Fixed fab animation on user screen

app/src/main/java/me/vadik/knigopis/extensions.kt

@@ -11,6 +11,8 @@ import android.support.annotation.DimenRes
 import android.support.annotation.LayoutRes
 import android.support.annotation.StringRes
 import android.support.v4.view.ViewCompat
+import android.support.v4.view.animation.FastOutLinearInInterpolator
+import android.support.v4.view.animation.LinearOutSlowInInterpolator
 import android.text.Html
 import android.text.Spanned
 import android.util.Log
@@ -119,13 +121,28 @@ fun View.show(value: Boolean) {
 fun View.show() {
     animate().alpha(1f).setDuration(200)
         .withStartAction { visibility = View.VISIBLE }
-        .start()
 }
 
 fun View.hide() {
     animate().alpha(0f).setDuration(200)
         .withEndAction { visibility = View.GONE }
-        .start()
+}
+
+fun View.showScale() {
+    alpha = 0f
+    scaleX = 0f
+    scaleY = 0f
+    animate().alpha(1f).setDuration(200)
+        .scaleX(1f).scaleY(1f)
+        .setInterpolator(LinearOutSlowInInterpolator())
+        .withStartAction { visibility = View.VISIBLE }
+}
+
+fun View.hideScale() {
+    animate().alpha(0f).setDuration(200)
+        .scaleX(0f).scaleY(0f)
+        .setInterpolator(FastOutLinearInInterpolator())
+        .withEndAction { visibility = View.GONE }
 }
 
 val View.isVisible get() = visibility == View.VISIBLE

app/src/main/java/me/vadik/knigopis/user/UserActivity.kt

@@ -48,14 +48,14 @@ class UserActivity : AppCompatActivity() {
         toolbarImage.setElevationRes(R.dimen.image_view_elevation)
         setSupportActionBar(toolbar)
         fab.setOnClickListener { view ->
-            fab.hide()
+            fab.hideScale()
             api.createSubscription(userId, auth.getAccessToken())
                 .io2main()
                 .subscribe({
                     Snackbar.make(view, "Successfully subscribed", Snackbar.LENGTH_LONG)
                         .setAction("Action", null).show()
                 }, {
-                    fab.show()
+                    fab.showScale()
                     logError("Cannot update subscription", it)
                 })
         }
@@ -90,7 +90,7 @@ class UserActivity : AppCompatActivity() {
             .io2main()
             .subscribe({ subscriptions ->
                 if (subscriptions.none { it.subUser.id == userId }) {
-                    fab.show()
+                    fab.showScale()
                 } else {
                     unsubscribeOption.isVisible = true
                 }