Custom buttonbar with overflow menu in Android

Question

In my app, I want to show some buttons in a LinearLayout that expands over whole width of the screen. Depending on screen size and/or orientation, I would like to hide those buttons, that don't fit in the row, in some OverflowMenu, similar to the behaviour of the ActionBar. If possible, I would like to describe the buttons in a menu resource file with the ifRoom|always attributes.

I considered displaying a Toolbar from the latest AppCompat library, but that contains too many elements that I don't need and don't know how to turn off.

Is there some library or simple way to do this?

Answer 1

Here is an example to do what you want. Make sure your ActionMenuView XML item is wrap_content for height and width, then gravity to the right. Surround it in a LinearLayout which takes the whole width and provides background color.

Use this code to initialize the ActionMenuView (obviously you will need to change the button callbacks)

        ActionMenuView actionMenuView = (ActionMenuView) findViewById(R.id.editBar);

        final Context context = this;
        MenuBuilder menuBuilder = new MenuBuilder(context);
        menuBuilder.setCallback(new MenuBuilder.Callback() {
            @Override
            public boolean onMenuItemSelected(MenuBuilder menuBuilder, MenuItem menuItem) {
                return onOptionsItemSelected(menuItem);
            }

            @Override
            public void onMenuModeChange(MenuBuilder menuBuilder) {

            }
        });

        // setup a actionMenuPresenter which will use up as much space as it can, even with width=wrap_content
        ActionMenuPresenter presenter = new ActionMenuPresenter(context);
        presenter.setReserveOverflow(true);
        presenter.setWidthLimit(getResources().getDisplayMetrics().widthPixels, true);
        presenter.setItemLimit(Integer.MAX_VALUE);

        // open a menu xml into the menubuilder
        getMenuInflater().inflate(R.menu.editbar, menuBuilder);

        // runs presenter.initformenu(mMenu) too, setting up presenter's mmenu ref...  this must be before setmenuview
        menuBuilder.addMenuPresenter(presenter, this);

        // runs menuview.initialize too, so menuview.mmenu = mpresenter.mmenu
        actionMenuView.setPresenter(presenter);

        presenter.updateMenuView(true);

For what it's worth, I had to read the support library source code for 8 hours to get this to work. The documentation is garbage.

Answer 2

ActionMenuView is the part of a Toolbar which specifically controls the actions and overflow part of the Toolbar. In your case, you can use an ActionMenuView alone to implement just the actions/overflow part of the Toolbar:

1. Add an ActionMenuView to the appropriate place in your XML layout
2. Retrieve a MenuInflater (easiest way is through an Activity's getMenuInflater() method
3. Call menuInflater.inflate(R.menu.your_menu, actionMenuView.getMenu()) to inflate your menu into the ActionMenuView