小菜鸟级:Unfortunately,ActivityTest has stopped解决办法!!!

目的是如图片:目标图片
FirtsActivity. java文件:
package com.example.activitytest;
import android.os.Bundle;
import android.app.Activity;
public class FirstActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.first_layout);
}

}
first_layout文件:
<?xml version="1.0" encoding="utf-8"?>
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="@+id/button_1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button 1"

/>
AndroidMainfest.xml:
     <manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.activitytest"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="L"
    android:targetSdkVersion="21" />

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.activitytest.FirstActivit"
        android:label="This is FirstActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>


Logcat:图片说明

AndroidManifest里面FirstActivity的定义你写错了
你写成了android:name="com.example.activitytest.FirstActivit"
应该是android:name="com.example.activitytest.FirstActivity"

我也遇到了,怎么解决啊