我正在使用 resolveActivityInfo 来确定我的应用程序是否被设置为家庭启动器:
PackageManager pm = getPackageManager();
Intent intent = new Intent(Intent.ACTION_MAIN, null);
intent.addCategory(Intent.CATEGORY_HOME);
userHomePackage = intent.resolveActivityInfo(pm, 0).packageName;
userHomeActivityClass = intent.resolveActivityInfo(pm, 0).name;
currentHomeLauncherName = intent.resolveActivityInfo(pm, 0).loadLabel(pm).toString();
它在模拟器和我手头上的三个安卓设备上运行良好。
最近我开始收到来自用户的错误报告,错误日志显示 resolveActivityInfo 失败。正如我所见,这仅发生在运行 android 2.1 update 1 的少数手机上。由于这个问题,我已经收到很多关于我的应用程序的正面评论和一些负面评论。
任何建议可能是错的?
java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1224)
at android.os.Parcel.readException(Parcel.java:1206)
at android.content.pm.IPackageManager$Stub$Proxy.resolveIntent(IPackageManager.java:1418)
at android.app.ApplicationContext$ApplicationPackageManager.resolveActivity(ApplicationContext.java:2046)
at android.content.Intent.resolveActivityInfo(Intent.java:3790)
at com.myapp.myappname.Launcher.setAsHomeApplicationBeforeFroyo(Launcher.java:336)
或
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myapp.myappname/com.myapp.myappname.Launcher}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2497)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2513)
at android.app.ActivityThread.access$2200(ActivityThread.java:119)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1864)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4370)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:862)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1224)
at android.os.Parcel.readException(Parcel.java:1206)
at android.content.pm.IPackageManager$Stub$Proxy.resolveIntent(IPackageManager.java:1418)
at android.app.ApplicationContext$ApplicationPackageManager.resolveActivity(ApplicationContext.java:2046)
at android.content.Intent.resolveActivityInfo(Intent.java:3790)
at com.myapp.myappname.Launcher.showHomeChooserDialog(Launcher.java:141)
at com.myapp.myappname.Launcher.showNextActivity(Launcher.java:122)
at com.myapp.myappname.Launcher.onCreate(Launcher.java:59)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2460)
... 11 more
java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1224)
at android.os.Parcel.readException(Parcel.java:1206)
at android.content.pm.IPackageManager$Stub$Proxy.resolveIntent(IPackageManager.java:1418)
at android.app.ApplicationContext$ApplicationPackageManager.resolveActivity(ApplicationContext.java:2046)
at android.content.Intent.resolveActivityInfo(Intent.java:3790)
at com.myapp.myappname.Launcher.showHomeChooserDialog(Launcher.java:141)
最佳答案
来自 TeslaCoil Software 的 Kevin。很抱歉延迟回复您。这就是我用来在我的应用程序中获取 Home 组件的方法:
public static ComponentName getHomeComponent(PackageManager PM) {
Intent home_intent = new Intent("android.intent.action.MAIN");
home_intent.addCategory("android.intent.category.HOME");
home_intent.addCategory("android.intent.category.DEFAULT");
ComponentName cn = home_intent.resolveActivity(PM);
if (cn == null)
Log.v(TAG, "[Default] package:null");
else
Log.v(TAG, "[Default] package:" + cn.getPackageName() + " class:" + cn.getClassName());
return cn;
}
resolveActivity 通常不会返回 null,因为如果没有默认设置,它似乎会返回解析器 Activity 。但在某些手机或其他东西上,它可能会返回 null 只是为了让事情变得有趣。也许 resolveActivityInfo 调用 resolveActivity 但没有正确处理 null 情况。
关于android - 解决 Intent Activity 的问题 - resolveActivityInfo(),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/4867106/