我按照 http://www.techotopia.com/index.php/Using_Fragments_in_Android_-_A_Worked_Example 上的教程创建了一个应用程序, 但我有一个错误。

LogCat:

05-02 08:16:22.044: D/dalvikvm(1846): Late-enabling CheckJNI
05-02 08:16:22.080: D/AndroidRuntime(1846): Shutting down VM
05-02 08:16:22.080: W/dalvikvm(1846): threadid=1: thread exiting with uncaught exception (group=0xa4d81b20)
05-02 08:16:22.096: E/AndroidRuntime(1846): FATAL EXCEPTION: main
05-02 08:16:22.096: E/AndroidRuntime(1846): Process: com.example.myfragmentexample, PID: 1846
05-02 08:16:22.096: E/AndroidRuntime(1846): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.myfragmentexample/com.example.myfragmentexample.MainActivity}: android.view.InflateException: Binary XML file line #10: Error inflating class fragment
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.os.Handler.dispatchMessage(Handler.java:102)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.os.Looper.loop(Looper.java:136)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread.main(ActivityThread.java:5017)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at java.lang.reflect.Method.invokeNative(Native Method)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at java.lang.reflect.Method.invoke(Method.java:515)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at dalvik.system.NativeStart.main(Native Method)
05-02 08:16:22.096: E/AndroidRuntime(1846): Caused by: android.view.InflateException: Binary XML file line #10: Error inflating class fragment
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:290)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Activity.setContentView(Activity.java:1929)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at com.example.myfragmentexample.MainActivity.onCreate(MainActivity.java:12)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Activity.performCreate(Activity.java:5231)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
05-02 08:16:22.096: E/AndroidRuntime(1846):     ... 11 more
05-02 08:16:22.096: E/AndroidRuntime(1846): Caused by: android.app.Fragment$InstantiationException: Unable to instantiate fragment com.example.fragmentexample.ToolbarFragment: make sure class name exists, is public, and has an empty constructor that is public
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Fragment.instantiate(Fragment.java:597)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Fragment.instantiate(Fragment.java:561)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Activity.onCreateView(Activity.java:4778)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
05-02 08:16:22.096: E/AndroidRuntime(1846):     ... 21 more
05-02 08:16:22.096: E/AndroidRuntime(1846): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.fragmentexample.ToolbarFragment" on path: DexPathList[[zip file "/data/app/com.example.myfragmentexample-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.myfragmentexample-1, /system/lib]]
05-02 08:16:22.096: E/AndroidRuntime(1846):     at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at java.lang.ClassLoader.loadClass(ClassLoader.java:497)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at java.lang.ClassLoader.loadClass(ClassLoader.java:457)
05-02 08:16:22.096: E/AndroidRuntime(1846):     at android.app.Fragment.instantiate(Fragment.java:583)
05-02 08:16:22.096: E/AndroidRuntime(1846):     ... 24 more

MainActivity.java:

package com.example.myfragmentexample;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

public class MainActivity extends FragmentActivity implements
        ToolbarFragment.ToolbarListener {

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


    public void onButtononClick(int fontsize, String text) {
        TextFragment textfragment = (TextFragment) getSupportFragmentManager()
                .findFragmentById(R.id.text_fragment);
        textfragment.zmienWlasciwosci(fontsize, text);

    }

}

activity_main.xml:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <fragment
        android:id="@+id/toolbar_fragment"
        android:name="com.example.fragmentexample.ToolbarFragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        tools:layout="@layout/toolbar_fragment" />

    <fragment
        android:id="@+id/text_fragment"
        android:name="com.example.fragmentexample.TextFragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        tools:layout="@layout/text_fragment" />

</RelativeLayout>

ToolbarFragment.java:

package com.example.myfragmentexample;

import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;

public class ToolbarFragment extends Fragment implements
        OnSeekBarChangeListener {

    private static int seekvalue = 10;
    private static EditText edittext;

    ToolbarListener activityCallback;

    public interface ToolbarListener {
        public void onButtononClick(int position, String text);
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        try {
            activityCallback = (ToolbarListener) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString()
                    + " must implement ToolbarListener");
        }
    }

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

        View view = inflater.inflate(R.layout.toolbar_fragment, container,
                false);

        edittext = (EditText) view.findViewById(R.id.editText);
        SeekBar seekbar = (SeekBar) view.findViewById(R.id.seekBar);
        seekbar.setOnSeekBarChangeListener(this);
        Button button = (Button) view.findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                buttonClicked(v);

            }
        });

        return view;
    }

    public void buttonClicked(View view) {
        activityCallback.onButtononClick(seekvalue, edittext.getText()
                .toString());

    }

    @Override
    public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) {
        seekvalue = arg1;

    }

    @Override
    public void onStartTrackingTouch(SeekBar arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStopTrackingTouch(SeekBar arg0) {
        // TODO Auto-generated method stub

    }

}

toolbar_fragment.xml:

<?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" >

    <EditText 
        android:id="@+id/editText" 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="16dp"
        android:ems="10"
        android:inputType="text">
        <requestFocus />
    </EditText>

    <SeekBar
        android:id="@+id/seekBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/editText"
        android:layout_marginTop="14dp" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="17dp"
        android:layout_below="@+id/seekBar"
        android:text="@string/button_text" />

</RelativeLayout>

TextFragment.java:

package com.example.myfragmentexample;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class TextFragment extends Fragment {
    private static TextView textview;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.text_fragment, container, false);

        textview = (TextView) view.findViewById(R.id.textView1);

        return view;
    }

    public void zmienWlasciwosci (int fontsize, String text){
        textview.setTextSize(fontsize);
        textview.setText(text);
    }

}

text_fragment.xml:

<?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/textView1"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_centerHorizontal="true"
       android:layout_centerVertical="true"
       android:text="@string/text_label"
       android:textAppearance="?android:attr/textAppearanceLarge" /> 

</RelativeLayout>

安卓 list :

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.myfragmentexample"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="19" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.myfragmentexample.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

我阅读了很多关于此错误的帖子，但我在我的代码中找不到任何错误。我扩展了 android.support.v4.app.FragmentActivity。

最佳答案

Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.fragmentexample.ToolbarFragment" on path: DexPathList[[zip file "/data/app/com.example.myfragmentexample-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.myfragmentexample-1, /system/lib]]

这个

android:name="com.example.fragmentexample.ToolbarFragment"

必须是

android:name="com.example.myfragmentexample.ToolbarFragment"

因为 ToolbarFragment.java 的包名是

package com.example.myfragmentexample;

与 TextFragment 类似

android:name="com.example.myfragmentexample.TextFragment"

关于java - 安卓.view.InflateException : Binary XML file line #10: Error inflating class fragment，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/23424040/