Java 无法将注册按钮重定向到注册页,因为发生无法启动活动组件信息错误
我正在尝试实现一个登录活动。在登录活动中,我必须输入手机号码和密码,然后单击登录按钮 这是我的Java 无法将注册按钮重定向到注册页,因为发生无法启动活动组件信息错误,java,android,Java,Android,我正在尝试实现一个登录活动。在登录活动中,我必须输入手机号码和密码,然后单击登录按钮 这是我的活动\u login.xml <ScrollView xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/scrollView1" android:layout_width="mat
活动\u login.xml
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/background2"
tools:context="com.myayubo.LoginActivity"
android:fillViewport="false">
<RelativeLayout
android:id="@+id/RelativeLayout"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<RelativeLayout
android:id="@+id/RelativeLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="25dp">
<LinearLayout
android:id="@+id/LinearLayouttxtayubo"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<TextView
android:id="@+id/textAyubo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Ayubo"
android:layout_gravity="center"
android:typeface="normal"
android:textStyle="bold"
android:textColor="#FFFFFF"
android:textSize="35dp" />
</LinearLayout>
<LinearLayout
android:id="@+id/LinearLayouttxtexplorer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/LinearLayouttxtayubo"
android:orientation="vertical">
<TextView
android:id="@+id/textExplore"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Explore places nearby you"
android:layout_centerHorizontal="true"
android:typeface="serif"
android:layout_gravity="center"
android:textColor="#FFFFFF"
android:textSize="12dp"/>
</LinearLayout>
</RelativeLayout>
<LinearLayout
android:id="@+id/LinearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="1"
android:layout_marginTop="224dp"
android:layout_below="@+id/RelativeLayout1"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
<EditText
android:id="@+id/mobileNo"
android:layout_width="250dp"
android:layout_height="30dp"
android:hint="Mobile Number"
android:textColorHint="#FFFFFF"
android:gravity="center"
android:inputType="phone"
android:layout_gravity="center"
android:background="@drawable/shape"
android:layout_marginTop="10dp"
android:textSize="15dp"
>
<requestFocus />
</EditText>
<EditText
android:id="@+id/password"
android:layout_width="250dp"
android:layout_height="30dp"
android:hint="Password"
android:textColorHint="#FFFFFF"
android:inputType="textPassword"
android:layout_gravity="center"
android:background="@drawable/shape"
android:layout_marginTop="10dp"
android:gravity="center"
android:textSize="15dp"/>
<Button
android:id="@+id/loginBtn"
android:text="Login"
android:layout_width="260dp"
android:layout_height="38dp"
android:layout_gravity="center"
android:layout_marginTop="10dp"
android:alpha="0.5" />
<Button
android:id="@+id/fbbtn"
android:text="Connect with Facebook"
android:layout_width="250dp"
android:layout_height="26dp"
android:layout_gravity="center"
android:layout_marginTop="10dp"
android:background="#ADD8E6"
android:alpha="0.5"
/>
<TextView
android:id="@+id/text2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/fbbtn"
android:layout_marginTop="20dp"
android:text="or Sign Up"
android:layout_gravity="center"/>
</LinearLayout>
</RelativeLayout>
</ScrollView>
看起来这里有点不对劲。因为,当我试图运行此代码时,我的应用程序崩溃。它显示以下错误
java.lang.RuntimeException:无法启动活动组件信息{com.myayubo/com.myayubo.LoginActivity}:java.lang.NullPointerException
但是,没有注册按钮的意图,它可以工作
这是我的日志
11-05 10:36:58.359 27532-27532/com.myayubo E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.myayubo, PID: 27532
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myayubo/com.myayubo.LoginActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2338)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5299)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.myayubo.LoginActivity.onCreate(LoginActivity.java:57)
at android.app.Activity.performCreate(Activity.java:5264)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1088)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2302)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5299)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645)
at dalvik.system.NativeStart.main(Native Method)
请告诉我如何处理这个错误
提前到达塔克斯
-编辑-
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.myayubo"
android:versionCode="1"
android:versionName="1.0" >
<supports-screens
android:anyDensity="true"
android:largeScreens="true"
android:normalScreens="true"
android:resizeable="true"
android:smallScreens="true"
android:xlargeScreens="true" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<!--
The ACCESS_COARSE/FINE_LOCATION permissions are not required to use
Google Maps Android API v2, but are recommended.
-->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<!--
To retrieve OAuth 2.0 tokens or invalidate tokens to disconnect a user. This disconnect
option is required to comply with the Google+ Sign-In developer policies
-->
<uses-permission android:name="android.permission.USE_CREDENTIALS" /> <!-- To retrieve the account name (email) as part of sign-in: -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" /> <!-- To auto-complete the email text field in the login form with the user's emails -->
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="@string/google_maps_key" />
<activity
android:name=".MapsActivity"
android:label="@string/title_activity_maps" >
</activity>
<activity
android:name=".LoginActivity"
android:label="@string/title_activity_login"
android:windowSoftInputMode="adjustResize|stateHidden" >
</activity>
<activity
android:name=".Splash"
android:label="Ayubo" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ExtractMenu"
android:label="@string/title_activity_extract_menu" >
</activity>
<activity
android:name=".sign_up"
android:label="@string/title_activity_sign_up" >
</activity>
</application>
</manifest>
NullPointerException
,因为在activity\u login.xml
布局中没有id为signUp
的TextView
在onCreate方法中
signUp = (TextView) findViewById(R.id.signUp);
但是由于您的activity\u login.xml
不包含TextView
和id
注册
它返回空值
然后再次尝试在TextView
上设置侦听器,它是空的,因此NullPointerException
signUp.setOnClickListener(this);
看来你不该在这里设置身份证
<TextView
android:id="@+id/text2" //android:id="@+id/signUp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/fbbtn"
android:layout_marginTop="20dp"
android:text="or Sign Up"
android:layout_gravity="center"/>
NullPointerException
,因为在activity\u login.xml
布局中没有id为signUp
的TextView
在onCreate方法中
signUp = (TextView) findViewById(R.id.signUp);
但是由于您的activity\u login.xml
不包含TextView
和id
注册
它返回空值
然后再次尝试在TextView
上设置侦听器,它是空的,因此NullPointerException
signUp.setOnClickListener(this);
看来你不该在这里设置身份证
<TextView
android:id="@+id/text2" //android:id="@+id/signUp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/fbbtn"
android:layout_marginTop="20dp"
android:text="or Sign Up"
android:layout_gravity="center"/>
您正在获得NPE,因为您正在尝试添加xml文件中没有的视图
signUp = (TextView) findViewById(R.id.signUp);
您的xml中没有具有此id的文本视图。请检查它。如果您删除此id,则您的代码将运行正常您正在获得NPE,因为您正在尝试添加不在xml文件中的视图
signUp = (TextView) findViewById(R.id.signUp);
您的xml中没有此id的文本视图。请检查它。如果删除此id,您的代码将运行正常将清单文件添加活动发布到AndroidManifest.xml文件将清单文件添加活动发布到AndroidManifest.xml文件哦!我真傻。谢谢你,哦!我真傻。谢谢你。