Question

从MainActivity，我实例化一个这样的简单片段：

Fragment fragment = new RentFragment();

RentFragment.java是这样的：

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class RentFragment extends Fragment {

    public RentFragment(){} 
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_rent, container, false);

        return rootView;
    }

}

fragment_rent.xml是这样的：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/txtLabel"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="Rent"
        android:textSize="16dp" />

    <fragment android:name="com.example.android.fragments.HeadlinesFragment"
              android:id="@+id/headlines_fragment"
              android:layout_weight="1"
              android:layout_width="0dp"
              android:layout_height="match_parent" />
</RelativeLayout>

错误日志是这样的：

09-16 13:32:32.759: E/AndroidRuntime(9131): FATAL EXCEPTION: main
09-16 13:32:32.759: E/AndroidRuntime(9131): android.view.InflateException: Binary XML file line #14: Error inflating class fragment
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at com.example.devicerentalsystem.RentFragment.onCreateView(RentFragment.java:15)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.Fragment.performCreateView(Fragment.java:1695)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.BackStackRecord.run(BackStackRecord.java:682)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.os.Handler.handleCallback(Handler.java:730)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.os.Handler.dispatchMessage(Handler.java:92)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.os.Looper.loop(Looper.java:137)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.ActivityThread.main(ActivityThread.java:5103)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at java.lang.reflect.Method.invokeNative(Native Method)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at java.lang.reflect.Method.invoke(Method.java:525)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at dalvik.system.NativeStart.main(Native Method)
09-16 13:32:32.759: E/AndroidRuntime(9131): Caused by: android.app.Fragment$InstantiationException: Unable to instantiate fragment com.example.android.fragments.HeadlinesFragment: make sure class name exists, is public, and has an empty constructor that is public
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.Fragment.instantiate(Fragment.java:592)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.Fragment.instantiate(Fragment.java:560)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at  android.app.Activity.onCreateView(Activity.java:4738)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
09-16 13:32:32.759: E/AndroidRuntime(9131):     ... 19 more
09-16 13:32:32.759: E/AndroidRuntime(9131): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.android.fragments.HeadlinesFragment" on path: DexPathList[[zip file "/data/app/com.example.devicerentalsystem-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.devicerentalsystem-1, /vendor/lib, /system/lib]]
 09-16 13:32:32.759: E/AndroidRuntime(9131):    at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
 09-16 13:32:32.759: E/AndroidRuntime(9131):    at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
09-16 13:32:32.759: E/AndroidRuntime(9131):     at android.app.Fragment.instantiate(Fragment.java:582)
09-16 13:32:32.759: E/AndroidRuntime(9131):     ... 22 more

我做错了什么？提前谢谢。

Answer 1

我想我发现了问题所在。片段不能容纳另一个片段。所以我在xml中添加了一个framelayout，并使用片段管理器将其替换为我自己的片段。

感谢大家的帮助。

XML：

    <!-- Framelayout to display Fragments -->
    <FrameLayout
        android:id="@+id/sample"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />


    <Button
        android:id="@+id/scan"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:onClick="scanAgain"
        android:text="Re-Scan" />

</RelativeLayout>

更改java：

View rootView = inflater.inflate(R.layout.fragment_add, container, false);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.sample, (Fragment)headlineFrag).commit();

android.view.InflateException：错误膨胀片段

1 个答案: