Question

我在Android工作室很新，所以我确信我只是错过了一些简单的东西。奇怪的是，这个应用程序有3个活动，前2个我可以切换没有问题，但第三个崩溃了。我已尽可能缩小代码范围，但我甚至无法换成完全空白的xml页面。

交换按钮代码：

public void goA3(View V) {
    Intent intent = new Intent(this, ThirdActivity.class);
    startActivity(intent);
}

ThirdActivity.class代码：

import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

public class ThirdActivity extends AppCompatActivity {

//  static final public String PREF_STRING_3 = "string_3";


AppInfo appInfo;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_third);
    appInfo = AppInfo.getInstance(this);
}
}

空白页的基本XML：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">

</LinearLayout>

再次感谢，我确信它缺少基本的东西。

logcat的：

FATAL EXCEPTION: main
                                                                                    Process: com.dealfaro.luca.backandforthstudio, PID: 2586
                                                                                    java.lang.IllegalStateException: Could not execute method for android:onClick
                                                                                        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:275)
                                                                                        at android.view.View.performClick(View.java:5637)
                                                                                        at android.view.View$PerformClick.run(View.java:22429)
                                                                                        at android.os.Handler.handleCallback(Handler.java:751)
                                                                                        at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                                        at android.os.Looper.loop(Looper.java:154)
                                                                                        at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                                                        at java.lang.reflect.Method.invoke(Native Method)
                                                                                        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
                                                                                     Caused by: java.lang.reflect.InvocationTargetException
                                                                                        at java.lang.reflect.Method.invoke(Native Method)
                                                                                        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:270)
                                                                                        at android.view.View.performClick(View.java:5637) 
                                                                                        at android.view.View$PerformClick.run(View.java:22429) 
                                                                                        at android.os.Handler.handleCallback(Handler.java:751) 
                                                                                        at android.os.Handler.dispatchMessage(Handler.java:95) 
                                                                                        at android.os.Looper.loop(Looper.java:154) 
                                                                                        at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                                        at java.lang.reflect.Method.invoke(Native Method) 
                                                                                        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
                                                                                     Caused by: android.content.ActivityNotFoundException: Unable to find explicit activity class {com.dealfaro.luca.backandforthstudio/com.dealfaro.luca.backandforthstudio.ThirdActivity}; have you declared this activity in your AndroidManifest.xml?
                                                                                        at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1805)
                                                                                        at android.app.Instrumentation.execStartActivity(Instrumentation.java:1523)
                                                                                        at android.app.Activity.startActivityForResult(Activity.java:4225)
                                                                                        at android.app.Activity.startActivityForResult(Activity.java:4183)
                                                                                        at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:784)
                                                                                        at android.app.Activity.startActivity(Activity.java:4522)
                                                                                        at android.app.Activity.startActivity(Activity.java:4490)
                                                                                        at com.dealfaro.luca.backandforthstudio.MainActivity.goA3(MainActivity.java:67)
                                                                                        at java.lang.reflect.Method.invoke(Native Method) 
                                                                                        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:270) 
                                                                                        at android.view.View.performClick(View.java:5637) 
                                                                                        at android.view.View$PerformClick.run(View.java:22429) 
                                                                                        at android.os.Handler.handleCallback(Handler.java:751) 
                                                                                        at android.os.Handler.dispatchMessage(Handler.java:95) 
                                                                                        at android.os.Looper.loop(Looper.java:154) 
                                                                                        at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                                        at java.lang.reflect.Method.invoke(Native Method) 
                                                                                        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

Answer 1

您需要将第三个活动添加到清单中。

<activity android:name="com.yourpackage.ThirdActivity"/>

Answer 2

在Android Manifest文件中添加您的活动，它肯定会有效

Android在切换到新活动时崩溃

2 个答案: