我想实现一个抽屉式导航，它隐藏在每当打开抽屉的动作条中的菜单项。

I'm trying to implement a Navigation Drawer that hides the menu items in the ActionBar whenever the drawer is opened.

我下面谷歌的文档，但他们的code没有产生预期的行为。

I am following google's documentation, however their code does not produce the expected behavior.

http://developer.android.com/training/implementing-navigation/nav-drawer.html

使用这个code，当抽屉变的完全打开的菜单项是隐藏的，当抽屉变成完全封闭所示。

Using this code, the menu items are hidden when the drawer becomes completely opened , and shown when the drawer becomes completely closed.

不过，Gmail应用程序的行为有所不同。菜单项目一旦抽屉的打开任意量的隐藏。这就是我想要的行为。有谁知道如何实现这一目标？

However, the Gmail app behaves differently. The menu items are hidden as soon as the drawer opens by any amount. This is the behavior I want. Does anyone know how to achieve this?

谢谢！

推荐答案

你有没有尝试过这样的：

Have you tried this:

迭代的 prepareOptionsMenu（功能菜单）上的每个菜单项键，将其隐藏。 Use invalidateOptionsMenu() whenever you toggle the nav drawer, by measuring the sliding offset.

Iterate over each menu item in onPrepareOptionsMenu(Menu menu) and hide it.

@Override

public boolean onPrepareOptionsMenu(Menu menu) {

    // If the nav drawer is open, hide action items related to the content view
    boolean drawerOpen = shouldGoInvisible;
    hideMenuItems(menu, !drawerOpen);
    return super.onPrepareOptionsMenu(menu);
}

private void hideMenuItems(Menu menu, boolean visible)
{

    for(int i = 0; i < menu.size(); i++){

        menu.getItem(i).setVisible(visible);

    }
}

检测多少资产净值抽屉滑动了：

Detecting how much the nav drawer has slided:

     mDrawerLayout.setDrawerListener(new DrawerListener(){
                    float mPreviousOffset = 0f;

        @Override
        public void onDrawerClosed(View arg0) {
                         super.onDrawerClosed(arg0);
                         shouldGoInvisible = false;
                         invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
        }

        @Override
        public void onDrawerOpened(View arg0) {
                         super.onDrawerOpened(arg0);
                         shouldGoInvisible = true;
                         invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
        }

        @Override
        public void onDrawerSlide(View arg0, float slideOffset) {
             super.onDrawerSlide(arg0, slideOffset);
             if(slideOffset > mPreviousOffset && !shouldGoInvisible){
                shouldGoInvisible = true;
                invalidateOptionsMenu();
            }else if(mPreviousOffset > slideOffset && slideOffset < 0.5f && shouldGoInvisible){
                shouldGoInvisible = false;
                invalidateOptionsMenu();
            }
            mPreviousOffset = slideOffset;


        }

        @Override
        public void onDrawerStateChanged(int arg0) {
            // or use states of the drawer to hide/show the items

        }});

注： shouldGoInvisible 是类的字段。