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Navigation drawer: How do I set the selected item at startup?

由 隐身守侯 提交于 2019-12-17 02:53:16

问题


My code works perfectly: every time an item in Navigation Drawer is clicked the item is selected.

Of course I want to start the app with a default fragment (home), but Navigation Drawer doesn't have the item selected. How can I select that item programmatically?

public class BaseApp extends AppCompatActivity {

    //Defining Variables
    protected String LOGTAG = "LOGDEBUG";
    protected Toolbar toolbar;
    protected NavigationView navigationView;
    protected DrawerLayout drawerLayout;

    private DateManager db = null;

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

        navigationView = (NavigationView) findViewById(R.id.navigation_view);


        // set the home/dashboard at startup

        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
        fragmentTransaction.replace(R.id.frame, new DashboardFragment());
        fragmentTransaction.commit();

        setNavDrawer();
    }

    private void setNavDrawer(){

        // Initializing Toolbar and setting it as the actionbar
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        //Initializing NavigationView

        //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) {


                //Checking if the item is in checked state or not, if not make it in checked state

                // I THINK THAT I NEED EDIT HERE...

                if (menuItem.isChecked()) menuItem.setChecked(false);
                else menuItem.setChecked(true);

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


                //Check to see which item was being clicked and perform appropriate action
                switch (menuItem.getItemId()) {    

                    //Replacing the main content with ContentFragment 

                    case R.id.home:

                        DashboardFragment dashboardFragment = new DashboardFragment();
                        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
                        fragmentTransaction.replace(R.id.frame, dashboardFragment,"DASHBOARD_FRAGMENT");
                        fragmentTransaction.commit();
                        return true;
[...]

I think that I need to edit here:

if (menuItem.isChecked()) menuItem.setChecked(false);
                    else menuItem.setChecked(true);

Or in onCreate at App startup with FragmentTransaction.

Thank you for your support.


回答1:


Use the code below:

navigationView.getMenu().getItem(0).setChecked(true);

Call this method after you call setNavDrawer();

The getItem(int index) method gets the MenuItem then you can call the setChecked(true); on that MenuItem, all you are left to do is to find out which element index does the default have, and replace the 0 with that index.

You can select(highlight) the item by calling

onNavigationItemSelected(navigationView.getMenu().getItem(0));

Here is a reference link: http://thegeekyland.blogspot.com/2015/11/navigation-drawer-how-set-selected-item.html

EDIT Did not work on nexus 4, support library revision 24.0.0. I recommend use

navigationView.setCheckedItem(R.id.nav_item);

answered by @kingston below.




回答2:


You can also call:

navigationView.setCheckedItem(id);

This method was introduced in API 23.0.0

Example

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      tools:ignore="UnusedIds">

    <group
        android:id="@+id/group"
        android:checkableBehavior="single">
        <item
            android:id="@+id/menu_nav_home"
            android:icon="@drawable/ic_home_black_24dp"
            android:title="@string/menu_nav_home" />
    </group>
</menu>

Note: android:checkableBehavior="single"

See also this




回答3:


For me both these methods didn't work:

  • navigationView.getMenu().getItem(0).setChecked(true);
  • navigationView.setCheckedItem(id);

Try this one, it works for me.

onNavigationItemSelected(navigationView.getMenu().findItem(R.id.nav_profile));




回答4:


Example (NavigationView.OnNavigationItemSelectedListener):

private void setFirstItemNavigationView() {
        navigationView.setCheckedItem(R.id.custom_id);
        navigationView.getMenu().performIdentifierAction(R.id.custom_id, 0);
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setFirstItemNavigationView();
}

@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
    FragmentManager fragmentManager = getFragmentManager();

    switch (item.getItemId()) {
        case R.id.custom_id:
            Fragment frag = new CustomFragment();

            // update the main content by replacing fragments
            fragmentManager.beginTransaction()
                    .replace(R.id.viewholder_container, frag)
                    .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
                    .addToBackStack(null)
                    .commit();
            break;
    }

Tks




回答5:


There are always problems with Googles "oh so great" support libs. If you want to check an item without downgrading your support libs version, just set checkable before setting checked state. 

MenuItem item = drawer.getMenu().findItem(R.id.action_something);
item.setCheckable(true);
item.setChecked(true);

It might also work if you set checkable in the menu xml files




回答6:


You can both highlight and select the item with the following 1-liner:

navigationView.getMenu().performIdentifierAction(R.id.posts, 0);

Source: https://stackoverflow.com/a/31044917/383761




回答7:


API 23 provides the following method:

navigationView.setCheckedItem(R.id.nav_item_id);

However, for some reason this function did not cause the code behind the navigation item to run. The method certainly highlights the item in the navigation drawer, or 'checks' it, but it does not seem to call the OnNavigationItemSelectedListener resulting in a blank screen on start-up if your start-up screen depends on navigation drawer selections. It is possible to manually call the listener, but it seems hacky:

if (savedInstanceState == null) this.onNavigationItemSelected(navigationView.getMenu().getItem(0));

The above code assumes:

  1. You have implemented NavigationView.OnNavigationItemSelectedListener in your activity
  2. You have already called:
    navigationView.setNavigationItemSelectedListener(this);
  3. The item you wish to select is located in position 0



回答8:


You have to call 2 functions for this:

First: for excuting the commands you have implemented in onNavigationItemSelected listener:

onNavigationItemSelected(navigationView.getMenu().getItem(R.id.nav_camera));

Second: for changing the state of the navigation drawer menu item to selected (or checked):

navigationView.setCheckedItem(R.id.nav_camera);

I called both functions and it worked for me.




