java - 如何将nestedscrollview动画设置到底部

Question

我正在尝试展开折叠工具栏。当我释放 Nestedscrollview 时，我现在可以折叠工具栏，它几乎折叠起来。问题是，我不知道如何在我释放它几乎扩展时为扩展设置动画。

这是我的代码:

nestedScrollView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction()){
                    case MotionEvent.ACTION_UP:
                        Log.d("Touch", "Toque down");

                        CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
                        AppBarLayout.Behavior behavior = (AppBarLayout.Behavior) params.getBehavior();
                        if (behavior != null) {
                            Log.d("Touch", "Behavior chamado");
                            if(isCompressed) {
                                behavior.onNestedFling(coordinatorLayout, appBarLayout, null, 0, 10000, true);
                            } else{
                               //How can I make it go down??
                            }
                        }

                        return false;
                }

                Log.d("Touch", "Toque");
                return false;
            }

此代码使我的栏在几乎折叠时折叠...如何使其在几乎展开时向下滚动？

Answer 1

这是你应该做的:

NestedScrollView nestedScrollView = (NestedScrollView)getActivity().findViewById(R.id.your_nested_scroll_view);

int toolbarHeight = getActivity().findViewById(R.id.toolbar).getHeight();

nestedScrollView.startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
nestedScrollView.dispatchNestedPreScroll(0, toolbarHeight, null, null);
nestedScrollView.dispatchNestedScroll(0, 0, 0, 0, new int[]{0, -toolbarHeight});
nestedScrollView.scrollTo(0, nestedScrollView.getBottom());

或者你可以使用:

nestedScrollView.fullScroll(View.FOCUS_DOWN);
nestedScrollView.fullScroll(View.FOCUS_UP);