Question

我如何拒绝用户号码。＆＃34; 1＆＃34;从导航栏访问1个选项卡。我有两种类型的用户：用户1（Tutee）和用户2（Tutor）。如果用户1登录，如何制作，他们将看到＆＃34;申请导师＆＃34;导航栏中的选项卡而不是＆＃34; Tutor Profile＆＃34;。只有用户2才能看到这个＆＃34; Tutor Profile Tab＆＃34;并且可以访问它。有什么建议吗？

所以我在我的数据库上有这个数据结构：

    {
       "users" : {
           "tua3IbbJ2APuLI1z1SesBQlAGCF2" : {
           "birthday" : "02/07/1995",
           "country" : "Zimbabwe",
           "email" : "email@gmail.com",
           "hobby" : "Rugby",
           "name" : "Ainul ",
           "phone" : "646446",
           "uId" : "tua3IbbJ2APuLI1z1SesBQlAGCF2",
           "userType" : "2"
         }
       }
     }

来自我的HomeActivity.java：

    private void setUpNavigationView() {
    //Setting Navigation View Item Selected Listener to handle the item click of the navigation menu
    navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {

        // This method will trigger on item Click of navigation menu
        @Override
        public boolean onNavigationItemSelected(MenuItem menuItem) {

            //Check to see which item was being clicked and perform appropriate action
            switch (menuItem.getItemId()) {
                //Replacing the main content with ContentFragment Which is our Inbox View;
                case R.id.home:
                    navItemIndex = 0;
                    CURRENT_TAG = TAG_HOME;
                    break;
                case R.id.nav_inbox:
                    navItemIndex = 1;
                    CURRENT_TAG = TAG_INBOX;
                    break;
                case R.id.nav_notifications:
                    navItemIndex = 2;
                    CURRENT_TAG = TAG_NOTIFICATIONS;
                    break;
                case R.id.nav_settings:
                    navItemIndex = 3;
                    CURRENT_TAG = TAG_SETTINGS;
                    break;
                case R.id.nav_profile:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, ProfileActivity.class));
                    drawer.closeDrawers();
                    return true;
                case R.id.nav_about_us:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, AboutUsActivity.class));
                    drawer.closeDrawers();
                    return true;
                case R.id.nav_privacy_policy:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, PrivacyPolicyActivity.class));
                    drawer.closeDrawers();
                    return true;
                default:
                    navItemIndex = 0;
            }

            //Checking if the item is in checked state or not, if not make it in checked state
            if (menuItem.isChecked()) {
                menuItem.setChecked(false);
            } else {
                menuItem.setChecked(true);
            }
            menuItem.setChecked(true);

            loadHomeFragment();

            return true;
        }
    });


    ActionBarDrawerToggle actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.openDrawer, R.string.closeDrawer) {

        @Override
        public void onDrawerClosed(View drawerView) {
            // Code here will be triggered once the drawer closes as we dont want anything to happen so we leave this blank
            super.onDrawerClosed(drawerView);
        }

        @Override
        public void onDrawerOpened(View drawerView) {
            // Code here will be triggered once the drawer open as we dont want anything to happen so we leave this blank
            super.onDrawerOpened(drawerView);
        }
    };

    //Setting the actionbarToggle to drawer layout
    drawer.setDrawerListener(actionBarDrawerToggle);

    //calling sync state is necessary or else your hamburger icon wont show up
    actionBarDrawerToggle.syncState();
}

以下是HomeActivity.java的完整编码，以防万一我遗漏了一些内容：

    package com.example.cqaai.tutorpal.activity;
    import android.content.Intent;
    import android.os.Bundle;
    import android.os.Handler;
    import android.support.design.widget.FloatingActionButton;
    import android.support.design.widget.NavigationView;
    import android.support.design.widget.Snackbar;
    import android.support.v4.app.Fragment;
    import android.support.v4.app.FragmentTransaction;
    import android.support.v4.view.GravityCompat;
    import android.support.v4.widget.DrawerLayout;
    import android.support.v7.app.ActionBarDrawerToggle;
    import android.support.v7.app.AppCompatActivity;
    import android.support.v7.widget.Toolbar;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.widget.ImageView;
    import android.widget.TextView;
    import android.widget.Toast;
    import android.support.annotation.NonNull;
    import android.widget.Button;

