Android 在不同的类中，将两个arrayList合并为一个

嗨，我班上有两个ListArray。我想在activity类中使用一个类，但我想将它们放在一个arrayList中，该arrayList存在于我所有应用程序中定义的公共类中。数据名是数据 我的第一个类包含以下数组：

//Class1

public static ArrayList<String> array1=new ArrayList<String>();
public static ArrayList<String> array2=new ArrayList<String>();


//Data
public static ArrayList<Class1> getE = new ArrayList<Class1>();

第一个问题：如何将array1和array2中的值放入数据类getE中的数组

第二个问题：为什么当我在ActivityClass中使用obj时应用程序崩溃了

09-25 07:03:04.888: E/UNIVERSITY(645): Size of List Before 0
09-25 07:03:06.948: I/dalvikvm(645): threadid=3: reacting to signal 3
09-25 07:06:54.738: E/AndroidRuntime(645): FATAL EXCEPTION: main
09-25 07:06:54.738: E/AndroidRuntime(645): java.lang.NullPointerException
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.PersonalHome$1.onItemClick(PersonalHome.java:61)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.CarouselAdapter.performItemClick(CarouselAdapter.java:261)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.Carousel.onSingleTapUp(Carousel.java:964)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.GestureDetector.onTouchEvent(GestureDetector.java:568)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.Carousel.onTouchEvent(Carousel.java:310)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.View.dispatchTouchEvent(View.java:5541)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1951)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1712)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1912)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1371)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.app.Activity.dispatchTouchEvent(Activity.java:2364)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1860)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.View.dispatchPointerEvent(View.java:5721)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:2890)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2466)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.processInputEvents(ViewRootImpl.java:845)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2475)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.os.Handler.dispatchMessage(Handler.java:99)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.os.Looper.loop(Looper.java:137)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.app.ActivityThread.main(ActivityThread.java:4424)
09-25 07:06:54.738: E/AndroidRuntime(645):  at java.lang.reflect.Method.invokeNative(Native Method)
09-25 07:06:54.738: E/AndroidRuntime(645):  at java.lang.reflect.Method.invoke(Method.java:511)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
09-25 07:06:54.738: E/AndroidRuntime(645):  at dalvik.system.NativeStart.main(Native Method)
09-25 07:18:01.538: E/AndroidRuntime(715):  at java.lang.reflect.Method.invoke(Method.java:511)

---

getE.clear（）；getE.addAll（数组1）；getE.addAll（array2）

c1.array1.get（1）.equals（“1”）

并避免使用静态变量。@st0le:第一条注释中的代码无法使用->不同类型！梅拉尔·阿布：请发布堆栈跟踪并改进您的问题的拼写。@user714965，我不知道这是

类

，很好的回答：P@user714965我刚刚在问题中添加了logcat:）

09-25 07:03:04.888: E/UNIVERSITY(645): Size of List Before 0
09-25 07:03:06.948: I/dalvikvm(645): threadid=3: reacting to signal 3
09-25 07:06:54.738: E/AndroidRuntime(645): FATAL EXCEPTION: main
09-25 07:06:54.738: E/AndroidRuntime(645): java.lang.NullPointerException
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.PersonalHome$1.onItemClick(PersonalHome.java:61)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.CarouselAdapter.performItemClick(CarouselAdapter.java:261)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.Carousel.onSingleTapUp(Carousel.java:964)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.GestureDetector.onTouchEvent(GestureDetector.java:568)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.university.app.controls.Carousel.onTouchEvent(Carousel.java:310)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.View.dispatchTouchEvent(View.java:5541)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1951)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1712)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:1957)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1726)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1912)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1371)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.app.Activity.dispatchTouchEvent(Activity.java:2364)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1860)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.View.dispatchPointerEvent(View.java:5721)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:2890)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2466)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.processInputEvents(ViewRootImpl.java:845)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2475)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.os.Handler.dispatchMessage(Handler.java:99)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.os.Looper.loop(Looper.java:137)
09-25 07:06:54.738: E/AndroidRuntime(645):  at android.app.ActivityThread.main(ActivityThread.java:4424)
09-25 07:06:54.738: E/AndroidRuntime(645):  at java.lang.reflect.Method.invokeNative(Native Method)
09-25 07:06:54.738: E/AndroidRuntime(645):  at java.lang.reflect.Method.invoke(Method.java:511)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
09-25 07:06:54.738: E/AndroidRuntime(645):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
09-25 07:06:54.738: E/AndroidRuntime(645):  at dalvik.system.NativeStart.main(Native Method)
09-25 07:18:01.538: E/AndroidRuntime(715):  at java.lang.reflect.Method.invoke(Method.java:511)