一个简单的AppBarLayout.OnOffsetChangedListener应该仅使用内置视图来解决问题:

A simple AppBarLayout.OnOffsetChangedListener should do the trick using only built-in views:

AppBarLayout appBarLayout = (AppBarLayout) findViewById(R.id.app_bar);
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener {
    @Override
    public void onOffsetChanged(AppBarLayout appBarLayout, int offset) {
            ActionBar actionBar = getSupportActionBar();
            boolean toolbarCollapsed = Math.abs(offset) >= appBarLayout.getTotalScrollRange();
            actionBar.setTitle(toolbarCollapsed ? yourTitle : "");
            actionBar.setSubtitle(toolbarCollapsed ? yourSubTitle : "");
        }
});

(此代码最初是用C#(Xamarin)而不是Java编写的，因此可能需要进行少量修改)

(This code originally was written in C# (Xamarin), not Java, so minor modifications may be needed)