    import com.bumptech.glide.Glide;
    import com.bumptech.glide.load.engine.DiskCacheStrategy;

    import com.example.cqaai.tutorpal.R;
    import com.example.cqaai.tutorpal.fragment.HomeFragment;
    import com.example.cqaai.tutorpal.fragment.ProfileFragment;
    import com.example.cqaai.tutorpal.fragment.NotificationsFragment;
    import com.example.cqaai.tutorpal.fragment.InboxFragment;
    import com.example.cqaai.tutorpal.fragment.SettingsFragment;
    import com.example.cqaai.tutorpal.other.CircleTransform;

    import com.google.firebase.auth.FirebaseAuth;
    import com.google.firebase.auth.FirebaseUser;

    public class HomeActivity extends AppCompatActivity {

private NavigationView navigationView;
private DrawerLayout drawer;
private View navHeader;
private ImageView imgNavHeaderBg, imgProfile;
private TextView txtName, txtWebsite;
private Toolbar toolbar;
private FloatingActionButton fab;

private Button btnSettings;
private FirebaseAuth.AuthStateListener authListener;
private FirebaseAuth auth;

// urls to load navigation header background image
// and profile image
private static final String urlNavHeaderBg = "http://api.androidhive.info/images/nav-menu-header-bg.jpg";
private static final String urlProfileImg = "private static final String urlProfileImg = \"https://lh3.googleusercontent.com/eCtE_G34M9ygdkmOpYvCag1vBARCmZwnVS6rS5t4JLzJ6QgQSBquM0nuTsCpLhYbKljoyS-txg\";\n";

// index to identify current nav menu item
public static int navItemIndex = 0;

// tags used to attach the fragments
private static final String TAG_HOME = "home";
private static final String TAG_PROFILE = "profile";
private static final String TAG_INBOX = "inbox";
private static final String TAG_NOTIFICATIONS = "notifications";
private static final String TAG_SETTINGS = "settings";
public static String CURRENT_TAG = TAG_HOME;

// toolbar titles respected to selected nav menu item
private String[] activityTitles;

// flag to load home fragment when user presses back key
private boolean shouldLoadHomeFragOnBackPress = true;
private Handler mHandler;


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

    //get firebase auth instance
    auth = FirebaseAuth.getInstance();

    //get current user
    final FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();

    authListener = new FirebaseAuth.AuthStateListener() {
        @Override
        public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
            FirebaseUser user = firebaseAuth.getCurrentUser();
            if (user == null) {
                // user auth state is changed - user is null
                // launch login activity
                startActivity(new Intent(HomeActivity.this, LoginActivity.class));
                finish();
            }
        }
    };



    toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    mHandler = new Handler();

    drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    navigationView = (NavigationView) findViewById(R.id.nav_view);
    fab = (FloatingActionButton) findViewById(R.id.fab);

    // Navigation view header
    navHeader = navigationView.getHeaderView(0);
    txtName = (TextView) navHeader.findViewById(R.id.name);
    txtWebsite = (TextView) navHeader.findViewById(R.id.website);
    imgNavHeaderBg = (ImageView) navHeader.findViewById(R.id.img_header_bg);
    imgProfile = (ImageView) navHeader.findViewById(R.id.img_profile);

    // load toolbar titles from string resources
    activityTitles = getResources().getStringArray(R.array.nav_item_activity_titles);

    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });

    // load nav menu header data
    loadNavHeader();

    // initializing navigation menu
    setUpNavigationView();

    if (savedInstanceState == null) {
        navItemIndex = 0;
        CURRENT_TAG = TAG_HOME;
        loadHomeFragment();
    }
}

/***
 * Load navigation menu header information
 * like background image, profile image
 * name, website, notifications action view (dot)
 */



private void loadNavHeader() {
    // name, website
    txtName.setText("Ainul Fitiri");
    txtWebsite.setText("@ainulfi3");

    // loading header background image
    Glide.with(this).load(urlNavHeaderBg)
            .crossFade()
            .diskCacheStrategy(DiskCacheStrategy.ALL)
            .into(imgNavHeaderBg);

