android - 抽屉导航 ListView 位置不刷新

Question

我的应用程序中有一个 NavigationDrawer，我的抽屉中有五个项目:

• 主页
• 帐户
• 股票
• 帮助
• 退出

现在，如果用户点击注销，它会显示两个项目:

• 主页
• 登录

现在的问题是当用户点击登录时总是会看到账户

 public class MainActivity extends FragmentActivity {
    private DrawerLayout mDrawerLayout;
    private ListView mDrawerList;
    private ActionBarDrawerToggle mDrawerToggle;
    private String abc;

    private Intent ii;
    // nav drawer title
    private CharSequence mDrawerTitle;

    // used to store app title
    private CharSequence mTitle;

    // slide menu items
    private String[] navMenuTitles;
    private TypedArray navMenuIcons;

    private ArrayList<NavDrawerItem> navDrawerItems;
    private NavDrawerListAdapter adapter;

    SharedPreferences prefs;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
        prefs.edit().putBoolean("locked", true).commit();


        ii=getIntent();


        mTitle = mDrawerTitle = getTitle();

        // load slide menu items
        navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);

        // nav drawer icons from resources
        navMenuIcons = getResources()
                .obtainTypedArray(R.array.nav_drawer_icons);

        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerList = (ListView) findViewById(R.id.list_slidermenu);



        navDrawerItems = new ArrayList<NavDrawerItem>();



        // empty the adapter array


        navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1), 0));
        navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1), 5));


        /*navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1)));
        // Find People
        navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1)));
        // Photos
        navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -1)));
        // Communities, Will add a counter here
        navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons.getResourceId(3, -1)));
        // Pages
        navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons.getResourceId(4, -1)));*/

        //  navDrawerItems.remove(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1)));
        // What's hot, We  will add a counter here
        //navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1)));

        // Recycle the typed array
        //navMenuIcons.recycle();

        mDrawerList.setOnItemClickListener(new SlideMenuClickListener());

        // setting the nav drawer list adapter



        adapter = new NavDrawerListAdapter(getApplicationContext(),
                navDrawerItems);
        mDrawerList.setAdapter(adapter);


        // enabling action bar app icon and behaving it as toggle button
        getActionBar().setDisplayHomeAsUpEnabled(true);
        getActionBar().setHomeButtonEnabled(true);

        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
                R.drawable.ic_drawer, //nav menu toggle icon
                R.string.app_name, // nav drawer open - description for accessibility
                R.string.app_name // nav drawer close - description for accessibility
        ) {
            public void onDrawerClosed(View view) {
                getActionBar().setTitle(mTitle);
                // calling onPrepareOptionsMenu() to show action bar icons
                invalidateOptionsMenu();
            }

            public void onDrawerOpened(View drawerView) {
                getActionBar().setTitle(mDrawerTitle);


                //boolean isUserLoggedOut = getPrefBoolean("pref_is_user_logged_out",false);

                //Boolean isUserLoggedOut = prefs.getBoolean("locked", false);


/*
                boolean locked = true;
                SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences();*/

                // Check Condition and Update list as required
                /*if(isUserLoggedOut){
                    navDrawerItems.clear();

                    // Home
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1),0));                   // Login
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1),5));
                }else{
                    navDrawerItems.clear();

                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1),0));
                    // Find People
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1),1));
                    // Photos
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -1),2));
                    // Communities, Will add a counter here
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons.getResourceId(3, -1),3));
                    // Pages
                    navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons.getResourceId(4, -1),4));

                }

                adapter.notifyDataSetChanged();
*/
                // calling onPrepareOptionsMenu() to hide action bar icons
                invalidateOptionsMenu();
            }
        };
        mDrawerLayout.setDrawerListener(mDrawerToggle);

        if (savedInstanceState == null) {
            // on first time display view for first nav item
            displayView(0);
        }
    }

    /**
     * Slide menu item click listener
     * */
    private class SlideMenuClickListener implements
            ListView.OnItemClickListener {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position,
                                long id) {
            // display view for selected nav drawer item

            // Get the item that was selected
            NavDrawerItem item = navDrawerItems.get(position);
            // display view for selected nav drawer item
            displayView(item.thingToDo);



            if(position == 4) { // position of Sign out button

                navDrawerItems.clear(); // empty the adapter array

                navMenuIcons.recycle();

                navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1),0));
                navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1),5));

                //navDrawerItems.remove(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1)));


                adapter.notifyDataSetChanged();


            }
            else {
                if (ii.hasExtra("login")) {
                    abc = ii.getStringExtra("login");

                    if (abc == ii.getStringExtra("login")) {
                        navDrawerItems.clear();

                        navMenuIcons.recycle();

                        navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1),0));
                        // Find People
                        navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1),1));
                        // Photos
                        navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -1),2));
                        // Communities, Will add a counter here
                        navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons.getResourceId(3, -1),3));
                        // Pages
                        navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons.getResourceId(4, -1),4));

                    //  navDrawerItems.remove(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1)));

                        adapter.notifyDataSetChanged();
                        Toast.makeText(MainActivity.this, "success" + abc, Toast.LENGTH_LONG).show();
                    } else {
                        Toast.makeText(MainActivity.this, "unsuccess" + abc, Toast.LENGTH_LONG).show();
                    }
                }


            }






        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // toggle nav drawer on selecting action bar app icon/title
        if (mDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }
        // Handle action bar actions click
        switch (item.getItemId()) {
            case R.id.action_settings:
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }

    /* *
     * Called when invalidateOptionsMenu() is triggered
     */
    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {
        // if nav drawer is opened, hide the action items
        boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
        menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
        return super.onPrepareOptionsMenu(menu);
    }

