在導航抽屜中添加Google地圖活動時出錯（材質設計）

Question

我正在使用Google地圖活動在我的Android應用程序中實現材質設計，當我嘗試在導航中添加Google地圖活動時，應用程序顯示錯誤「不兼容的類型 - 必需：android.support.v4.app.Fragment」。 這裏是我的mainactivity.java

import android.os.Bundle; 
import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.support.v4.app.FragmentTransaction; 
import android.support.v4.widget.DrawerLayout; 
import android.support.v7.app.ActionBarActivity; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.webkit.WebView; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.Toast; 

import info.androidhive.materialdesign.R; 


public class MainActivity extends AppCompatActivity implements FragmentDrawer.FragmentDrawerListener { 
    private WebView myWebView; 
    private static String TAG = MainActivity.class.getSimpleName(); 


    private Toolbar mToolbar; 
    private FragmentDrawer drawerFragment; 



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

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

     setSupportActionBar(mToolbar); 
     getSupportActionBar().setDisplayShowHomeEnabled(true); 


     drawerFragment = (FragmentDrawer) 
       getSupportFragmentManager().findFragmentById(R.id.fragment_navigation_drawer); 
     drawerFragment.setUp(R.id.fragment_navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout), mToolbar); 
     drawerFragment.setDrawerListener(this); 




     // display the first navigation drawer view on app launch 
     displayView(0); 
    } 


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


     if (id == R.id.action_settings) { 
      return true; 
     } 

     if(id == R.id.action_search){ 
      Toast.makeText(getApplicationContext(), "Search action is selected!", Toast.LENGTH_SHORT).show(); 
      return true; 
     } 

     return super.onOptionsItemSelected(item); 
    } 

    @Override 
    public void onDrawerItemSelected(View view, int position) { 
     displayView(position); 
    } 

    private void displayView(int position) { 
     Fragment fragment = null; 
     String title = getString(R.string.app_name); 
     switch (position) { 
      case 0: 
       fragment = new HomeFragment(); 
       title = getString(R.string.title_home); 
       break; 

      case 1: 
       fragment = new FriendsFragment(); 
       title = getString(R.string.title_friends); 
       break; 
      case 2: 
       fragment = new MessagesFragment(); 
       title = getString(R.string.title_messages); 
       break; 
      case 3: 
       fragment = new ContactFragment(); 
       title = getString(R.string.title_contact); 
       break; 
      case 4: 
       fragment=new HospitalMapsActivity(); 
       title = "Detect Hospital"; 
       break; 
      default: 
       break; 
     } 

     if (fragment != null) { 
      FragmentManager fragmentManager = getSupportFragmentManager(); 
      FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); 
      fragmentTransaction.replace(R.id.container_body, fragment); 
      fragmentTransaction.commit(); 

      // set the toolbar title 
      getSupportActionBar().setTitle(title); 
     } 
    } 
} 

Answer 1

我還沒有看到你的具體implementatios，但我認爲這個類的一個（或全部）android.app.Fragment，而不是android.support.v4.app.Fragment：HomeFragment，FriendsFragment，MessagesFragment或ContactFragment。

要解決您的問題，您的碎片必須extends android.support.v4.app.Fragment