    // Loading profile image
    Glide.with(this).load(urlProfileImg)
            .crossFade()
            .thumbnail(0.5f)
            .bitmapTransform(new CircleTransform(this))
            .diskCacheStrategy(DiskCacheStrategy.ALL)
            .into(imgProfile);

    // showing dot next to notifications label
    navigationView.getMenu().getItem(3).setActionView(R.layout.menu_dot);
}

/***
 * Returns respected fragment that user
 * selected from navigation menu
 */
private void loadHomeFragment() {
    // selecting appropriate nav menu item
    selectNavMenu();

    // set toolbar title
    setToolbarTitle();

    // if user select the current navigation menu again, don't do anything
    // just close the navigation drawer
    if (getSupportFragmentManager().findFragmentByTag(CURRENT_TAG) != null) {
        drawer.closeDrawers();

        // show or hide the fab button
        toggleFab();
        return;
    }

    // Sometimes, when fragment has huge data, screen seems hanging
    // when switching between navigation menus
    // So using runnable, the fragment is loaded with cross fade effect
    // This effect can be seen in GMail app
    Runnable mPendingRunnable = new Runnable() {
        @Override
        public void run() {
            // update the main content by replacing fragments
            Fragment fragment = getHomeFragment();
            FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
            fragmentTransaction.setCustomAnimations(android.R.anim.fade_in,
                    android.R.anim.fade_out);
            fragmentTransaction.replace(R.id.frame, fragment, CURRENT_TAG);
            fragmentTransaction.commitAllowingStateLoss();
        }
    };

    // If mPendingRunnable is not null, then add to the message queue
    if (mPendingRunnable != null) {
        mHandler.post(mPendingRunnable);
    }

    // show or hide the fab button
    toggleFab();

    //Closing drawer on item click
    drawer.closeDrawers();

    // refresh toolbar menu
    invalidateOptionsMenu();
}

private Fragment getHomeFragment() {
    switch (navItemIndex) {
        case 0:
            // home
            HomeFragment homeFragment = new HomeFragment();
            return homeFragment;
        case 1:
            // Inbox fragment
            InboxFragment inboxFragment = new InboxFragment();
            return inboxFragment;
        case 2:
            // notifications fragment
            NotificationsFragment notificationsFragment = new NotificationsFragment();
            return notificationsFragment;

        case 3:
            // settings fragment
            SettingsFragment settingsFragment = new SettingsFragment();
            return settingsFragment;
        default:
            return new HomeFragment();
    }
}

private void setToolbarTitle() {
    getSupportActionBar().setTitle(activityTitles[navItemIndex]);
}

private void selectNavMenu() {
    navigationView.getMenu().getItem(navItemIndex).setChecked(true);
}

private void setUpNavigationView() {
    //Setting Navigation View Item Selected Listener to handle the item click of the navigation menu
    navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {

        // This method will trigger on item Click of navigation menu
        @Override
        public boolean onNavigationItemSelected(MenuItem menuItem) {

            //Check to see which item was being clicked and perform appropriate action
            switch (menuItem.getItemId()) {
                //Replacing the main content with ContentFragment Which is our Inbox View;
                case R.id.home:
                    navItemIndex = 0;
                    CURRENT_TAG = TAG_HOME;
                    break;
                case R.id.nav_profile:
                    navItemIndex = 1;
                    CURRENT_TAG = TAG_PROFILE;
                    break;
                case R.id.nav_inbox:
                    navItemIndex = 1;
                    CURRENT_TAG = TAG_INBOX;
                    break;
                case R.id.nav_notifications:
                    navItemIndex = 2;
                    CURRENT_TAG = TAG_NOTIFICATIONS;
                    break;
                case R.id.nav_settings:
                    navItemIndex = 3;
                    CURRENT_TAG = TAG_SETTINGS;
                    break;
                case R.id.nav_profile:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, ProfileActivity.class));
                    drawer.closeDrawers();
                    return true;
                case R.id.nav_about_us:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, AboutUsActivity.class));
                    drawer.closeDrawers();
                    return true;
                case R.id.nav_privacy_policy:
                    // launch new intent instead of loading fragment
                    startActivity(new Intent(HomeActivity.this, PrivacyPolicyActivity.class));
                    drawer.closeDrawers();
                    return true;
                default:
                    navItemIndex = 0;
            }

            //Checking if the item is in checked state or not, if not make it in checked state
            if (menuItem.isChecked()) {
                menuItem.setChecked(false);
            } else {
                menuItem.setChecked(true);
            }
            menuItem.setChecked(true);

            loadHomeFragment();

            return true;
        }
    });


    ActionBarDrawerToggle actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.openDrawer, R.string.closeDrawer) {

        @Override
        public void onDrawerClosed(View drawerView) {
            // Code here will be triggered once the drawer closes as we dont want anything to happen so we leave this blank
            super.onDrawerClosed(drawerView);
        }

        @Override
        public void onDrawerOpened(View drawerView) {
            // Code here will be triggered once the drawer open as we dont want anything to happen so we leave this blank
            super.onDrawerOpened(drawerView);
        }
    };

    //Setting the actionbarToggle to drawer layout
    drawer.setDrawerListener(actionBarDrawerToggle);

    //calling sync state is necessary or else your hamburger icon wont show up
    actionBarDrawerToggle.syncState();
}

@Override
public void onBackPressed() {
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawers();
        return;
    }

    // This code loads home fragment when back key is pressed
    // when user is in other fragment than home
    if (shouldLoadHomeFragOnBackPress) {
        // checking if user is on other navigation menu
        // rather than home
        if (navItemIndex != 0) {
            navItemIndex = 0;
            CURRENT_TAG = TAG_HOME;
            loadHomeFragment();
            return;
        }


    }

    super.onBackPressed();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.

    // show menu only when home fragment is selected
    if (navItemIndex == 0) {
        getMenuInflater().inflate(R.menu.main, menu);

    }

    // when fragment is notifications, load the menu created for notifications
    if (navItemIndex == 3) {
        getMenuInflater().inflate(R.menu.notifications, menu);
    }
    return true;
}



@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_logout) {
        //signing out user
        auth.signOut();
        Intent intent = new Intent(HomeActivity.this, LoginActivity.class);
        startActivity(intent);

        Toast.makeText(getApplicationContext(), "Logout user!", Toast.LENGTH_LONG).show();
        return true;
    }

    // user is in notifications fragment
    // and selected 'Mark all as Read'
    if (id == R.id.action_mark_all_read) {
        Toast.makeText(getApplicationContext(), "All notifications marked as read!", Toast.LENGTH_LONG).show();
    }

    // user is in notifications fragment
    // and selected 'Clear All'
    if (id == R.id.action_clear_notifications) {
        Toast.makeText(getApplicationContext(), "Clear all notifications!", Toast.LENGTH_LONG).show();
    }

    return super.onOptionsItemSelected(item);
}

// show or hide the fab
private void toggleFab() {
    if (navItemIndex == 0)
        fab.show();
    else
        fab.hide();
}

}

Answer 1

实现此目的的一种方法是使用SharedPreferences，因此您只需存储userType并检查它是类型1（Tutee）还是类型2（Tutor）。

首先，您需要获取已登录用户的userType，因此可能会进入您的登录屏幕：

databaseReference.addValueEventListener(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {

        String userType = dataSnapshot.child("users").child(task.getResult().getUser().getUid()).getValue(User.class).getUId();

        SharedPreferences sharedPreferences = getSharedPreferences("prefs", MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putString("userType", userType);
        editor.commit();                   

    }

    @Override
    public void onCancelled(DatabaseError databaseError) {
        // NO-OP
    }
});

User类应该是您的用户POJO或您在模型中为用户提供的任何类。

现在，您可以从SharedPreferences中检索userType，并设置条件以隐藏或显示NavigationView菜单中的项目：

SharedPreferences sharedPreferences = getSharedPreferences("prefs", MODE_PRIVATE);
if (sharedPreferences.getString("userType", 1).equals("1")) {
    navigationView.getMenu().findItem(R.id.ITEM_ID).setVisible(false);
} else {
    navigationView.getMenu().findItem(R.id.ITEM_ID).setVisible(true);
}

上面的代码应该放在你的setUpNavigationView（）方法中。如果您愿意，请在用户注销时清除首选项：

editor.clear(); 
editor.commit();

希望这会有所帮助;）

Android Firebase获取用户信息以限制访问权限

1 个答案: