xmlns:app=“http://schemas.android.com/apk/res-auto”
xmlns:tools=“http://schemas.android.com/tools”
android:id=“@+id/drawerLayout”
android:layout_width=“match_parent”
android:layout_height=“match_parent”
tools:context=“.MainActivity”>
android:layout_width=“match_parent” android:layout_height=“match_parent”> android:id=“@+id/toolbar” android:background=“#969C99” android:layout_width=“match_parent” android:layout_height=“wrap_content”/> android:id=“@+id/fab” android:layout_width=“wrap_content” android:layout_height=“wrap_content” android:layout_gravity=“bottom|end” android:layout_margin=“16dp” android:src=“@drawable/yes” app:elevation=“8dp” />
android:id=“@+id/navView” android:layout_width=“match_parent” android:layout_height=“match_parent” android:layout_gravity=“start” app:menu=“@menu/nav_menu” app:headerLayout=“@layout/nav_header”/> import androidx.annotation.NonNull; import androidx.appcompat.app.ActionBar; import androidx.appcompat.app.AppCompatActivity; import androidx.appcompat.widget.Toolbar; import androidx.core.view.GravityCompat; import androidx.drawerlayout.widget.DrawerLayout; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Toast; import com.google.android.material.floatingactionbutton.FloatingActionButton; import com.google.android.material.navigation.NavigationView; import com.google.android.material.snackbar.Snackbar; /** */ public class MainActivity extends AppCompatActivity { private DrawerLayout mDrawerLayout; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Toolbar toolbar=findViewById(R.id.toolbar); setSupportActionBar(toolbar); mDrawerLayout=findViewById(R.id.drawerLayout); NavigationView navigationView=findViewById(R.id.navView); FloatingActionButton fab=findViewById(R.id.fab);//悬浮按钮 fab.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //可交互提示 Snackbar.make(v,“删除”,Snackbar.LENGTH_SHORT) .setAction(“取消”, new View.OnClickListener() { @Override public void onClick(View v) { Toast.makeText(MainActivity.this,“已取消”,Toast.LENGTH_SHORT).show(); } }).show(); } }); ActionBar actionBar=getSupportActionBar(); if (actionBar!=null){ actionBar.setDisplayHomeAsUpEnabled(true); actionBar.setHomeAsUpIndicator(R.drawable.menu); } // navigationView.setCheckedItem(R.id.navCall);//默认选中 navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() { @Override public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) { switch (menuItem.getItemId()){ case R.id.navCall: Toast.makeText(MainActivity.this,“电话”,Toast.LENGTH_SHORT).show(); break; case R.id.navFriends: Toast.makeText(MainActivity.this,“朋友”,Toast.LENGTH_SHORT).show(); break; case R.id.navLocation: Toast.makeText(MainActivity.this,“地址”,Toast.LENGTH_SHORT).show(); break; case R.id.nav_email: Toast.makeText(MainActivity.this,“邮箱”,Toast.LENGTH_SHORT).show(); break; case R.id.navTask: Toast.makeText(MainActivity.this,“任务”,Toast.LENGTH_SHORT).show(); break; } mDrawerLayout.closeDrawers(); return true; } }); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.toolbar,menu); return true; } @Override public boolean onOptionsItemSelected(@NonNull MenuItem item) {4.修改MainActivity.java