如何使用Android导航抽屉更改片段

Question

我知道这些类型的问题已经在这里,但我仍然没有找到这个问题的答案:

• 我创建了一个应用程序并使用了由应用程序自动创建的导航抽屉(AndroidStudio)

这就是我所拥有的:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mNavigationDrawerFragment = (NavigationDrawerFragment)
            getFragmentManager().findFragmentById(R.id.navigation_drawer);
    mTitle = getTitle();

    // Set up the drawer.
    mNavigationDrawerFragment.setUp(
            R.id.navigation_drawer,
            (DrawerLayout) findViewById(R.id.drawer_layout));
}

@Override
public void onNavigationDrawerItemSelected(int position) {
    // update the main content by replacing fragments
    FragmentManager fragmentManager = getFragmentManager();
    fragmentManager.beginTransaction()
            .replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
            .commit();
}

public void onSectionAttached(int number) {
    switch (number) {
        case 1:

            break;
        case 2:

            break;
        case 3:

            break;
    }
}

还有一些在这里:

    public static PlaceholderFragment newInstance(int sectionNumber) {
        PlaceholderFragment fragment = new PlaceholderFragment();
        Bundle args = new Bundle();
        args.putInt(ARG_SECTION_NUMBER, sectionNumber);
        fragment.setArguments(args);
        return fragment;
    }

    public PlaceholderFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_main, container, false);
        return rootView;
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        ((MainActivity) activity).onSectionAttached(
                getArguments().getInt(ARG_SECTION_NUMBER));
    }
}

我想使用导航抽屉中的按钮显示另一个片段.我想使用这个代码,所以请不要给我任何指南或教程制作自己的抽屉..

问题是,放入什么case 1: case 2:以及case 3:我想打开另一个片段？感谢名单.

还有一个问题:

• 如何添加更多片段和事务？这不起作用 -

  Fragment fragment = new MyFragment1();
  Fragment frag = new MyFragment2();
  FragmentManager fragmentManager = getFragmentManager();
  switch(position) {
      case 0:
          fragment = new MyFragment1();
          break;
      case 1:
          frag = new MyFragment2();
  
          break;
  }
  fragmentManager.beginTransaction()
          .replace(R.id.container, fragment).commit();
  

  }

Answer 1

您应该只将switch语句放入onNavigationDrawerItemSelected方法中.

这样的事情应该有效:

public void onNavigationDrawerItemSelected(int position) {
    // update the main content by replacing fragments
    Fragment fragment;
    FragmentManager fragmentManager = getFragmentManager(); // For AppCompat use getSupportFragmentManager
    switch(position) {
        default:
        case 0:
            fragment = new MyFragment1();
            break;
        case 1:
            fragment = new MyFragment2();
            break;
    }
    fragmentManager.beginTransaction()
        .replace(R.id.container, fragment)
        .commit();
}

这很快就完成了,但我认为它应该有效

Answer 2

我解决了这个问题inflater:

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView;
        switch(getArguments().getInt(ARG_SECTION_NUMBER)) {
            case 1:
                rootView = inflater.inflate(R.layout.fragment_obj_detail, container, false);
                break;
            case 2:
                rootView = inflater.inflate(R.layout.fragment_obj_list, container, false);
                break;
            case 3:
                rootView = inflater.inflate(R.layout.fragment_obj_list, container, false);
                break;
            case 4:
                rootView = inflater.inflate(R.layout.fragment_about, container, false);
                break;
            default:
                rootView = inflater.inflate(R.layout.fragment_obj_list, container, false);
        }
        return rootView;
    }

Answer 3

你需要在switch里面创建一个块,onNavigationDrawerItemSelected(然后使用已经存在的代码,而不是case使用相应Fragment的代码PlaceholderFragment.现在,它包含一个通用的代码片段,用于添加PlaceholderFragment布局,将其重用于您的目的.