android - NullPointerException 获取 StringArray 到 String[]

Question

好的，我的 strings.xml 文件中有 5 个数组，每个数组都包含 5 个元素，如下所示:

<string-array name="monday">
        <item>monday</item>
        <item>tuesday</item>
        <item>wednesday</item>
        <item>thursday</item>
        <item>friday</item>
    </string-array>

现在我的代码中有一个 switch 语句，它依赖于他们单击的按钮将这 5 个数组之一设置为我的主数组。但是我尝试了很多不同的方法，但我仍然在这一行得到空指针异常:

Days.masterarray = getResources().getStringArray(R.array.monday);

也证实了这一点，但得到了相同的结果:

Days.setMasterarray(getResources().getStringArray(R.array.monday));

主数组:

public static String[] masterarray = new String[] { "monday", "tuesday",
            "wednesday", "thursday", "friday" };

我一开始就给了它默认值。现在，当我运行 switch 语句时，我得到了这个:

03-19 13:43:23.555: WARN/System.err(1379): java.lang.NullPointerException
03-19 13:43:23.586: WARN/System.err(1379):     at android.content.ContextWrapper.getResources(ContextWrapper.java:81)
03-19 13:43:23.586: WARN/System.err(1379):     at schoolBook.Icestone.Days.setArray(Days.java:77)
03-19 13:43:23.595: WARN/System.err(1379):     at schoolBook.Icestone.SampleActivity.onCreate(SampleActivity.java:27)
03-19 13:43:23.605: WARN/System.err(1379):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1048)
03-19 13:43:23.626: WARN/System.err(1379):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1700)
03-19 13:43:23.626: WARN/System.err(1379):     at android.app.ActivityThread.startActivityNow(ActivityThread.java:1577)
03-19 13:43:23.635: WARN/System.err(1379):     at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:130)
03-19 13:43:23.644: WARN/System.err(1379):     at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:342)
03-19 13:43:23.655: WARN/System.err(1379):     at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:680)
03-19 13:43:23.676: WARN/System.err(1379):     at android.widget.TabHost.setCurrentTab(TabHost.java:349)
03-19 13:43:23.676: WARN/System.err(1379):     at android.widget.TabHost.addTab(TabHost.java:239)
03-19 13:43:23.695: WARN/System.err(1379):     at schoolBook.Icestone.Days.onCreate(Days.java:32)
03-19 13:43:23.695: WARN/System.err(1379):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1048)
03-19 13:43:23.695: WARN/System.err(1379):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1700)
03-19 13:43:23.716: WARN/System.err(1379):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1752)
03-19 13:43:23.716: WARN/System.err(1379):     at android.app.ActivityThread.access$1500(ActivityThread.java:123)
03-19 13:43:23.716: WARN/System.err(1379):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:993)
03-19 13:43:23.735: WARN/System.err(1379):     at android.os.Handler.dispatchMessage(Handler.java:99)
03-19 13:43:23.735: WARN/System.err(1379):     at android.os.Looper.loop(Looper.java:126)
03-19 13:43:23.744: WARN/System.err(1379):     at android.app.ActivityThread.main(ActivityThread.java:3997)
03-19 13:43:23.754: WARN/System.err(1379):     at java.lang.reflect.Method.invokeNative(Native Method)
03-19 13:43:23.754: WARN/System.err(1379):     at java.lang.reflect.Method.invoke(Method.java:491)
03-19 13:43:23.754: WARN/System.err(1379):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
03-19 13:43:23.775: WARN/System.err(1379):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
03-19 13:43:23.775: WARN/System.err(1379):     at dalvik.system.NativeStart.main(Native Method)

任何有关如何解决此问题的信息都将不胜感激

Answer 1

我认为 getResources 可能为空。试试看

• 在该行打断点，调试看是否为null(如果不为null，再找什么为null)
• 使用上下文。即。
  mContext.getResources().getStringArray(R.array.monday));