在 Android 2.2 上运行时，膨胀类 android.support.v4.app.fragment 时出错

Question

我想向 Android Foryo 添加对我的应用程序的支持。

但我似乎无法解决问题。我使用 Google 和 StackOverflow 进行了许多研究。我唯一得到的是我必须使用支持库使用<android.support.v4.app.fragment 而不是<fragment，但这也行不通！

每当我尝试运行应用程序时，它都会崩溃，并且在 LogCat 中出现此错误。

android.view.InflateException: Binary XML file line #40: Error inflating class android.support.v4.app.fragment

XML

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <TabHost
        android:id="@android:id/tabhost"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <LinearLayout
            android:id="@+id/LinearLayout01"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical" >

            <TabWidget
                android:id="@android:id/tabs"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" >
            </TabWidget>

            <FrameLayout
                android:id="@android:id/tabcontent"
                android:layout_width="match_parent"
                android:layout_height="match_parent" >
            </FrameLayout>
        </LinearLayout>
    </TabHost>

    <LinearLayout
        android:id="@+id/settings_fragment_layout"
        android:layout_width="280dp"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:background="#FFffffff"
        android:orientation="vertical" >

        <android.support.v4.app.fragment
            android:id="@+id/settings_fragment_section"
            android:name="com.example.SettingsFragment"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
    </LinearLayout>

</android.support.v4.widget.DrawerLayout>

Java

/**
 * 
 */
package com.example;

import android.app.TabActivity;
import android.os.Bundle;

/**
 * @author 
 * 
 */

public class MainActivity extends TabActivity {

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

SettingsFragment.java 只是……

package com.example;

import android.os.Bundle;

import com.nozzha.support.v4.preference.PreferenceFragment;

public class SettingsFragment extends PreferenceFragment {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preference_settings);
    }

}

LogCat

11-22 11:19:54.141: E/AndroidRuntime(1197): FATAL EXCEPTION: main
11-22 11:19:54.141: E/AndroidRuntime(1197): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example/com.example.MainActivity}: android.view.InflateException: Binary XML file line #40: Error inflating class android.support.v4.app.fragment
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.os.Looper.loop(Looper.java:123)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread.main(ActivityThread.java:4627)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at java.lang.reflect.Method.invokeNative(Native Method)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at java.lang.reflect.Method.invoke(Method.java:521)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at dalvik.system.NativeStart.main(Native Method)
11-22 11:19:54.141: E/AndroidRuntime(1197): Caused by: android.view.InflateException: Binary XML file line #40: Error inflating class android.support.v4.app.fragment
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.createView(LayoutInflater.java:503)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:565)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:618)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:621)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.inflate(LayoutInflater.java:407)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:198)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.Activity.setContentView(Activity.java:1647)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at com.example.MainActivity.onCreate(MainActivity.java:19)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
11-22 11:19:54.141: E/AndroidRuntime(1197):     ... 11 more
11-22 11:19:54.141: E/AndroidRuntime(1197): Caused by: java.lang.NoSuchMethodException: fragment(Context,AttributeSet)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at java.lang.Class.getMatchingConstructor(Class.java:660)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at java.lang.Class.getConstructor(Class.java:477)
11-22 11:19:54.141: E/AndroidRuntime(1197):     at android.view.LayoutInflater.createView(LayoutInflater.java:475)
11-22 11:19:54.141: E/AndroidRuntime(1197):     ... 22 more

Answer 1

那是因为您的 Activity 没有扩展基本 Activity FragmentActivity。如果您使用基于支持的片段，那么您的 Activity 必须扩展 FragmentActivity。

http://developer.android.com/reference/android/support/v4/app/FragmentActivity.html

Answer 2

请尝试添加构造函数。公共无效设置片段（）{}。 Activity 需要它来正确初始化 Fragment。