ui/app,cmd/gio: move running of main from driver to GioAppDelegate

Signed-off-by: Elias Naur <mail@eliasnaur.com>

cmd/gio/iosbuild.go

@@ -139,11 +139,8 @@ func exeIOS(tmpDir, target, app string, bi *buildInfo) error {
 	const mainmSrc = `@import UIKit;
 @import Gio;
 
-void gio_runMain(void);
-
 int main(int argc, char * argv[]) {
 	@autoreleasepool {
-		gio_runMain();
 		return UIApplicationMain(argc, argv, nil, NSStringFromClass([GioAppDelegate class]));
 	}
 }`

ui/app/os_ios.m

@@ -34,6 +34,8 @@ static void redraw(CFTypeRef viewRef, BOOL sync) {
 
 @implementation GioAppDelegate
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+	gio_runMain();
+
 	self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
 	GioViewController *controller = [[GioViewController alloc] initWithNibName:nil bundle:nil];
 	controller.screen = self.window.screen;

ui/app/runmain.go

@@ -7,16 +7,21 @@ package app
 // library mode. To make Gio programs simpler and uniform, we'll
 // link to the main function here and call it from Java.
 
-import _ "unsafe" // for go:linkname
+import (
+	"sync"
+	_ "unsafe" // for go:linkname
+)
 
 //go:linkname mainMain main.main
 func mainMain()
 
+var runMainOnce sync.Once
+
 func runMain() {
-	go func() {
+	runMainOnce.Do(func() {
 		// Indirect call, since the linker does not know the address of main when
 		// laying down this package.
 		fn := mainMain
-		fn()
-	}()
+		go fn()
+	})
 }