Changing Toolbar and CollapsingToolbarLayout scroll flags programmatically

问题

I have a single Activity android app with lots of fragments. When I'm showing a list screen I want to use the Toolbar with the, app:layout_scrollFlags="scroll|enterAlways" property. And in the detail fragments I want to use the CollapsingToolbarLayout with an image in it. Since it's a single Activity app, I have only one Toolbar. Is it possible to modify my layout programmatically to suit both cases?

回答1:

Yes. Let's say you are going from the CollapsingToolbarLayout fragment to the Toolbar one.

1. You collapse your AppBarLayout using AppBarLayout.setExpanded(false);

2. You change the scroll flags to fit your needs.

   AppBarLayout.LayoutParams p = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
   p.setScrollFlags(...);
   toolbar.setLayoutParams(p);
   

   Same goes for the CollapsingToolbarLayout if necessary. I guess it should be something like:

   collapsingToolbarParams.setScrollFlags(0); //no flags for ctl
   toolbarParams.setScrollFlags(SCROLL_FLAG_SCROLL | SCROLL_FLAG_ENTER_ALWAYS); //new flags for toolbar
   

回答2:

I found it working

public void disableToolBarScrolling() {
    CollapsingToolbarLayout toolbar = findViewById(R.id.collap_toolbar);
    AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
    params.setScrollFlags(0);
}

public void enableToolBarScrolling() {
    CollapsingToolbarLayout toolbar = findViewById(R.id.collap_toolbar);
    AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
    params.setScrollFlags(SCROLL_FLAG_SCROLL | SCROLL_FLAG_ENTER_ALWAYS);
}

来源：https://stackoverflow.com/questions/32418625/changing-toolbar-and-collapsingtoolbarlayout-scroll-flags-programmatically