第三方jar中的Activity,调用时出错。

[wolun2010]

错误日志如下
04-19 11:28:17.853: E/AndroidRuntime(12084): FATAL EXCEPTION: main
04-19 11:28:17.853: E/AndroidRuntime(12084): Process: com.cxyliuyu.cyjszs, PID: 12084
04-19 11:28:17.853: E/AndroidRuntime(12084): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cxyliuyu.cyjszs/com.zxt.download2.DownloadListActivity}: java.lang.NullPointerException
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2212)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2271)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread.access$800(ActivityThread.java:144)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.os.Handler.dispatchMessage(Handler.java:102)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.os.Looper.loop(Looper.java:136)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread.main(ActivityThread.java:5146)
04-19 11:28:17.853: E/AndroidRuntime(12084): at java.lang.reflect.Method.invokeNative(Native Method)
04-19 11:28:17.853: E/AndroidRuntime(12084): at java.lang.reflect.Method.invoke(Method.java:515)
04-19 11:28:17.853: E/AndroidRuntime(12084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:732)
04-19 11:28:17.853: E/AndroidRuntime(12084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:566)
04-19 11:28:17.853: E/AndroidRuntime(12084): at dalvik.system.NativeStart.main(Native Method)
04-19 11:28:17.853: E/AndroidRuntime(12084): Caused by: java.lang.NullPointerException
04-19 11:28:17.853: E/AndroidRuntime(12084): at com.zxt.download2.Res.<init>(Unknown Source)
04-19 11:28:17.853: E/AndroidRuntime(12084): at com.zxt.download2.Res.getInstance(Unknown Source)
04-19 11:28:17.853: E/AndroidRuntime(12084): at com.zxt.download2.DownloadListActivity.onCreate(Unknown Source)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.Activity.performCreate(Activity.java:5341)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
04-19 11:28:17.853: E/AndroidRuntime(12084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2169)
04-19 11:28:17.853: E/AndroidRuntime(12084): ... 11 more

[雪月弦歌]

没这样搞过，不过可以想像下像支付宝微信这种第三方SDK注册activity时的方法，借鉴下。比如用自己的activity去继承它的，然后注册？

[wolun2010]

第三方的jar包中activity的包名跟我自己程序的包名完全不一样。这种情况下应该怎么在manifest中注册这个activity 呢

[yexianghu]

首先，jar包中得activity和自己写得activity注册方法一样，唯一要注意的是，jar包中得activity在注册的时候需要填写完成的类名，例如：要 写成 com.zxt.download2.DownloadListActivity 而不能只写 DownloadListActivity 然后，从log上看，你的问题似乎不是activity没注册引起的，应该是 com.zxt.download2.Res 这个类在new的时候，构造函数中出现了空指针异常导致的。