vxfw: remove handles_mouse from Surface

Don't require that surfaces explicitly declare mouse handling. We either
pass an event to the eventHandler or we don't. Along with this, we
remove all native widget passthrough events (IE we never pass an event
to a child). Native widgets which don't handle events also set
eventHandler to null, which prevents any null pointer issues also

src/vxfw/Button.zig

@@ -110,7 +110,6 @@ pub fn draw(self: *Button, ctx: vxfw.DrawContext) Allocator.Error!vxfw.Surface {
 
     var button_surf = try vxfw.Surface.initWithChildren(ctx.arena, self.widget(), surf.size, surf.children);
     @memset(button_surf.buffer, .{ .style = style });
-    button_surf.handles_mouse = true;
     button_surf.focusable = true;
     return button_surf;
 }

src/vxfw/Center.zig

@@ -12,16 +12,10 @@ child: vxfw.Widget,
 pub fn widget(self: *const Center) vxfw.Widget {
     return .{
         .userdata = @constCast(self),
-        .eventHandler = typeErasedEventHandler,
         .drawFn = typeErasedDrawFn,
     };
 }
 
-fn typeErasedEventHandler(ptr: *anyopaque, ctx: *vxfw.EventContext, event: vxfw.Event) anyerror!void {
-    const self: *const Center = @ptrCast(@alignCast(ptr));
-    return self.child.handleEvent(ctx, event);
-}
-
 fn typeErasedDrawFn(ptr: *anyopaque, ctx: vxfw.DrawContext) Allocator.Error!vxfw.Surface {
     const self: *const Center = @ptrCast(@alignCast(ptr));
     return self.draw(ctx);

src/vxfw/ListView.zig

@@ -109,20 +109,6 @@ pub fn handleEvent(self: *ListView, ctx: *vxfw.EventContext, event: vxfw.Event)
                 self.ensureScroll();
                 return ctx.consumeAndRedraw();
             }
-
-            // All other keypresses go to our focused child
-            switch (self.children) {
-                .slice => |slice| {
-                    if (slice.len == 0) return;
-                    const child = slice[self.cursor];
-                    return child.handleEvent(ctx, event);
-                },
-                .builder => |builder| {
-                    if (builder.itemAtIdx(self.cursor, self.cursor)) |child| {
-                        return child.handleEvent(ctx, event);
-                    }
-                },
-            }
         },
         else => {},
     }
@@ -307,7 +293,6 @@ fn drawBuilder(self: *ListView, ctx: vxfw.DrawContext, builder: Builder) Allocat
     // Set state
     {
         surface.focusable = true;
-        surface.handles_mouse = true;
         // Assume we have more. We only know we don't after drawing
         self.scroll.has_more = true;
     }

src/vxfw/Padding.zig

@@ -43,16 +43,10 @@ pub fn vertical(padding: u16) PadValues {
 pub fn widget(self: *const Padding) vxfw.Widget {
     return .{
         .userdata = @constCast(self),
-        .eventHandler = typeErasedEventHandler,
         .drawFn = typeErasedDrawFn,
     };
 }
 
-fn typeErasedEventHandler(ptr: *anyopaque, ctx: *vxfw.EventContext, event: vxfw.Event) anyerror!void {
-    const self: *const Padding = @ptrCast(@alignCast(ptr));
-    return self.child.handleEvent(ctx, event);
-}
-
 fn typeErasedDrawFn(ptr: *anyopaque, ctx: vxfw.DrawContext) Allocator.Error!vxfw.Surface {
     const self: *const Padding = @ptrCast(@alignCast(ptr));
     return self.draw(ctx);

src/vxfw/SizedBox.zig

@@ -13,16 +13,10 @@ size: vxfw.Size,
 pub fn widget(self: *const SizedBox) vxfw.Widget {
     return .{
         .userdata = @constCast(self),
-        .eventHandler = typeErasedEventHandler,
         .drawFn = typeErasedDrawFn,
     };
 }
 
-fn typeErasedEventHandler(ptr: *anyopaque, ctx: *vxfw.EventContext, event: vxfw.Event) anyerror!void {
-    const self: *const SizedBox = @ptrCast(@alignCast(ptr));
-    return self.child.handleEvent(ctx, event);
-}
-
 fn typeErasedDrawFn(ptr: *anyopaque, ctx: vxfw.DrawContext) Allocator.Error!vxfw.Surface {
     const self: *const SizedBox = @ptrCast(@alignCast(ptr));
     const max: vxfw.MaxSize = .{

src/vxfw/SplitView.zig

@@ -129,7 +129,6 @@ fn typeErasedDrawFn(ptr: *anyopaque, ctx: vxfw.DrawContext) Allocator.Error!vxfw
     }
 
     var surface = try vxfw.Surface.initWithChildren(ctx.arena, self.widget(), max, &self.children);
-    surface.handles_mouse = true;
     for (0..max.height) |row| {
         surface.writeCell(self.width + 1, @intCast(row), .{
             .char = .{ .grapheme = "│", .width = 1 },

src/vxfw/TextField.zig

@@ -207,7 +207,6 @@ pub fn draw(self: *TextField, ctx: vxfw.DrawContext) Allocator.Error!vxfw.Surfac
         .{ .width = max_width, .height = @max(ctx.min.height, 1) },
     );
     surface.focusable = true;
-    surface.handles_mouse = true;
 
     const base: vaxis.Cell = .{ .style = .{} };
     @memset(surface.buffer, base);

src/vxfw/vxfw.zig

@@ -267,8 +267,6 @@ pub const Surface = struct {
 
     /// If this widget / Surface is focusable
     focusable: bool = false,
-    /// If this widget can handle mouse events
-    handles_mouse: bool = false,
 
     /// Cursor state
     cursor: ?CursorState = null,
@@ -332,7 +330,6 @@ pub const Surface = struct {
             .buffer = self.buffer[0 .. self.size.width * height],
             .children = self.children,
             .focusable = self.focusable,
-            .handles_mouse = self.handles_mouse,
         };
     }
 
@@ -340,8 +337,7 @@ pub const Surface = struct {
     /// always be translated to local Surface coordinates. Asserts that this Surface does contain Point
     pub fn hitTest(self: Surface, list: *std.ArrayList(HitResult), point: Point) Allocator.Error!void {
         assert(point.col < self.size.width and point.row < self.size.height);
-        if (self.handles_mouse)
+        try list.append(.{ .local = point, .widget = self.widget });
-            try list.append(.{ .local = point, .widget = self.widget });
         for (self.children) |child| {
             if (!child.containsPoint(point)) continue;
             const child_point: Point = .{