Navigation drawer: How do I set the selected item

2019-01-03 08:04发布

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.

16条回答
可以哭但决不认输i
2楼-- · 2019-01-03 08:31

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
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小情绪 Triste *
3楼-- · 2019-01-03 08:33

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"

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SAY GOODBYE
4楼-- · 2019-01-03 08:34

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

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该账号已被封号
5楼-- · 2019-01-03 08:36

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"/>
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贼婆χ
6楼-- · 2019-01-03 08:38

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));
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放我归山
7楼-- · 2019-01-03 08:40

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.

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