    /**
     * Diplaying fragment view for selected nav drawer list item
     * */
    private void displayView(int position) {
        // update the main content by replacing fragments
        Fragment fragment = null;
        switch (position) {
            case 0:
                fragment = new HomeFragment();
                break;


            case 1:
            fragment = new FindPeopleFragment();
                break;
            case 2:
                fragment = new PhotosFragment();
                break;
            case 3:
                fragment = new CommunityFragment();
                break;
            case 4:
                fragment = new LoginActivity();
                break;
            case 5:
                fragment = new LoginActivity();
                break;
            default:
                break;
        }


        if (fragment != null) {
            FragmentManager fragmentManager = getSupportFragmentManager();
            fragmentManager.beginTransaction()
                    .replace(R.id.frame_container, fragment).commit();

            // update selected item and title, then close the drawer
            mDrawerList.setItemChecked(position, true);
            mDrawerList.setSelection(position);
            setTitle(navMenuTitles[position]);
            mDrawerLayout.closeDrawer(mDrawerList);
        } else {
            // error in creating fragment
            Log.e("MainActivity", "Error in creating fragment");
        }
    }

    @Override
    public void setTitle(CharSequence title) {
        mTitle = title;
        getActionBar().setTitle(mTitle);
    }



    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        // Sync the toggle state after onRestoreInstanceState has occurred.
        mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        // Pass any configuration change to the drawer toggls
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

}

适配器

public class NavDrawerListAdapter extends BaseAdapter {

    private Context context;
    private ArrayList<NavDrawerItem> navDrawerItems;

    public NavDrawerListAdapter(Context context, ArrayList<NavDrawerItem> navDrawerItems){
        this.context = context;
        this.navDrawerItems = navDrawerItems;
    }

    @Override
    public int getCount() {
        return navDrawerItems.size();
    }

    @Override
    public Object getItem(int position) {       
        return navDrawerItems.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView == null) {
            LayoutInflater mInflater = (LayoutInflater)
                    context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
            convertView = mInflater.inflate(R.layout.drawer_list_item, null);
        }

        ImageView imgIcon = (ImageView) convertView.findViewById(R.id.icon);
        TextView txtTitle = (TextView) convertView.findViewById(R.id.title);
        TextView txtCount = (TextView) convertView.findViewById(R.id.counter);

        imgIcon.setImageResource(navDrawerItems.get(position).getIcon());        
        txtTitle.setText(navDrawerItems.get(position).getTitle());

        // displaying count
        // check whether it set visible or not
        if(navDrawerItems.get(position).getCounterVisibility()){
            txtCount.setText(navDrawerItems.get(position).getCount());
        }else{
            // hide the counter view
            txtCount.setVisibility(View.GONE);
        }

        return convertView;
    }

}

登录 Activity

public class LoginActivity extends Fragment{

    public LoginActivity(){}

    private Button alreadymember;
    private Button checkout;
    private Button forgotpass;

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

        alreadymember=(Button)rootView.findViewById(R.id.btn_login_alredymember);
        forgotpass=(Button)rootView.findViewById(R.id.login_forgot_pwd);
        checkout=(Button)rootView.findViewById(R.id.checkout_login);

        alreadymember.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

               Intent intent=new Intent(getActivity(),MainActivity.class);
                intent.putExtra("login","login");
                startActivity(intent);
               /* HomeFragment tf = new HomeFragment();
                android.support.v4.app.FragmentManager fm = getFragmentManager();
                android.support.v4.app.FragmentTransaction ft = fm.beginTransaction();
                Bundle bundle = new Bundle();
                bundle.putString("login", "login");
                tf.setArguments(bundle);
                ft.replace(R.id.frame_container, tf);
                ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
                ft.addToBackStack(null);
                ft.commit();*/
            }
        });

        forgotpass.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Forgot_Password tf = new Forgot_Password();
                android.support.v4.app.FragmentManager fm = getFragmentManager();
                android.support.v4.app.FragmentTransaction ft = fm.beginTransaction();
                ft.replace(R.id.frame_container, tf);
                ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
                ft.addToBackStack(null);
                ft.commit();
            }
        });


        checkout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                CheckoutBeforeLogin tf = new CheckoutBeforeLogin();
                android.support.v4.app.FragmentManager fm = getFragmentManager();
                android.support.v4.app.FragmentTransaction ft = fm.beginTransaction();
                ft.replace(R.id.frame_container, tf);
                ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
                ft.addToBackStack(null);
                ft.commit();
            }
        });
        return rootView;
    }
}

Answer 1

您总是使用 NavDrawerItems 列表中选定的索引位置调用 displayView()。在用户注销的情况下，列表中只有 2 个项目。当用户选择“登录”时，索引位置为1，而不是5。

您可能想向 NavDrawerItem 添加一个变量，它表示当用户选择该项目时要显示的 Fragment。您可以使用 int 值，然后将该值传递给 displayView()，或者您可以使用 Fragment 的类名来显示。

编辑:添加示例代码

在 NavDrawerItem 中，您应该有如下内容:

String title;
Icon icon;

添加以下内容:

int thingToDo;

然后，在NavDrawerItem的构造函数中，在构造函数中添加一个int参数来初始化字段，如下所示:

public NavDrawerItem(String title, Icon icon, int thingToDo) {
    this.title = title;
    this.icon = icon;
    this.thingToDo = thingToDo;
}

更改所有创建新 NavDrawerItem 实例的调用，以包含“待办事项”，如下所示:

    navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1), 0));
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1), 5));

然后，在 SlideMenuClickListener.onItemClick() 方法中，执行以下操作:

public void onItemClick(AdapterView<?> parent, View view, int position,
                        long id) {
    // Get the item that was selected
    NavDrawerItem item = navDrawerItems.get(position);
    // display view for selected nav drawer item
    displayView(item.thingToDo);
}