我是android工作环境的新手，正在学习一些关于片段的教程，当我构建和运行项目时似乎没有错误，但是一旦在模拟器上安装了应用程序，我就会在对话框中收到这条消息，说应用程序已停止在职的
我花了一整天的时间寻找解决方案，现在任何帮助将不胜感激，下面是源代码：MainActivity.java：
package com.example.fragmentsanotherexample;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.Menu;
public class MainActivity extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fm=getSupportFragmentManager();
android.support.v4.app.Fragment fragment=fm.findFragmentById(R.id.fragment_content);
if(fragment==null){
FragmentTransaction ft=fm.beginTransaction();
ft.add(R.id.fragment_content, new BasicFragment());
ft.commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
基本片段.java：
package com.example.fragmentsanotherexample;
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.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class BasicFragment extends Fragment{
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View view=inflater.inflate(R.layout.basic_fragment,container,false);
Button button=(Button) view.findViewById(R.id.fragment_button);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Activity activity=getActivity();
if(activity != null){
Toast.makeText(activity, R.string.hello_world, Toast.LENGTH_LONG).show();
}
}
});
return view;
}
}
这是 basic_fragment.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button android:id="@+id/fragment_button"
android:text="@string/btn_fragment"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
这是activiy_main.xml：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<FragmentLayout
android:id="@+id/fragment_content"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
这是清单文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.fragmentsanotherexample"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.fragmentsanotherexample.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>
就 logcat 而言，它是空的，任何形式的帮助都将不胜感激