
}
is this?
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);