大神幫我看看這個錯在哪里了，小白求解決-有解無憂

05-28 11:56:24.640 3201-3201/? E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.weather, PID: 3201
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.weather/com.example.weather.MainActivity}: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.Object java.util.List.get(int)' on a null object reference
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
        at android.app.ActivityThread.-wrap11(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:148)
        at android.app.ActivityThread.main(ActivityThread.java:5417)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
     Caused by: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.Object java.util.List.get(int)' on a null object reference
        at com.example.weather.MainActivity.getMap(MainActivity.java:58)
        at com.example.weather.MainActivity.onCreate(MainActivity.java:54)
        at android.app.Activity.performCreate(Activity.java:6237)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
        at android.app.ActivityThread.-wrap11(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:148)
        at android.app.ActivityThread.main(ActivityThread.java:5417)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

uj5u.com熱心網友回復：

java.lang.Object java.util.List.get(int)' on a null object reference

java.lang.NullPointerException 空指標例外檢查下你的List物件有沒有初始化

uj5u.com熱心網友回復：

new ArryList<>();就好了，你沒new就想用這個集合List就會報這個錯誤

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標籤：Android

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