Question

我如何做到这一点，所以当我单击菜单时它会执行某些操作（在这种情况下，请写“ click”）？由于某种原因，它不起作用。我关注了一个youtube视频，这是android studio的新手。先感谢您。另外，我该如何绕过这个“大部分是代码”错误。当我没有更多的解释。

    DrawerLayout drawerLayout;
    ActionBarDrawerToggle drawerToggle;
    Toolbar toolbar;
    NavigationView navigationView;
    private DrawerLayout mDrawerLayout;


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

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


    drawerLayout = findViewById(R.id.drawer);
    drawerToggle = new ActionBarDrawerToggle(this,drawerLayout,toolbar,R.string.open_drawer,R.string.close_drawer);
    drawerLayout.addDrawerListener(drawerToggle);
    drawerToggle.setDrawerIndicatorEnabled(true);
    drawerToggle.syncState();

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


}

OnClick部分

@Override
    public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
        switch (menuItem.getItemId())
        {
            case R.id.nav_new_purchase:

                Toast.makeText(this,"CLICK",Toast.LENGTH_LONG).show();
                break;

            case R.id.nav_active_purchase:
                //TODO

            case R.id.nav_old_purchase:
                //TODO
        }
        return false;
    }

带有（main_activity.xml）的XML文件

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.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=".MainActivity"
    android:id="@+id/drawer">

    <include

        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        layout="@layout/app_toolbar"/>
    <com.google.android.material.navigation.NavigationView
        android:id="@+id/navigationView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:headerLayout="@layout/drawer_header"
        app:menu="@menu/drawer_menu"
        android:layout_gravity="start">

    </com.google.android.material.navigation.NavigationView>

    <androidx.constraintlayout.widget.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <com.google.android.material.floatingactionbutton.FloatingActionButton
            android:id="@+id/add_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:foreground="@drawable/ic_action_add"
            app:backgroundTint="#00FF00"
            app:fabCustomSize="200dp"
            app:fabSize="auto"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <TextView
            android:id="@+id/textView_add"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginBottom="100dp"
            android:text="@string/add"
            android:textSize="24sp"
            android:textStyle="bold"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/add_button" />
    </androidx.constraintlayout.widget.ConstraintLayout>

</androidx.drawerlayout.widget.DrawerLayout>

Answer 1

您检查了以下内容：

@Override
    public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
        //add this line
        Toast.makeText(this,"WORK",Toast.LENGTH_LONG).show();
        switch (menuItem.getItemId())
        {
            case R.id.nav_new_purchase:

                Toast.makeText(this,"nav_new_purchase",Toast.LENGTH_LONG).show();
                break;

            case R.id.nav_active_purchase:
                Toast.makeText(this,"nav_new_purchase",Toast.LENGTH_LONG).show();
                break;

            case R.id.nav_old_purchase:
                Toast.makeText(this,"nav_new_purchase",Toast.LENGTH_LONG).show();
                break;
            default:
                Toast.makeText(this,"Not found menu id",Toast.LENGTH_LONG).show();
                break;
        }
        return false;
    }

如果显示“ WORK”，则表示您对工作进行编码。此外，还会显示单击的ID或“找不到菜单ID”。如果将显示“未找到菜单ID”，则您检查了错误的菜单ID。

Answer 2

drawerLayout.closeDrawer（GravityCompat.START）在最后一行单击侦听器中添加此代码

每当我单击导航抽屉时，它就会关闭

2 个答案: