Android adding a submenu to a menuItem, where is a

问题:

I want to add a submenu inside my OptionsMenu to a menuItem, programatically according to my parameters. I've checked "MenuItem" in android sdk and there is no addSubMenu() method!, although you can find "hasSubMenu()" and "getSubMenu".

Was thinking on doing this in onCreateOptionsMenu:

public boolean onCreateOptionsMenu(Menu menu) {

    MenuItem mi = menu.getItem(MYITEMID);  // << this is defined in my XML optionsMenu
    SubMenu subm = mi.addSubMenu(0,1,0,"Map 1"); // no addSubMenu() method!!!???
....

How do I create a submenu inside a menuitem in code?

回答1:

Sometimes Android weirdness is really amazing (and amusing..). I solved it this way:

a) Define in XML a submenu placeholder like this:

<item android:visible="true" android:id="@+id/m_area"
   android:titleCondensed="Areas"
   android:title="Areas"
   android:icon="@drawable/restaur"
   android:enabled="true"> 
   <menu>
    <item android:id="@+id/item1" android:title="Placeholder"></item>
   </menu>
</item>

b) Get sub menu item in OnCreateOptionsMenu, clear it and add my submenu items, like this:

    public boolean onCreateOptionsMenu(Menu menu) { 
            MenuInflater inflater = getMenuInflater();
            inflater.inflate(R.menu.mapoptions, menu);

            int idx=0;
            subm = menu.getItem(MYITEM_INDEX).getSubMenu(); // get my MenuItem with placeholder submenu
            subm.clear(); // delete place holder

            while(true)
            {
                anarea = m_areas.GetArea(idx); // get a new area, return null if no more areas
                if(anarea == null)
                    break;
                subm.add(0, SUBAREASID+idx, idx, anarea.GetName()); // id is idx+ my constant
                ++idx;
            }
}

回答2:

I know this is an old question, but I just came across this problem myself. The most straightforward way of doing this, seems to be to simply specify the item itself as a submenu, then add to this item. E.g.:

menu.add(groupId, MENU_VIEW, Menu.NONE, getText(R.string.menu_view));
menu.add(groupId, MENU_EDIT, Menu.NONE, getText(R.string.menu_edit));
SubMenu sub=menu.addSubMenu(groupId, MENU_SORT, Menu.NONE, getText(R.string.menu_sort));
sub.add(groupId, MENU_SORT_BY_NAME, Menu.NONE, getText(R.string.menu_sort_by_name));
sub.add(groupId, MENU_SORT_BY_ADDRESS, Menu.NONE, getText(R.string.menu_sort_by_address));
:
:

回答3:

Here's a complete answer which builds on the idea of using a placeholder but uses mostly xml to add the submenu.

If you have a menu like so called main_menu.xml:

<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:title="My Menu"
    android:id="@+id/my_menu_item">
    <!-- A empty SubMenu -->
    <menu></menu>
</item>
</menu>

Create another menu sub_menu.xml which will be used in my_menu_item:

<menu xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:title="SubMenu One"
    android:id="@+id/submenu_one" />
  <item android:title="SubMenu Two"
    android:id="@+id/submenu_two" />
  <item android:title="SubMenu Three"
    android:id="@+id/submenu_three" />
</menu>

In your onCreateOptionsMenu:

public boolean onCreateOptionsMenu(Menu menu) {
   // Inflate your main_menu into the menu
   getMenuInflater().inflate(R.menu.main_menu, menu);

   // Find the menuItem to add your SubMenu
   MenuItem myMenuItem = menu.findItem(R.id.my_menu_item);

   // Inflating the sub_menu menu this way, will add its menu items 
   // to the empty SubMenu you created in the xml
   getMenuInflater().inflate(R.menu.sub_menu, myMenuItem.getSubMenu());

}

This solution is nice since the inflater handles most of the work.

回答4:

The best way to do this is in your xml menu file. You can do this by creating a new menu object inside of an item:

<menu>
  <item>
    ...
    <menu>
      ...
    </menu>
    ...
  </item>
</menu>

回答5:

To provide a comprehensive example of Phil's answer, here is my complete, working XML for a menu with two choices, each of which is a menu with three choices. I intend to add a third menu to the top level ...

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:HTMLCode="http://schemas.android.com/apk/res-auto">

    <item android:id="@+id/Examine"
        android:title="@string/Examine"
        HTMLCode:showAsAction="always">

        <menu xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:HTMLCode="http://schemas.android.com/apk/res-auto" >
            <item android:id="@+id/load"
                android:title="@string/load"
                HTMLCode:showAsAction="ifRoom|withText" />

            <item android:id="@+id/findfirst"
                android:title="@string/findfirst"
                HTMLCode:showAsAction="ifRoom|withText" />

            <item android:id="@+id/findnext"
                android:title="@string/FindNext"
                HTMLCode:showAsAction="ifRoom|withText" />
        </menu>
    </item>

    <item android:id="@+id/Redirect"
        android:title="@string/Redirect"
        HTMLCode:showAsAction="ifRoom|withText">

        <menu xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:HTMLCode="http://schemas.android.com/apk/res-auto" >
            <item android:id="@+id/getRedirect"
                android:title="@string/getRedirect"
                HTMLCode:showAsAction="ifRoom|withText" />

            <item android:id="@+id/toggleRedirect"
                android:title="@string/toggleRedirect"
                HTMLCode:showAsAction="ifRoom|withText" />

            <item android:id="@+id/copyRedirect"
                android:title="@string/copyRedirect"
                HTMLCode:showAsAction="ifRoom|withText" />
        </menu>
    </item>
</menu>

回答6:

You should consider use a ActionProvider instead.

public class MyActionProvider extends ActionProvider {

    private Context mContext;

    public MyActionProvider(Context context) {
        super(context);

        mContext = context;
    }

    @Override
    public View onCreateActionView() {
        //LayoutInflater layoutInflater = LayoutInflater.from(mContext);
        return null;
    }

    @Override
    public void onPrepareSubMenu(SubMenu subMenu) {
        super.onPrepareSubMenu(subMenu);

        subMenu.clear();

        subMenu.add("menu 1");
        subMenu.add("menu 2");
        subMenu.add("menu 3");
    }

    @Override
    public boolean hasSubMenu() {
        return true;
    }

    @Override
    public boolean onPerformDefaultAction() {
        return super.onPerformDefaultAction();
    }
}

回答7:

I would just create the submenu in xml file, and in run time get the submenu from menu object, (using findItem(id) method) and use submenu.setVisible(boolean) to add/remove it on run time.

回答8:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/menu1" android:alphabeticShortcut="a"
    android:title="Menu No. 1" android:orderInCategory="1" />
<item android:id="@+id/menu2" android:alphabeticShortcut="b"
    android:title="Menu No. 2" android:orderInCategory="2">
    <menu >
    <group android:id="@+id/group2" android:checkableBehavior="single">
        <item android:id="@+id/submenu1" android:title="SubMenu No. 1" />
        <item android:id="@+id/submenu2" android:title="SubMenu No. 2" />
    </group>   
    </menu>
</item>