Introduce `on_click` handler in `PaneGrid`

examples/pane_grid/Cargo.toml

@@ -6,4 +6,4 @@ edition = "2018"
 publish = false
 
 [dependencies]
-iced = { path = "../.." }
+iced = { path = "../..", features = ["debug"] }

examples/pane_grid/src/main.rs

@@ -19,6 +19,7 @@ enum Message {
     Split(pane_grid::Axis, pane_grid::Pane),
     SplitFocused(pane_grid::Axis),
     FocusAdjacent(pane_grid::Direction),
+    Clicked(pane_grid::Pane),
     Dragged(pane_grid::DragEvent),
     Resized(pane_grid::ResizeEvent),
     Close(pane_grid::Pane),
@@ -45,22 +46,30 @@ impl Sandbox for Example {
     fn update(&mut self, message: Message) {
         match message {
             Message::Split(axis, pane) => {
-                let _ = self.panes.split(
+                let result = self.panes.split(
                     axis,
                     &pane,
                     Content::new(self.panes_created),
                 );
 
+                if let Some((pane, _)) = result {
+                    self.focus = Some(pane);
+                }
+
                 self.panes_created += 1;
             }
             Message::SplitFocused(axis) => {
                 if let Some(pane) = self.focus {
-                    let _ = self.panes.split(
+                    let result = self.panes.split(
                         axis,
                         &pane,
                         Content::new(self.panes_created),
                     );
 
+                    if let Some((pane, _)) = result {
+                        self.focus = Some(pane);
+                    }
+
                     self.panes_created += 1;
                 }
             }
@@ -73,6 +82,9 @@ impl Sandbox for Example {
                     }
                 }
             }
+            Message::Clicked(pane) => {
+                self.focus = Some(pane);
+            }
             Message::Resized(pane_grid::ResizeEvent { split, ratio }) => {
                 self.panes.resize(&split, ratio);
             }
@@ -113,6 +125,7 @@ impl Sandbox for Example {
         .width(Length::Fill)
         .height(Length::Fill)
         .spacing(10)
+        .on_click(Message::Clicked)
         .on_drag(Message::Dragged)
         .on_resize(10, Message::Resized);
 

native/src/widget/pane_grid.rs

@@ -92,6 +92,7 @@ pub struct PaneGrid<'a, Message, Renderer: self::Renderer> {
     width: Length,
     height: Length,
     spacing: u16,
+    on_click: Option<Box<dyn Fn(Pane) -> Message + 'a>>,
     on_drag: Option<Box<dyn Fn(DragEvent) -> Message + 'a>>,
     on_resize: Option<(u16, Box<dyn Fn(ResizeEvent) -> Message + 'a>)>,
 }
@@ -126,6 +127,7 @@ where
             width: Length::Fill,
             height: Length::Fill,
             spacing: 0,
+            on_click: None,
             on_drag: None,
             on_resize: None,
         }
@@ -155,6 +157,19 @@ where
         self
     }
 
+    /// Sets the message that will be produced when a [`Pane`] of the
+    /// [`PaneGrid`] is clicked.
+    ///
+    /// [`Pane`]: struct.Pane.html
+    /// [`PaneGrid`]: struct.PaneGrid.html
+    pub fn on_click<F>(mut self, f: F) -> Self
+    where
+        F: 'a + Fn(Pane) -> Message,
+    {
+        self.on_click = Some(Box::new(f));
+        self
+    }
+
     /// Enables the drag and drop interactions of the [`PaneGrid`], which will
     /// use the provided function to produce messages.
     ///
@@ -203,21 +218,21 @@ where
             );
 
         if let Some(((pane, content), layout)) = clicked_region.next() {
-            match &self.on_drag {
+            if let Some(on_click) = &self.on_click {
-                Some(on_drag) => {
+                messages.push(on_click(*pane));
-                    if content.can_be_picked_at(layout, cursor_position) {
+            }
-                        let pane_position = layout.position();
 
-                        let origin = cursor_position
+            if let Some(on_drag) = &self.on_drag {
-                            - Vector::new(pane_position.x, pane_position.y);
+                if content.can_be_picked_at(layout, cursor_position) {
+                    let pane_position = layout.position();
 
-                        self.state.pick_pane(pane, origin);
+                    let origin = cursor_position
+                        - Vector::new(pane_position.x, pane_position.y);
 
-                        messages
+                    self.state.pick_pane(pane, origin);
-                            .push(on_drag(DragEvent::Picked { pane: *pane }));
+
-                    }
+                    messages.push(on_drag(DragEvent::Picked { pane: *pane }));
                 }
-                None => {}
             }
         }
     }