错误的第二个参数类型。发现:';android.app.Fragment';,必填项:';android.support.v4.app.Fragment';
我正在Youtube上看教程视频。我从一开始就做了两次同样的事情,但仍然结巴。我会继续犯这个错误,但他不会犯错误 代码在这里。下面是私有void DisplayFragment类下的错误错误的第二个参数类型。发现:';android.app.Fragment';,必填项:';android.support.v4.app.Fragment';,android,android-fragments,types,arguments,required,Android,Android Fragments,Types,Arguments,Required,我正在Youtube上看教程视频。我从一开始就做了两次同样的事情,但仍然结巴。我会继续犯这个错误,但他不会犯错误 代码在这里。下面是私有void DisplayFragment类下的错误 package com.example.kenpachi.navigation_drawer; import android.app.Fragment; import android.app.FragmentTransaction; import android.os.Bundle; import a
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
中)给出错误的一行:
ft.replace(R.id.MyFrameLayout, fragment);
谢谢。如果这里有人感兴趣,请看我要做的视频指南:替换
import android.app.Fragment;
与
android有两种类型的片段
import android.app.Fragment
则必须在活动中使用import android.app.Fragment
或
在FragmentOne中,使用导入android.support.v4.app.Fragment
则必须在活动中使用导入android.support.v4.app.Fragment
片段创建和片段调用必须是同一类型的谢谢大家。当我切换时
“导入android.app.Fragment;”
到“android.support.v4.app.Fragment;”
对于MainActivity和Fragment一二三,问题消失了。
我以前只在MainActivity中执行此操作,因此我将收到新错误。
再次感谢。删除导入android.app.Fragment;并将导入android.support.v4.app.Fragment;
import android.support.v4.app.Fragment;