错误的第二个参数类型。发现：'android.app.Fragment'，必需：'android.support.v4.app.Fragment'

-1

我正在看Youtube上的教程视频。我从一开始就兴奋地做了同样的事情，但仍然在那里。我会不断收到这个错误，但他没有收到错误。错误的第二个参数类型。发现：'android.app.Fragment'，必需：'android.support.v4.app.Fragment'

代码在这里。错误在private void DisplayFragment类下面。

package com.example.kenpachi.navigation_drawer; 

import android.app.Fragment; 
import android.app.FragmentTransaction; 
import android.os.Bundle; 
import android.support.design.widget.FloatingActionButton; 
import android.support.design.widget.NavigationView; 
import android.support.design.widget.Snackbar; 
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; 
import android.view.View; 


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); 
} 


private void DisplayFragment(int id) { 

    Fragment fragment = null; 
    switch (id) { 
     case R.id.nav_one: 
      fragment = new FragmentOne(); 
      break; 
     case R.id.nav_two: 
      fragment = new FragmentTwo(); 
      break; 
     case R.id.nav_three: 
      fragment = new FragmentThree(); 
    } 

    if (fragment != null) { 

     android.support.v4.app.FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); 

     ft.replace(R.id.MyFrameLayout, fragment); // "fragment" gives me this error. 

     ft.commit(); 
    } 
} 


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

    if (id == R.id.nav_camera) { 
     // Handle the camera action 
    } 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; 
} 
}

这是（在DisplayFragment）的线，让我的错误：

ft.replace(R.id.MyFrameLayout, fragment);

感谢。如果有人感兴趣这里是视频指南即时试图做的事：https://youtu.be/iZ8Y7W2jbv8?t=386

来源

2017-09-16 İbrahim K.

remove import android.app.Fragment;并把导入android.support.v4.app.Fragment; –

机器人有两种类型的片段

android.app的。片段
android.support.v4.ap p.Fragment

所以你必须检查你的FragmentOne，FragmentTwo ..你使用...

为例FragmentOne内其中键入您的使用import android.app.Fragment那么你必须在你的活动中使用import android.app.Fragment。

FragmentOne内

或

您使用import android.support.v4.app.Fragment那么你必须在你的活动中使用import android.support.v4.app.Fragment。

片段创建和片段调用都是必须在同一类型

来源

2017-09-16 07:39:59 Raja

更换

import android.app.Fragment;

与

import android.support.v4.app.Fragment;

来源

2017-09-16 07:35:06 fida1989

谢谢你们。当我切换
"import android.app.Fragment;"到"android.support.v4.app.Fragment;"
对于MainActivity和FragmentOne-Two-Three问题没有了。
我之前只为MainActivity做过，所以我会得到新的错误。
再次感谢。

来源

2017-09-16 07:51:42

错误的第二个参数类型。发现：'android.app.Fragment'，必需：'android.support.v4.app.Fragment'

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