導航抽屜打開一個新的片段

Question

我用導航抽屜活動打開一個新的Android Studio項目。因此，layout-folder和Java-Class MainActivity中有activty_main.xml，app_bar_main.xml，content_main.xml和nav_header_main.xml。

當使用Navigation Drawer中的項目時，應該打開一個新的片段。在片段中也必須是導航抽屜。我如何可以使用API​​ 8.我該怎麼做？如何打開一個新的片段？

activity_main：

<?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" /> 

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

    <FrameLayout 
     android:id="@+id/content_frame" 
     android:layout_width="match_parent" 
     android:layout_height="0dp" 
     android:layout_weight="1" /> 
</LinearLayout> 

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

MainAcitvity：

package de.computerfreak.app.test; 

import android.app.Fragment; 
import android.app.FragmentTransaction; 
import android.os.Bundle; 
import android.support.design.widget.FloatingActionButton; 
import android.support.design.widget.Snackbar; 
import android.view.View; 
import android.support.design.widget.NavigationView; 
import android.support.v4.view.GravityCompat; 
import android.support.v4.widget.DrawerLayout; 
import android.support.v7.app.ActionBarDrawerToggle; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.view.Menu; 
import android.view.MenuItem; 

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(); 
    Fragment newFragment; 
    FragmentTransaction transaction = getFragmentManager().beginTransaction(); 

    if (id == R.id.nav_camara) { 
     // Handle the camera action 
     newFragment = new f1(); 
     transaction.replace(R.id.content_frame, newFragment); 
     transaction.addToBackStack(null); 
     transaction.commit(); 
    } else if (id == R.id.nav_gallery) { 

    } else if (id == R.id.nav_slideshow) { 

    } else if (id == R.id.nav_manage) { 

    } else if (id == R.id.nav_share) { 

    } else if (id == R.id.nav_send) { 

    } 

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

對不起，我的英語和感謝您的幫助！

Answer 1

這裏是我是如何實現這在我自己的解決方案之一，只需切換酌情值：

mNavigationView = (NavigationView) (findViewById(R.id.nav_menu)); 
    mNavigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() { 
     @Override 
     public boolean onNavigationItemSelected(MenuItem item) { 
      switch(item.getItemId()) 
      { 
       case R.id.menuEvents: 
       { 
        mFragmentTransaction = getSupportFragmentManager().beginTransaction(); 
        mFragmentTransaction.replace(R.id.main_fragment, new eventFragment()); 
        mFragmentTransaction.commit(); 
        getSupportActionBar().setTitle("Upcoming Events"); 
        //item.setChecked(true); 
        mDrawerLayout.closeDrawers(); 
        break; 
       } 

       case R.id.menuTechnique: 
       { 
        mFragmentTransaction = getSupportFragmentManager().beginTransaction(); 
        mFragmentTransaction.replace(R.id.main_fragment, new techniqueFragment()); 
        mFragmentTransaction.commit(); 
        getSupportActionBar().setTitle("Useful Techniques"); 
        //item.setChecked(true); 
        mDrawerLayout.closeDrawers(); 
        break; 
       } 

       case R.id.menuLink: 
       { 
        mFragmentTransaction = getSupportFragmentManager().beginTransaction(); 
        mFragmentTransaction.replace(R.id.main_fragment, new linkFragment()); 
        mFragmentTransaction.commit(); 
        getSupportActionBar().setTitle("Helpful Links"); 
        //item.setChecked(true); 
        mDrawerLayout.closeDrawers(); 
        break; 
       } 

       case R.id.menuSettings: 
       { 
        mFragmentTransaction = getSupportFragmentManager().beginTransaction(); 
        mFragmentTransaction.replace(R.id.main_fragment, new settingFragment()); 
        mFragmentTransaction.commit(); 
        getSupportActionBar().setTitle("Settings"); 
        //item.setChecked(true); 
        mDrawerLayout.closeDrawers(); 
        break; 
       } 
      } 
      return true; 
     } 
    });