diff --git a/app/src/main/java/luyao/util/ktx/ui/IntentExtActivity.kt b/app/src/main/java/luyao/util/ktx/ui/IntentExtActivity.kt
index c080ad9..67246fc 100644
--- a/app/src/main/java/luyao/util/ktx/ui/IntentExtActivity.kt
+++ b/app/src/main/java/luyao/util/ktx/ui/IntentExtActivity.kt
@@ -1,6 +1,9 @@
 package luyao.util.ktx.ui
 
 import android.Manifest
+import android.content.Context
+import android.os.PowerManager
+import android.view.WindowManager
 import com.afollestad.materialdialogs.MaterialDialog
 import com.afollestad.materialdialogs.files.FileFilter
 import com.afollestad.materialdialogs.files.fileChooser
@@ -45,6 +48,7 @@ class IntentExtActivity : CommonListActivity() {
 
     private fun installApk() {
 
+powerManager
         request(Manifest.permission.READ_EXTERNAL_STORAGE) {
             onGranted {
                 chooseFile()
diff --git a/ktx/src/main/java/luyao/util/ktx/base/BaseVMActivity.kt b/ktx/src/main/java/luyao/util/ktx/base/BaseVMActivity.kt
index 9b72b7a..6627cb7 100644
--- a/ktx/src/main/java/luyao/util/ktx/base/BaseVMActivity.kt
+++ b/ktx/src/main/java/luyao/util/ktx/base/BaseVMActivity.kt
@@ -2,7 +2,9 @@ package luyao.util.ktx.base
 
 import android.os.Bundle
 import androidx.lifecycle.LifecycleObserver
+import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
+import java.lang.Exception
 
 /**
  * Created by luyao
@@ -28,7 +30,11 @@ abstract class BaseVMActivity<VM : BaseViewModel> : BaseActivity(),LifecycleObse
     open fun providerVMClass(): Class<VM>? = null
 
 
-    open fun startObserve() {}
+    open fun startObserve() {
+        mViewModel.mException.observe(this, Observer { it?.let { onError(it) } })
+    }
+
+    open fun onError(e: Exception){}
 
     override fun onDestroy() {
         mViewModel.let {
diff --git a/ktx/src/main/java/luyao/util/ktx/base/BaseVMFragment.kt b/ktx/src/main/java/luyao/util/ktx/base/BaseVMFragment.kt
index 24a8dc9..23c9273 100644
--- a/ktx/src/main/java/luyao/util/ktx/base/BaseVMFragment.kt
+++ b/ktx/src/main/java/luyao/util/ktx/base/BaseVMFragment.kt
@@ -4,7 +4,9 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
+import java.lang.Exception
 
 /**
  * Created by luyao
@@ -26,7 +28,12 @@ abstract class BaseVMFragment<VM : BaseViewModel> : androidx.fragment.app.Fragme
         super.onViewCreated(view, savedInstanceState)
     }
 
-    open fun startObserve() {}
+    open fun startObserve() {
+        mViewModel.mException.observe(this, Observer { it?.let { onError(it) } })
+    }
+
+    open fun onError(e:Exception){}
+
     abstract fun getLayoutResId(): Int
 
     abstract fun initView()
diff --git a/ktx/src/main/java/luyao/util/ktx/base/BaseViewModel.kt b/ktx/src/main/java/luyao/util/ktx/base/BaseViewModel.kt
index 908c959..8c45436 100644
--- a/ktx/src/main/java/luyao/util/ktx/base/BaseViewModel.kt
+++ b/ktx/src/main/java/luyao/util/ktx/base/BaseViewModel.kt
@@ -12,7 +12,7 @@ import kotlinx.coroutines.*
  */
 open class BaseViewModel : ViewModel(), LifecycleObserver {
 
-    private val mException: MutableLiveData<Exception> = MutableLiveData()
+    val mException: MutableLiveData<Exception> = MutableLiveData()
 
 
     private fun launchOnUI(block: suspend CoroutineScope.() -> Unit) {
diff --git a/ktx/src/main/java/luyao/util/ktx/ext/SystemServiceExt.kt b/ktx/src/main/java/luyao/util/ktx/ext/SystemServiceExt.kt
index 72f6d24..015947d 100644
--- a/ktx/src/main/java/luyao/util/ktx/ext/SystemServiceExt.kt
+++ b/ktx/src/main/java/luyao/util/ktx/ext/SystemServiceExt.kt
@@ -26,7 +26,7 @@ import androidx.core.content.ContextCompat
  * Created by luyao
  * on 2019/7/9 9:17
  */
-inline fun <reified T : Any> Context.getSystemService(): T? =
+inline fun <reified T> Context.getSystemService(): T? =
     ContextCompat.getSystemService(this, T::class.java)
 
 val Context.windowManager get() = getSystemService<WindowManager>()