java - 使用fragment在Activity中创建新的Activity

Question

我正在尝试在 SecondFragment 类中添加新 Activity ，所以我所做的就是在 secondary_layout.xml 中添加按钮

<Button
    android:layout_width="match_parent"
    android:layout_height="125dp"
    android:text="Today&apos;s Special"
    android:id="@+id/button"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="false" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="125dp"
    android:text="Appetizers"
    android:id="@+id/button2"
    android:layout_below="@+id/button"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true"
    android:onClick="Go to the Dessert Page"/>

<Button
    android:layout_width="wrap_content"
    android:layout_height="125dp"
    android:text="Salads"
    android:id="@+id/button3"
    android:layout_below="@+id/button2"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="125dp"
    android:text="Dessert"
    android:id="@+id/button4"
    android:layout_below="@+id/button3"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true" />

单击开胃菜按钮后，我想使用开胃菜页面打开一个新 Activity 。

我想将其全部设置在我的 SecondFragment 类中

  public class SecondFragment extends Fragment
  {
    View myView;
     @Nullable
     @Override
     public View onCreateView
     (LayoutInflater inflater, ViewGroup container,      
      Bundle  savedInstanceState)
      {
      myView = inflater.inflate(R.layout.second_layout, container, false);
      return myView;
  }
    }

这是我的主要 Activity 类

  public class MainActivity extends 
   AppCompatActivity implements            
   NavigationView.OnNavigationItemSelectedListener
   {
   @Override
      protected void onCreate(Bundle savedInstanceState)
    {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

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

       FloatingActionButton fab =  
      (FloatingActionButton)   findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });

    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();

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

@Override
public void onBackPressed() {
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawer(GravityCompat.START);
    } else {
        super.onBackPressed();
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@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);
}

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

    if (id == R.id.nav_first_layout)
    {
        fragmentManager.beginTransaction()
                .replace(R.id.content_frame
                        , new FirstFragment())
                .commit();
        // Handle the camera action
    }
    else if (id == R.id.nav_second_layout)
    {
        fragmentManager.beginTransaction()
                .replace(R.id.content_frame
                        , new SecondFragment())
                .commit();

    }
    else if (id == R.id.nav_third_layout)
    {
        fragmentManager.beginTransaction()
                .replace(R.id.content_frame
                        , new ThirdFragment())
                .commit();

    }
    else if (id == R.id.nav_fourth_layout)
    {
        fragmentManager.beginTransaction()
                .replace(R.id.content_frame
                        , new FourthFragment())
                .commit();
    }
    else if (id == R.id.nav_fifth_layout)
    {
            fragmentManager.beginTransaction()
                    .replace(R.id.content_frame
                            , new FifthFragment())
                    .commit();
    }

    else if (id == R.id.button)
    {
        fragmentManager.beginTransaction()
                .replace(R.id.content_frame
                        , new FifthFragment())
                .commit();
    }

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

请任何人都可以帮助我在 SecondFragment 类中添加一个新 Activity ，以在 Appetizer 类中打开一个新 Activity 并向他们展示图片示例

Answer 1

在按钮的 onClick 上尝试一下

Intent intent = new Intent(getActivity(), Appetizer.class);
startActivity(intent);