回答9:


Following code will only make menu item selected:

navigationView.setCheckedItem(id);

To select and open the menu item, add following code after the above line.

onNavigationItemSelected(navigationView.getMenu().getItem(0));




回答10:


This is my solution, very simple.

Here is my menu.xml file:

<group
    android:id="@+id/grp1"
    android:checkableBehavior="single">
    <item
        android:id="@+id/nav_all_deals"
        android:checked="true"
        android:icon="@drawable/ic_all_deals"
        android:title="@string/all_deals" />
    <item
        android:id="@+id/nav_news_and_events"
        android:icon="@drawable/ic_news"
        android:title="@string/news_and_events" />
    <item
        android:id="@+id/nav_histories"
        android:icon="@drawable/ic_histories"
        android:title="@string/histories" />
</group>

Above menu will highlight the first menu item. Below line will do something(eg: show the first fragment, etc). NOTE: write after 'configure your drawer code'

onNavigationItemSelected(mNavigationView.getMenu().getItem(0));



回答11:


Easiest way is to select it from xml as follows,

<menu>
   <group android:checkableBehavior="single">
         <item
              android:checked="true"
              android:id="@+id/nav_home"
              android:icon="@drawable/nav_home"
              android:title="@string/main_screen_title_home" />

Note the line android:checked="true"




回答12:


First of all create colors for selected item. Here https://stackoverflow.com/a/30594875/1462969 good example. It helps you to change color of icon. For changing background of all selected item add in your values\style.xml file this 

  <item name="selectableItemBackground">@drawable/selectable_item_background</item>

Where selectable_item_background should be declared in drawable/selectable_item_background.xml 

  <?xml version="1.0" encoding="utf-8"?>
    <selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@color/accent_translucent"
      android:state_pressed="true" />
    <item android:drawable="@android:color/transparent" />
   </selector>

Where color can be declared in style.xml

 <color name="accent_translucent">#80FFEB3B</color>

And after this 

   // The main navigation menu with user-specific actions
        mainNavigationMenu_ = (NavigationView) findViewById(R.id.main_drawer);
        mainNavigationMenu_.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(MenuItem menuItem) {
                mainNavigationMenu_.getMenu().findItem(itemId).setChecked(true);
                return true;
            }
        });

As you see I used this mainNavigationMenu_.getMenu().findItem(itemId).setChecked(true); to set selected item. Here navigationView

 <android.support.design.widget.NavigationView
        android:id="@+id/main_drawer"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:headerLayout="@layout/header_main_navigation_menu"
        app:itemIconTint="@color/state_list"
        app:itemTextColor="@color/primary"
        app:menu="@menu/main_menu_drawer"/>



回答13:


When using BottomNavigationView the other answers such as navigationView.getMenu().getItem(0).setChecked(true); and navigationView.setCheckedItem(id); won't work calling setSelectedItemId works:

    BottomNavigationView bottomNavigationView = findViewById(R.id.bottom_navigation_view);

    bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
            // TODO: 10-Aug-19 your code here 
        }
    });

    bottomNavigationView.setSelectedItemId(R.id.myitem);



回答14:


Make a selector for Individaual item of Nav Drawer

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@color/darkBlue" android:state_pressed="true"/>
    <item android:drawable="@color/darkBlue" android:state_checked="true"/>
    <item android:drawable="@color/textBlue" />
</selector>

Make a few changes in your NavigationView

<android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:itemBackground="@drawable/drawer_item"
        android:background="@color/textBlue"
        app:itemIconTint="@color/white"
        app:itemTextColor="@color/white"
        app:menu="@menu/activity_main_drawer"
        />



回答15:


on your activity(behind the drawer):

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
            this, drawer, toolbar,
               R.string.navigation_drawer_open,
               R.string.navigation_drawer_close);
    drawer.addDrawerListener(toggle);
    toggle.syncState();

    NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);
    navigationView.setCheckedItem(R.id.nav_portfolio);
    onNavigationItemSelected(navigationView.getMenu().getItem(0));
}

and 

@Override
public boolean onNavigationItemSelected(MenuItem item) {
    // Handle navigation view item clicks here.
    int id = item.getItemId();

    Fragment fragment = null;

    if (id == R.id.nav_test1) {
        fragment = new Test1Fragment();
        displaySelectedFragment(fragment);
    } else if (id == R.id.nav_test2) {
        fragment = new Test2Fragment();
        displaySelectedFragment(fragment);
    }

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    drawer.closeDrawer(GravityCompat.START);
    return true;
}

and in your menu:

<group android:checkableBehavior="single">

    <item
        android:id="@+id/nav_test1"
        android:title="@string/test1" />

    <item
        android:id="@+id/nav_test2"
        android:title="@string/test2" />

  </group>

so first menu is highlight and show as default menu.




回答16:


Below code is used to selected the first item and highlight the selected first item in the menu.

onNavigationItemSelected(mNavigationView.getMenu().getItem(0).setChecked(true));



回答17:


For some reason it's preferable to find the MenuItem using the ID's.

drawer.getMenu().findItem(R.id.action_something).setChecked(true);


来源：https://stackoverflow.com/questions/31233279/navigation-drawer-how-do-i-set-the-selected-item-at-startup

标签
android
navigation-drawer
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