从Android 6.0版本开始，系统启用更加严格的权限管理，部分重要权限只能在运行过程由用户授权，无法通过声明获得。如READ_PHONE_STATE这种权限，即使在AndroidManifest中已经声明，如果既没有在运行时向用户请求，又没有做相应处理，就会导致应用闪退。
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java.lang.RuntimeException: Error receiving broadcast Intent { act=android.net.conn.CONNECTIVITY_CHANGE flg=0x4000010 (has extras) }
in com.quanshi.tang.network.NetworkUtils$ConnectReceiver@2a526a5
at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:1235)
at android.os.Handler.handleCallback(Handler.java:761)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6585)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)
Caused by: java.lang.SecurityException: getSubscriberId: Neither user 10190 nor current process has android.permission.READ_PHONE_STATE.
at android.os.Parcel.readException(Parcel.java:1665)
at android.os.Parcel.readException(Parcel.java:1618)
at com.android.internal.telephony.IPhoneSubInfo$Stub$Proxy.getSubscriberIdForSubscriber(IPhoneSubInfo.java:590)
at android.telephony.TelephonyManager.getSubscriberId(TelephonyManager.java:2208)
at android.telephony.TelephonyManager.getSubscriberId(TelephonyManager.java:2189)
at com.quanshi.tang.network.NetworkUtils.getProvidersName(Unknown Source)
at com.quanshi.tang.network.NetworkUtils.getNetworkInfo(Unknown Source)
at com.quanshi.tang.network.NetworkUtils.connectChanged(Unknown Source)
at com.quanshi.tang.network.NetworkUtils.access$100(Unknown Source)
at com.quanshi.tang.network.NetworkUtils$ConnectReceiver.onReceive(Unknown Source)
at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:1222)
at android.os.Handler.handleCallback(Handler.java:761)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6585)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)
但apk可通过build.gradle的targetSDK表明最高支持的系统版本。已知新的权限系统只在Android 6.0(23)及以上的系统有效，那把targetSDK设置小于等于22即可避开新的权限管理。