删除arrayList,java.lang.UnsupportedOperationException中的项

Sel*_*pan 4 android arraylist

我想在数组列表选择位置删除项目

我的代码是

    List<String> historylist = Arrays.asList(history);
    if (historylist.size()>=3){
        System.out.print("*************************************************");
        Log.i(MyContants.StoredHistory_TAG,"StoredHistory size========="+ String.valueOf(historylist.size()));
        String removePosition=historylist.get(2);
        historylist.remove(removePosition);
    }
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但是我得到了一个Exception UnsupportedOperationException

错误

    12-20 09:16:27.680: I/StoredHistory Class(5715): StoredHistory size=========3
    12-20 09:16:27.680: D/AndroidRuntime(5715): Shutting down VM
    12-20 09:16:27.684: W/dalvikvm(5715): threadid=1: thread exiting with uncaught exception (group=0x4001d7d0)
    12-20 09:16:27.688: E/AndroidRuntime(5715): FATAL EXCEPTION: main
    12-20 09:16:27.688: E/AndroidRuntime(5715): java.lang.RuntimeException: Unable to start activity ComponentInfo{****PACKAGE NAME*****}: java.lang.UnsupportedOperationException
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.os.Handler.dispatchMessage(Handler.java:99)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.os.Looper.loop(Looper.java:123)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.main(ActivityThread.java:4627)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at java.lang.reflect.Method.invokeNative(Native Method)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at java.lang.reflect.Method.invoke(Method.java:521)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at dalvik.system.NativeStart.main(Native Method)
    12-20 09:16:27.688: E/AndroidRuntime(5715): Caused by: java.lang.UnsupportedOperationException
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at java.util.AbstractList.remove(AbstractList.java:645)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at java.util.AbstractList$SimpleListIterator.remove(AbstractList.java:77)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at java.util.AbstractCollection.remove(AbstractCollection.java:230)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at ******.utills.StoredHistory.storedHistorylist(StoredHistory.java:24)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at *******.ScanResult.onCreate(ScanResult.java:53)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     ... 11 more
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如何解决这个问题..推进thanx老兄

ρяσ*_*я K 6

更改

List<String> historylist = Arrays.asList(history);
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 List<String> historylist = new LinkedList (Arrays.asList(history));
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并看到这篇文章为什么在List的情况下发生此错误:

尝试从List中删除元素时,为什么会出现UnsupportedOperationException?


Ted*_*opp 5

您无法在返回的列表中添加或删除元素,Arrays.asList因为列表由原始数组支持.要创建可以修改的列表,可以执行以下操作:

List<String> historylist = new ArrayList<String>(Arrays.asList(history));
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