导航抽屉

Question

所以，我按照教程添加了一个滑动导航抽屉到我的应用程序（加上我自己的一些调整），但我有点困惑，可能是因为我没有完全克服碎片。基本上我创建了一个溢出菜单，其中Log Out是唯一的选项，所以我可以测试我的登录系统。我希望我的导航抽屉中的注销选项，所以我可以摆脱那个溢出菜单，但我无法弄清楚要更改的内容，以便它注销而不是只显示点击的片段的标题。虽然我问基本相同的问题，如果我想创建有人在点击导航抽屉中的选项时正在查看的页面，我会在哪里这样做？在相应的片段中？

MainActivity.java

package me.paxana.alerta;

import android.app.Activity;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.app.Fragment;
import android.content.Intent;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MenuInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;

import com.parse.ParseUser;

import java.util.ArrayList;
import java.util.List;

import butterknife.Bind;
import butterknife.ButterKnife;
import me.paxana.alerta.adapter.SlidingMenuAdapter;
import me.paxana.alerta.fragment.Fragment1;
import me.paxana.alerta.fragment.Fragment2;
import me.paxana.alerta.fragment.Fragment3;
import me.paxana.alerta.model.ItemSlideMenu;

public class MainActivity extends AppCompatActivity {
    public static final String TAG = MainActivity.class.getSimpleName();
    private List<ItemSlideMenu> listSliding;
    private SlidingMenuAdapter adapter;
    private ListView listViewSliding;
    private DrawerLayout drawerLayout;
    private android.support.v7.app.ActionBarDrawerToggle actionBarDrawerToggle;
    private Toolbar mToolbar;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);


        ParseUser currentUser = ParseUser.getCurrentUser();
             if (currentUser == null) {
                navigateToLogin();
            }

        else {
                Log.i(TAG, currentUser.getUsername());
            }

        listViewSliding = (ListView)findViewById(R.id.lv_sliding_menu);
        drawerLayout = (DrawerLayout)findViewById(R.id.drawer_layout);
        listSliding = new ArrayList<>();
        //add item for sliding list
        listSliding. add(new ItemSlideMenu(R.drawable.ic_action_settings, "Settings"));
        listSliding.add(new ItemSlideMenu(R.drawable.ic_action_about, "About"));
        listSliding.add(new ItemSlideMenu(R.drawable.ic_logout_black_48dp, "Log Out"));
        adapter = new SlidingMenuAdapter(this, listSliding);
        listViewSliding.setAdapter(adapter);


        //display icon to open/close slider
        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(mToolbar);
        assert getSupportActionBar() != null;
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        //set title
        setTitle(listSliding.get(0).getTitle());
        //item selected
        listViewSliding.setItemChecked(0, true);
        //close menu
        drawerLayout.closeDrawer(listViewSliding);
        //handle on item click
        listViewSliding.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                //set title
                setTitle(listSliding.get(position).getTitle());
                //item selected
                listViewSliding.setItemChecked(position, true);
                //close menu
                drawerLayout.closeDrawer(listViewSliding);
            }

        });

        actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.drawer_opened, R.string.drawer_closed) {
            @Override
            public void onDrawerOpened(View drawerView) {
                super.onDrawerOpened(drawerView);
                invalidateOptionsMenu();
            }

            @Override
            public void onDrawerClosed(View drawerView) {
                super.onDrawerClosed(drawerView);
                invalidateOptionsMenu();
            }
        };

        drawerLayout.setDrawerListener(actionBarDrawerToggle);

    }

    private void navigateToLogin() {
        Intent intent = new Intent(this, LoginActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
        startActivity(intent);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
            inflater.inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if(actionBarDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }

        int itemId = item.getItemId();
        if (itemId == R.id.action_logout) {
            ParseUser.logOut();
            navigateToLogin();

        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        actionBarDrawerToggle.syncState();
    }
//create method replace fragment
    private void replaceFragment(int pos) {
        android.support.v4.app.Fragment fragment = null;
        switch (pos) {
            case 0:
                fragment = new Fragment1();
                    break;
            case 1:
                fragment = new Fragment2();
                break;
            case 2:
                fragment = new Fragment3();
                break;
            default:
                fragment = new Fragment1();
                break;
        }
        if(null != fragment) {
            android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
            android.support.v4.app.FragmentTransaction transaction = fragmentManager.beginTransaction();
            transaction.replace(R.id.main_content, fragment);
            transaction.addToBackStack(null);
            transaction.commit();

        }
    }
}

Fragment3 （我尝试将logout选项添加到此片段但无济于事。当我点击它时会发生什么，屏幕上会显示“Log Out”文本）

package me.paxana.alerta.fragment;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.parse.ParseUser;

import me.paxana.alerta.LoginActivity;
import me.paxana.alerta.R;

/**
 * A simple {@link Fragment} subclass.
 * Activities that contain this fragment must implement the
 * {@link Fragment3.OnFragmentInteractionListener} interface
 * to handle interaction events.
 * Use the {@link Fragment3#newInstance} factory method to
 * create an instance of this fragment.
 */
public class Fragment3 extends Fragment {
    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    private OnFragmentInteractionListener mListener;

    public Fragment3() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment Fragment3.
     */
    // TODO: Rename and change types and number of parameters
    public static Fragment3 newInstance(String param1, String param2) {
        Fragment3 fragment = new Fragment3();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ParseUser.logOut();
        Intent intent = new Intent(Fragment3.this.getActivity(), LoginActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
        startActivity(intent);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment3, container, false);
        // Inflate the layout for this fragment
        return rootView;
    }

    // TODO: Rename method, update argument and hook method into UI event
    public void onButtonPressed(Uri uri) {
        if (mListener != null) {
            mListener.onFragmentInteraction(uri);
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }

    /**
     * This interface must be implemented by activities that contain this
     * fragment to allow an interaction in this fragment to be communicated
     * to the activity and potentially other fragments contained in that
     * activity.
     * <p/>
     * See the Android Training lesson <a href=
     * "http://developer.android.com/training/basics/fragments/communicating.html"
     * >Communicating with Other Fragments</a> for more information.
     */
    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        void onFragmentInteraction(Uri uri);
    }
}

Answer 1

我希望它有效：

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if(actionBarDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }

    int itemId = item.getItemId();
    if (itemId == R.id.action_logout) {
        //ParseUser.logOut();
        //navigateToLogin();
        //If you the latest activity was te LoginActivity it goues to the LoginActivity
           finish();

    }
    return super.onOptionsItemSelected(item);
}

或者，如果您尝试从抽屉中进行操作，请将此替换为fragment3：

 private void replaceFragment(int pos) {
    android.support.v4.app.Fragment fragment = null;
    switch (pos) {
        case 0:
            fragment = new Fragment1();
                break;
        case 1:
            fragment = new Fragment2();
            break;
        case 2:
            //fragment = new Fragment3();
              //If you the latest activity was te LoginActivity it goues to the LoginActivity

               finish();

            break;
        default:
            fragment = new Fragment1();
            break;
    }

Answer 2

如果我了解您要查找的内容，可以通过单击导航抽屉列表的注销元素注销：

试试这个：

listViewSliding.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

          if (position == logOutIndex) { //You can do this if you know the position of the logOut button, e.g it's always at the end of the ListVIew

                ParseUser.logOut();
                navigateToLogin();
           }
        }
    });

Answer 3

很难解释，因为你必须这么做才能让它发挥作用。 我的第一个想法是，您粘贴代码以登录 MainActivity.java 中的切换案例：

private void replaceFragment(int pos) {
    android.support.v4.app.Fragment fragment = null;
    switch (pos) {
        case 0:
            fragment = new Fragment1();
                break;
        case 1:
            fragment = new Fragment2();
            break;
        case 2:
            ParseUser.logOut();
            Intent intent = new Intent(Fragment3.this.getActivity(),LoginActivity.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
            startActivity(intent);
            if (getArguments() != null) {
               mParam1 = getArguments().getString(ARG_PARAM1);
               mParam2 = getArguments().getString(ARG_PARAM2);
            }
            fragment = new Fragment3();
            break;
        default:
            fragment = new Fragment1();
            break;
    }
    if(null != fragment) {
        android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
        android.support.v4.app.FragmentTransaction transaction = fragmentManager.beginTransaction();
        transaction.replace(R.id.main_content, fragment);
        ...

我希望我理解你的权利，但这必须解决问题，如果你现在点击第3个片段就必须注销。

如果我错了，请尽快回复，我会寻找另一种解决方案;）