按下工具栏中的汉堡包图标时，导航抽屉无法打开

Question

I am trying to toggle the navigation view by the hamburger icon. The navigation view is appearing on sliding from the left. The following is the code that I have included in my MainActivity "onCreate Function"

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        toolbar.setVisibility(View.VISIBLE);
        setSupportActionBar(toolbar);

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);

        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);

        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, mDrawerLayout, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        mDrawerLayout.addDrawerListener(toggle);
        getSupportActionBar().setHomeButtonEnabled(true);
        toggle.syncState();

I also have tried this code block which doesn't seem to work.

    @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_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

I also tried this

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                mDrawerLayout = findViewById(R.id.drawer_layout);
                mDrawerLayout.openDrawer(GravityCompat.START);  // OPEN DRAWER
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

My main_activity.xml is this

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">
    >

    <RelativeLayout 
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:id="@+id/activity_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <include
        layout="@layout/app_bar_main"
        android:layout_height="match_parent"
        android:layout_width="match_parent" />
        <android.support.design.widget.BottomNavigationView
            android:id="@+id/bottom_navigation"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            app:itemBackground="@color/colorPrimary"
            app:itemIconTint="@drawable/bottom_navigation_bar"
            app:itemTextColor="@drawable/bottom_navigation_bar"
            app:menu="@menu/my_navigation_items" />

        <android.support.v4.view.ViewPager
            android:id="@+id/viewpager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_above="@+id/bottom_navigation"
            android:layout_alignParentTop="true"
            app:layout_behavior="@string/appbar_scrolling_view_behavior" />

    </RelativeLayout>

    <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:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />



</android.support.v4.widget.DrawerLayout>

This is my app_bar_main.xml which is where I define the ui of toolbar.

    enter code here

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.example.android.moodindigo.MainActivity">

    <!--<RelativeLayout-->
    <!--android:id="@+id/relativelayout_for_fragment"-->
    <!--android:layout_width="match_parent"-->
    <!--android:layout_height="match_parent"-->
    <!--&gt;</RelativeLayout>-->

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay"
            app:title="Mood Indigo"
            />

    </android.support.design.widget.AppBarLayout>

    <!--<include layout="@layout/content_main" />-->

</android.support.design.widget.CoordinatorLayout>

Any help would be highly appreciated. I don't know what I am doing wrong. Please let me know if anything else is needed. I didn't paste the whole code here as the project is quite big. I checked many StackOverflow post for this and I tried to do the same thing but it doesn't seem to work.

Answer 1

try this in the onCreate of your main activity :

 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.setDrawerListener(toggle);
    toggle.syncState();

i hope it will help you!

Answer 2

In your ActionBarDrawerToggle constructor you use toolbar as third parameter. I am not sure if it is valid, since the official documentation for ActionBarDrawerToggle constructor parameters quotes:

Parameters:

activity - Activity: the Activity hosting the drawer

drawerLayout - Drawerlayout: the DrawerLayout to link to the given Activity's ActionBar

drawerImageRes - int: A Drawable resource to use as the drawer indicator

openDrawerContentDescRes - int: A String resource to describe the "open drawer" action for accessibility

closeDrawerContentDescRes - int: A String resource to describe the "close drawer" action for accessibility

So, the third parameter should be Drawable Resource but toolbar is a View.

Edit: As you are using v7 and not v4, there is one sentence from official documentation https://developer.android.com/reference/android/support/v7/app/ActionBarDrawerToggle.html I think is important:

Please use ActionBarDrawerToggle(Activity, DrawerLayout, int, int) if you are setting the Toolbar as the ActionBar of your activity.

So it seems you should use differnt constructor from the one you are using now.

Hope this will help.