难以将单独的项目集成到其他项目中

Question

我有一个包含三个按钮的 gui 项目。现在其中一个按钮将与其他活动相关联。我已经单独开发了此活动的代码并对其进行了测试，但现在当我将其集成到我的主 gui 项目显示错误。（单击按钮将获取谷歌地图上的当前位置）。

这是我的日志猫：

10-27 01:45:44.533: E/ActivityThread(357): Failed to find provider info for com.google.settings
10-27 01:45:44.563: E/ActivityThread(357): Failed to find provider info for com.google.settings
10-27 01:45:44.633: D/AndroidRuntime(357): Shutting down VM
10-27 01:45:44.633: W/dalvikvm(357): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
10-27 01:45:44.643: E/AndroidRuntime(357): Uncaught handler: thread main exiting due to uncaught exception
10-27 01:45:44.653: E/AndroidRuntime(357): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.gui/com.example.gui.LocationActivity}: java.lang.NullPointerException
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread.access$2200(ActivityThread.java:119)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.os.Handler.dispatchMessage(Handler.java:99)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.os.Looper.loop(Looper.java:123)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread.main(ActivityThread.java:4363)
10-27 01:45:44.653: E/AndroidRuntime(357):  at java.lang.reflect.Method.invokeNative(Native Method)
10-27 01:45:44.653: E/AndroidRuntime(357):  at java.lang.reflect.Method.invoke(Method.java:521)
10-27 01:45:44.653: E/AndroidRuntime(357):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
10-27 01:45:44.653: E/AndroidRuntime(357):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
10-27 01:45:44.653: E/AndroidRuntime(357):  at dalvik.system.NativeStart.main(Native Method)
10-27 01:45:44.653: E/AndroidRuntime(357): Caused by: java.lang.NullPointerException
10-27 01:45:44.653: E/AndroidRuntime(357):  at com.example.gui.LocationActivity.onCreate(LocationActivity.java:50)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-27 01:45:44.653: E/AndroidRuntime(357):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
10-27 01:45:44.653: E/AndroidRuntime(357):  ... 11 more
10-27 01:45:44.693: I/dalvikvm(357): threadid=7: reacting to signal 3
10-27 01:45:44.693: E/dalvikvm(357): Unable to open stack trace file '/data/anr/traces.txt': Permission denied

谁能帮我解决这个问题？

Answer 1

您收到错误消息是因为在第 50 行调用时

map.setBuiltInZoomControls(true);

您的 map 变量为空。请发布您的 main.xml 文件，因为这是您调用 findViewById 时您的 onCreate 方法正在寻找视图的位置，因为您调用了

setContentView(R.layout.main);