From 167d21ec46203b1d44208b864f8ac04b8cd57e92 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sat, 5 May 2018 03:15:17 +0900
Subject: [PATCH] devicescale: Panic on Android when called from init funcs

---
 internal/devicescale/impl_android.go | 2 +-
 run.go                               | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/internal/devicescale/impl_android.go b/internal/devicescale/impl_android.go
index 15d6954c2..3db01425c 100644
--- a/internal/devicescale/impl_android.go
+++ b/internal/devicescale/impl_android.go
@@ -65,7 +65,7 @@ import (
 
 func impl() float64 {
 	if !jni.IsJVMAvailable() {
-		return 0
+		panic("devicescale: JVM is not available yet: is this called from init funcitons?")
 	}
 	s := 0.0
 	if err := jni.RunOnJVM(func(vm, env, ctx uintptr) error {
diff --git a/run.go b/run.go
index 8e988e3b2..fff07362e 100644
--- a/run.go
+++ b/run.go
@@ -502,8 +502,7 @@ func SetWindowIcon(iconImages []image.Image) {
 // DeviceScaleFactor returns a meaningful value on high-DPI display environment,
 // otherwise DeviceScaleFactor returns 1.
 //
-// DeviceScaleFactor might return 0 on init function on some devices like Android.
-// Don't expect DeviceScaleFactor returns a valid value until main starts.
+// DeviceScaleFactor might panic on init function on some devices like Android.
 // Then, it is not recommended to call DeviceScaleFactor from init functions.
 //
 // DeviceScaleFactor is concurrent-safe.