From e46b0018b99aef59be822ba09a1751888b6734da Mon Sep 17 00:00:00 2001
From: Garoven <95014675+Garoven@users.noreply.github.com>
Date: Mon, 22 Jan 2024 12:13:28 +0100
Subject: [PATCH] Fix Android crash on resume (#3847)

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Added Viewport reinitialization and Window recreation for Android on
resume event.

Closes <https://github.com/emilk/egui/issues/3674>.


https://github.com/emilk/egui/assets/95014675/7bc51ea5-3f63-4422-b5a0-ce8291612982
---
 crates/eframe/src/native/wgpu_integration.rs | 28 ++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/crates/eframe/src/native/wgpu_integration.rs b/crates/eframe/src/native/wgpu_integration.rs
index 79e94e52..56847b92 100644
--- a/crates/eframe/src/native/wgpu_integration.rs
+++ b/crates/eframe/src/native/wgpu_integration.rs
@@ -139,6 +139,32 @@ impl WgpuWinitApp {
         }
     }
 
+    #[cfg(target_os = "android")]
+    fn recreate_window(
+        &self,
+        event_loop: &EventLoopWindowTarget<UserEvent>,
+        running: &WgpuWinitRunning,
+    ) {
+        let SharedState {
+            egui_ctx,
+            viewports,
+            viewport_from_window,
+            painter,
+            ..
+        } = &mut *running.shared.borrow_mut();
+
+        initialize_or_update_viewport(
+            egui_ctx,
+            viewports,
+            ViewportIdPair::ROOT,
+            ViewportClass::Root,
+            self.native_options.viewport.clone(),
+            None,
+            None,
+        )
+        .initialize_window(event_loop, egui_ctx, viewport_from_window, painter);
+    }
+
     #[cfg(target_os = "android")]
     fn drop_window(&mut self) -> Result<(), egui_wgpu::WgpuError> {
         if let Some(running) = &mut self.running {
@@ -386,6 +412,8 @@ impl WinitApp for WgpuWinitApp {
                 log::debug!("Event::Resumed");
 
                 let running = if let Some(running) = &self.running {
+                    #[cfg(target_os = "android")]
+                    self.recreate_window(event_loop, running);
                     running
                 } else {
                     let storage = epi_integration::create_storage(