Android: Showing Action Bar menu items depending on ViewPager

Question

I am having trouble getting the following piece of code to work out. I have a viewpager with 3 fragments, and I want a search icon to only show up on one. I s

Answer 1

You can implement onCreateOptionsMenu() in your Fragment and set 'setHasOptionsMenu(true)' for the fragment

Answer 2

a possible solution for this problem would be inflating your custom menu inside the activity hosts your ViewPager and getting a menu reference as below:

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
     getMenuInflater().inflate(R.menu.custom_menu, menu);
     customMenu = menu;
     return super.onCreateOptionsMenu(menu);
 }

after that you can easily hide/show the menu's items without any delay inside onPageSelected method as below:

 @Override
 public void onPageSelected(int position) {
  switch (position) {
        case 0: { 
           customMenu.getItem(0).setVisible(false);
           break;
        }
       case 1: { 
           customMenu.getItem(0).setVisible(true);
             break;
        }
     }

Answer 3

invalidateOptionsMenu make the system calls the method onPrepareOptionsMenu, so you can override this method as follows:

public boolean onPrepareOptionsMenu(Menu menu) {
      int pageNum = getCurrentPage();
      if (pageNum == 1) {
         menu.findItem(R.id.menu_search).setVisible(true);

      }
      else {
         menu.findItem(R.id.menu_search).setVisible(false);
      }
   }

public void onPageSelected(int pageNum) {
    invalidateOptionsMenu();
}

Answer 4

I used Nermeen's answer and managed to get it without any delay.

I don't inflate anything in onCreateOptionsMenu, but use it to get a reference to the menu:

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
     customMenu = menu;
     return super.onCreateOptionsMenu(menu);
 }

Then, in onPrepareOptionsMenu(), I call the viewpager getCurrentItem() (should be something like viewPager.getCurrentItem()), call invalidateOptionsMenu() and inflate whatever menu I want in that page using the customMenu reference I created in onCreateOptionsMenu().