在下一个代码中：
import android.support.v4.app.Fragment;
import android.content.res.Configuration;
import android.support.design.widget.NavigationView;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.DialogFragment;
import android.support.v7.app.ActionBar;
import android.app.Activity;
import android.os.Bundle;
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.view.Menu;
import android.view.MenuItem;
import android.support.v7.widget.Toolbar;
public class MainActivity extends AppCompatActivity {
private DrawerLayout mDrawer;
private Toolbar toolbar;
private DrawerLayout dlDrawer;
private ActionBarDrawerToggle drawerToggle;
private NavigationView nvDrawer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar=(Toolbar)findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mDrawer =(DrawerLayout)findViewById(R.id.drawer_layout);
dlDrawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawerToggle = setupDrawerToggle();
nvDrawer = (NavigationView) findViewById(R.id.nvView);
setupDrawerContent(nvDrawer);
final ActionBar ab=getSupportActionBar();
ab.setHomeAsUpIndicator(R.drawable.ic_one);
ab.setDefaultDisplayHomeAsUpEnabled(true);
dlDrawer.setDrawerListener(drawerToggle);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.drawer_view, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch(item.getItemId())
{
case R.id.home:
mDrawer.openDrawer(GravityCompat.START);
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
drawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
drawerToggle.onConfigurationChanged(newConfig);
}
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
selectDrawerItem(menuItem);
return true;
}
});
}
public void selectDrawerItem(MenuItem menuItem) {
Fragment fragment = null;
Class fragmentClass;
switch(menuItem.getItemId()) {
case R.id.nav_first_fragment:
fragmentClass = FirstFragment.class;
break;
case R.id.nav_second_fragment:
fragmentClass = SecondFragment.class;
break;
case R.id.nav_third_fragment:
fragmentClass = ThirdFragment.class;
break;
default:
fragmentClass = FirstFragment.class;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
menuItem.setChecked(true);
setTitle(menuItem.getTitle());
mDrawer.closeDrawers();
}
private ActionBarDrawerToggle setupDrawerToggle() {
return new ActionBarDrawerToggle(this, dlDrawer, toolbar, R.string.drawer_open, R.string.drawer_close);
}
}
App_main.xml文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/main_activity_appbar">
<include layout="@layout/app_bar"
android:id="@+id/app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"></include>
<android.support.v4.widget.DrawerLayout
android:id="@+id/drawer_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#E3F2FD"
android:id="@+id/main_container"
>
<fragment
android:id="@+id/nav_drawer"
android:name="askselva.com.sampematerial.NavigationDrawerFragment"
android:layout_width="280dp"
android:layout_height="match_parent"
android:layout_gravity="start"
tools:layout="@layout/fragment_navigation_drawer"></fragment>
</FrameLayout>
</android.support.v4.widget.DrawerLayout>
</LinearLayout>
错误
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: FATAL EXCEPTION: main
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: Process: askselva.com.sampematerial, PID: 18019
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{askselva.com.sampematerial/askselva.com.sampematerial.MainActivity}: android.view.InflateException: Binary XML file line #33: Error inflating class fragment
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2198)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.access$800(ActivityThread.java:139)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Looper.loop(Looper.java:136)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5086)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:132)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: Caused by: android.view.InflateException: Binary XML file line #33: Error inflating class fragment
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.invokeOriginalMethodNative(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.handleHookedMethod(XposedBridge.java:631)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:257)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at askselva.com.sampematerial.MainActivity.onCreate(MainActivity.java:26)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:5248)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.access$800(ActivityThread.java:139)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Looper.loop(Looper.java:136)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5086)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:132)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: Caused by: java.lang.NullPointerException
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at askselva.com.sampematerial.NavigationDrawerFragment.onCreateView(NavigationDrawerFragment.java:99)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.Fragment.performCreateView(Fragment.java:1965)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1047)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1237)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1339)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2295)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:111)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:314)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.BaseFragmentActivityHoneycomb.onCreateView(BaseFragmentActivityHoneycomb.java:31)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:79)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.invokeOriginalMethodNative(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.handleHookedMethod(XposedBridge.java:631)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:257)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at askselva.com.sampematerial.MainActivity.onCreate(MainActivity.java:26)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:5248)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.access$800(ActivityThread.java:139)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.os.Looper.loop(Looper.java:136)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5086)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:132)
11-05 00:30:33.925 18019-18019/askselva.com.sampematerial E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
这是我在LogCat中遇到的错误，我在如何解决这个错误中遇到错误。我应该如何在活动中使用片段。片段活动还是活动？我是Fragments的新手请帮助我.. 提前谢谢！
答案 0 :(得分：2)
getActivity（）在片段类中可用。由于你已经在你的活动中，只需删除对getActivity（）的调用。片段管理器的Ur代码将是
FragmentManager fragmentManager = getSupportFragmentManager();
此外，ur mainactivity应扩展FragmentActivity以获取支持片段管理器实例。即
public class MainActivity extends FragmentActivity {
此外，您需要先了解片段的基础知识，然后再继续。
查看此链接http://developer.android.com/guide/components/fragments.html了解详情。