From 59ed15b2f746c234757c64265a274d08ecfbb27a Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Thu, 15 Jan 2015 22:28:05 +0900
Subject: [PATCH] Bug fix: Use prevent default properly

---
 internal/ui/ui_js.go | 37 ++++++++++---------------------------
 1 file changed, 10 insertions(+), 27 deletions(-)

diff --git a/internal/ui/ui_js.go b/internal/ui/ui_js.go
index a6efeffbf..d4151d4fa 100644
--- a/internal/ui/ui_js.go
+++ b/internal/ui/ui_js.go
@@ -81,23 +81,6 @@ func init() {
 		})
 		<-ch
 	}
-	doc.Call("addEventListener", "keydown", func(e js.Object) bool {
-		code := e.Get("keyCode").Int()
-		// Backspace
-		if code == 8 {
-			return false
-		}
-		// Functions
-		if 112 <= code && code <= 123 {
-			return false
-		}
-		// Alt and arrows
-		if code == 37 && code == 39 {
-			// Don't need to check Alt.
-			return false
-		}
-		return true
-	})
 
 	canvas = doc.Call("createElement", "canvas")
 	canvas.Set("width", 16)
@@ -136,30 +119,30 @@ func init() {
 	canvas.Get("style").Set("outline", "none")
 
 	// Keyboard
-	canvas.Call("addEventListener", "keydown", func(e js.Object) bool {
+	canvas.Call("addEventListener", "keydown", func(e js.Object) {
+		e.Call("preventDefault")
 		code := e.Get("keyCode").Int()
 		currentInput.keyDown(code)
-		return false
 	})
-	canvas.Call("addEventListener", "keyup", func(e js.Object) bool {
+	canvas.Call("addEventListener", "keyup", func(e js.Object) {
+		e.Call("preventDefault")
 		code := e.Get("keyCode").Int()
 		currentInput.keyUp(code)
-		return false
 	})
 
 	// Mouse
-	canvas.Call("addEventListener", "mousedown", func(e js.Object) bool {
+	canvas.Call("addEventListener", "mousedown", func(e js.Object) {
+		e.Call("preventDefault")
 		button := e.Get("button").Int()
 		currentInput.mouseDown(button)
-		return false
 	})
-	canvas.Call("addEventListener", "mouseup", func(e js.Object) bool {
+	canvas.Call("addEventListener", "mouseup", func(e js.Object) {
+		e.Call("preventDefault")
 		button := e.Get("button").Int()
 		currentInput.mouseUp(button)
-		return false
 	})
-	canvas.Call("addEventListener", "contextmenu", func(e js.Object) bool {
-		return false
+	canvas.Call("addEventListener", "contextmenu", func(e js.Object) {
+		e.Call("preventDefault")
 	})
 
 	// Gamepad