如何将代码分配给抽屉按钮？

Question

我希望在单击导航菜单中的按钮以启动新活动时。使用当前代码，单击按钮时不会发生任何事情。我是 Android 新手，所以如果我不理解您的代码并提出一些问题，请不要生气。

这是我的 navigation_menu.xml：

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/nav_account"
    android:title="Home"
    android:icon="@mipmap/ic_home_black_24dp">
</item>
<item android:id="@+id/nav_delete"
    android:title="Delete Boards"
    android:icon="@mipmap/ic_close_black_24dp">
</item>
<item android:id="@+id/nav_settings"
    android:title="Settings"
    android:icon="@mipmap/ic_settings_black_24dp">
</item>

这是我的 ma​​inActivity.java 抽屉代码：

 mDrawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
    mToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.string.open, R.string.close);

 mDrawerLayout.addDrawerListener(mToggle);
    mToggle.syncState();

 @Override
public boolean onOptionsItemSelected(MenuItem item) {

    if (mToggle.onOptionsItemSelected(item)){

        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.nav_delete) {
            //call new activity
        }
}

    return super.onOptionsItemSelected(item);
}

}

MainActivity.xml 代码：

<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.studios.cookie.chanomatic.MainActivity"
android:id="@+id/drawerLayout">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView3"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="0.02"
        android:text="Boards"
        android:textAlignment="center"
        android:textColor="@android:color/black" />
</LinearLayout>
<android.support.design.widget.NavigationView
android:id = "@+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
app:menu="@menu/navigation_menu"
android:layout_gravity="start">
</android.support.design.widget.NavigationView>
</android.support.v4.widget.DrawerLayout>

Answer 1

在您的onCreate 方法中添加以下代码：

    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);

在你的 mainactivity 类中实现列表器：

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener

而XML文件是这样的：

<?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">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <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>

然后在你的 onNavigationItemSelected 方法中看起来像这样：

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

        if (id == R.id.nav_delete) {
        //call new activity
         }

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

希望对你有帮助

Answer 2

你给导航菜单充气了吗？ 如果没有，请确保您的导航菜单位于 res/menu 文件夹中，然后添加：

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

Answer 3

试试这个：

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

        if (id == R.id.nav_account)
        {
              //your intent
        }

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

在主活动中实现导航菜单的监听器。

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener

在活动中找到导航视图引用并设置监听器。

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

完整代码：

mDrawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
mToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.string.open, R.string.close);

mDrawerLayout.addDrawerListener(mToggle);
mToggle.syncState();
navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);

XML 文件：

<?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">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <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:itemIconTint="@drawable/drawer_icon"
        app:itemBackground="@drawable/drawer_text_background"
        app:itemTextColor="@drawable/drawer_text"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />

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