Now we can drag any viewport but only the viewport that is focused will be draged because if not on x11 the input will be taken until the application is killed

crates/eframe/src/native/run.rs

@@ -1043,6 +1043,7 @@ mod glow_integration {
                         textures_delta,
                         shapes,
                         mut viewports,
+                        viewport_commands,
                     };
 
                     let control_flow;
@@ -1077,6 +1078,7 @@ mod glow_integration {
                             textures_delta,
                             shapes,
                             viewports,
+                            viewport_commands,
                         } = integration.update(
                             app.as_mut(),
                             win.window.as_ref().unwrap(),
@@ -1235,6 +1237,27 @@ mod glow_integration {
                         active_viewports_ids.push(id);
                     }
 
+                    /// TODO Make this more efficient
+                    for (id, command) in viewport_commands {
+                        for window in gl_window.windows.iter() {
+                            if window.window_id == id {
+                                if let Some(win) = &window.window {
+                                    match command {
+                                        egui::window::ViewportCommand::Drag => {
+                                            // if this is not checked on x11 the input will be permanently taken until the app is killed!
+                                            if let Some(focus) = self.is_focused {
+                                                if focus == id {
+                                                    win.drag_window();
+                                                }
+                                            }
+                                        }
+                                    }
+                                }
+                                break;
+                            }
+                        }
+                    }
+
                     gl_window
                         .windows
                         .retain(|w| active_viewports_ids.contains(&w.window_id));

crates/egui/src/containers/window.rs

@@ -143,6 +143,12 @@ impl ViewportBuilder {
     }
 }
 
+#[derive(Clone, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
+pub enum ViewportCommand {
+    Drag,
+}
+
 /// Builder for a floating window which can be dragged, closed, collapsed, resized and scrolled (off by default).
 ///
 /// You can customize:

crates/egui/src/context.rs

@@ -4,7 +4,7 @@ use std::sync::Arc;
 use crate::{
     animation_manager::AnimationManager, data::output::PlatformOutput, frame_state::FrameState,
     input_state::*, layers::GraphicLayers, memory::Options, os::OperatingSystem,
-    output::FullOutput, util::IdTypeMap, TextureHandle, *,
+    output::FullOutput, util::IdTypeMap, window::ViewportCommand, TextureHandle, *,
 };
 use ahash::HashMap;
 use epaint::{mutex::*, stats::*, text::Fonts, TessellationOptions, *};
@@ -190,6 +190,8 @@ struct ContextImpl {
             Arc<Box<dyn Fn(&Context, u64, u64) + Sync + Send>>,
         ),
     >,
+    viewport_commands: Vec<(u64, ViewportCommand)>,
+
     viewport_counter: u64,
     current_rendering_viewport: u64,
     is_desktop: bool,
@@ -1353,6 +1355,7 @@ impl Context {
             textures_delta,
             shapes,
             viewports,
+            viewport_commands: self.write(|ctx| std::mem::take(&mut ctx.viewport_commands)),
         }
     }
 
@@ -1975,6 +1978,10 @@ impl Context {
         self.write(|ctx| ctx.is_desktop = value)
     }
 
+    pub fn viewport_command(&self, id: u64, command: ViewportCommand) {
+        self.write(|ctx| ctx.viewport_commands.push((id, command)))
+    }
+
     pub fn create_viewport(
         &self,
         window_builder: ViewportBuilder,

crates/egui/src/data/output.rs

@@ -2,6 +2,7 @@
 
 use std::sync::Arc;
 
+use crate::window::ViewportCommand;
 use crate::Context;
 use crate::{window::ViewportBuilder, WidgetType};
 
@@ -40,6 +41,8 @@ pub struct FullOutput {
         ViewportBuilder,
         Arc<Box<dyn Fn(&Context, u64, u64) + Sync + Send>>,
     )>,
+
+    pub viewport_commands: Vec<(u64, ViewportCommand)>,
 }
 
 impl FullOutput {
@@ -50,14 +53,16 @@ impl FullOutput {
             repaint_after,
             textures_delta,
             shapes,
-            viewports: mut windows,
+            mut viewports,
+            mut viewport_commands,
         } = newer;
 
         self.platform_output.append(platform_output);
         self.repaint_after = repaint_after; // if the last frame doesn't need a repaint, then we don't need to repaint
         self.textures_delta.append(textures_delta);
         self.shapes = shapes; // Only paint the latest
-        self.viewports.append(&mut windows);
+        self.viewports.append(&mut viewports);
+        self.viewport_commands.append(&mut viewport_commands);
     }
 }
 

examples/hello_world_simple/src/main.rs

@@ -53,15 +53,18 @@ fn main() -> Result<(), eframe::Error> {
                             "Current rendering window: {}",
                             ctx.current_rendering_viewport()
                         ));
+                        if ui.button("Drag").is_pointer_button_down_on() {
+                            ctx.viewport_command(id, egui::window::ViewportCommand::Drag)
+                        }
                     },
                 );
             });
             let clone = window2_embedded.clone();
             let embedded = *window2_embedded.read().unwrap();
             egui::CollapsingHeader::new("Shout Test2").show(ui, |ui| {
-                egui::Window::new("Test2")
-                    .embedded(embedded)
-                    .show(ctx, move |ui, _, parent_id| {
+                egui::Window::new("Test2").embedded(embedded).show(
+                    ctx,
+                    move |ui, id, parent_id| {
                         if ui
                             .checkbox(&mut *clone.write().unwrap(), "Should embedd?")
                             .clicked()
@@ -73,7 +76,12 @@ fn main() -> Result<(), eframe::Error> {
                             "Current rendering window: {}",
                             ctx.current_rendering_viewport()
                         ));
-                    });
+
+                        if ui.button("Drag").is_pointer_button_down_on() {
+                            ctx.viewport_command(id, egui::window::ViewportCommand::Drag)
+                        }
+                    },
+                );
             });
         });
     })