Android片段：在片段之间切换，发生InflateException

时间：2014-09-23 08:11:14

标签： java android android-fragments

我是片段新手，想要在主要活动中有下一个和上一个按钮的情况下实现它，然后点击下一个按钮它会转到下一个片段，按下前一个按钮就会转到因为我想将第一个片段设置为起始片段。所以我做了以下事情：

package com.example.marinasignup;

import android.os.Bundle;
import android.app.Activity;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends FragmentActivity {
RegistrationData robj;
Button btnnext,btnprev;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btnnext=(Button) findViewById(R.id.btnnext);
        btnprev=(Button) findViewById(R.id.btnprev);
        robj=new RegistrationData();
        FragmentManager fragmentManager = getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                FragmentOne fragment = new FragmentOne();
                fragmentTransaction.add(R.id.signup_fragment, fragment);
                fragmentTransaction.commit();
        btnnext.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {


            }
        });
        btnprev.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {


            }
        });
    }



}

但我在logcat中遇到以下错误：

09-23 13:35:00.671: E/AndroidRuntime(20940): FATAL EXCEPTION: main
09-23 13:35:00.671: E/AndroidRuntime(20940): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.marinasignup/com.example.marinasignup.MainActivity}: android.view.InflateException: Binary XML file line #11: Error inflating class fragment
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.os.Handler.dispatchMessage(Handler.java:99)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.os.Looper.loop(Looper.java:130)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread.main(ActivityThread.java:3689)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.reflect.Method.invokeNative(Native Method)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.reflect.Method.invoke(Method.java:507)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at dalvik.system.NativeStart.main(Native Method)
09-23 13:35:00.671: E/AndroidRuntime(20940): Caused by: android.view.InflateException: Binary XML file line #11: Error inflating class fragment
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:587)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:209)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.Activity.setContentView(Activity.java:1657)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at com.example.marinasignup.MainActivity.onCreate(MainActivity.java:20)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
09-23 13:35:00.671: E/AndroidRuntime(20940):    ... 11 more
09-23 13:35:00.671: E/AndroidRuntime(20940): Caused by: java.lang.NullPointerException
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.VMClassLoader.findLoadedClass(Native Method)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:389)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.ClassLoader.loadClass(ClassLoader.java:541)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.support.v4.app.Fragment.isSupportFragmentClass(Fragment.java:436)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:255)
09-23 13:35:00.671: E/AndroidRuntime(20940):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:563)
09-23 13:35:00.671: E/AndroidRuntime(20940):    ... 20 more

main的xml文件如下所示：

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <fragment
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/signup_fragment"
        />

    <Button
        android:id="@+id/btnprev"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_marginRight="31dp"
        android:layout_toLeftOf="@+id/btnnext"
        android:text="PREV" />

    <Button
        android:id="@+id/btnnext"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/btnprev"
        android:layout_alignBottom="@+id/btnprev"
        android:layout_alignRight="@+id/signup_fragment"
        android:layout_marginRight="73dp"
        android:text="NEXT" />

</RelativeLayout>

fragmentone代码：

package com.example.marinasignup;

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

public class FragmentOne extends Fragment {

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

}

fragmentone.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"
    android:background="#4ECDC4"
    android:id="@+id/frag1"
    >

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"
    android:text="FRAGMENT ONE" />

</RelativeLayout>

1 个答案:

答案 0 :(得分：1)

请相信我，不要尝试自己实现该功能。我做了（为了一个特殊的用例来很好地支持手机和平板电脑的屏幕），它并不好玩。改为使用ViewPager和FragmentPagerAdapter。

相关问题
最新问题