Remove ProgressDialog in AppManager

src/main/scala/com/github/shadowsocks/utils/Utils.scala

@@ -42,6 +42,7 @@ import java.io._
 import java.net._
 import java.security.MessageDigest
 
+import android.animation.{AnimatorListenerAdapter, Animator}
 import android.app.ActivityManager
 import android.content.pm.{ApplicationInfo, PackageManager}
 import android.content.{Context, Intent}
@@ -142,6 +143,16 @@ object Utils {
     toast
   }
 
+  def crossFade(context: Context, from: View, to: View) {
+    def shortAnimTime = context.getResources.getInteger(android.R.integer.config_shortAnimTime)
+    to.setAlpha(0)
+    to.setVisibility(View.VISIBLE)
+    to.animate().alpha(1).setDuration(shortAnimTime)
+    from.animate().alpha(0).setDuration(shortAnimTime).setListener(new AnimatorListenerAdapter {
+      override def onAnimationEnd(animation: Animator) = from.setVisibility(View.GONE)
+    })
+  }
+
   // Blocked > 3 seconds
   def toggleAirplaneMode(context: Context) {
     if (Build.VERSION.SDK_INT >= 17) {