~beikege 1 year, 4 days ago

Windows 11
go 1.21.4
go get gioui.org@event-filters

https://go.dev/play/p/vccxZ9U8B_-

layout.List scrolling not working

~gedw99 1 year, 4 days ago

This is wonderful work and just wanted to say thanks.

Will my code need refactoring ? I assume yes.

I guess eventually the examples will be updated to use this if the proposal passes. Happy to help with it . Is there an example so I get a feel for it ?

~egonelbre 1 year, 3 days ago

Here is some of the refactoring you'll need:

gofmt -w -r "system.DestroyEvent -> app.DestroyEvent" .
gofmt -w -r "system.FrameEvent -> app.FrameEvent" .
gofmt -w -r "layout.NewContext -> app.NewContext" .
gofmt -w -r "op.InvalidateOp{}.Add(gtx.Ops) -> gtx.Execute(op.InvalidateCmd{})" .
goimports -w .

Remove any code related to package "gioui.org/profile"

For gesture.drag:

for _, e := range drag.Update(gtx.Metric, gtx, gesture.Both) {

// ==>

for {
	e, ok := drag.Update(gtx.Metric, gtx.Source, gesture.Both)
	if !ok {
		break
	}

Didn't get further at the moment.

~ajstarks 1 year, 3 days ago*

I updated giocanvas with the new event handling system, (many thanks for the gofmt commands from @egonelbre) and some clients work as expected (modulo the still existing bug #542). I'm not clear on the proper refactoring for clients with more extensive event handling. For example, is the best way to refactor:

case app.FrameEvent:
			canvas := giocanvas.NewCanvas(float32(e.Size.X), float32(e.Size.Y), app.FrameEvent{})
			key.InputOp{Tag: pressed}.Add(canvas.Context.Ops)
			pointer.InputOp{Tag: pressed, Grab: false, Kinds: pointer.Press | pointer.Move}.Add(canvas.Context.Ops)

This:

		case app.FrameEvent:
			canvas := giocanvas.NewCanvas(float32(e.Size.X), float32(e.Size.Y), app.FrameEvent{})
			canvas.Context.Execute(key.FocusCmd{Tag: pressed})
			canvas.Context.Event(pointer.Filter{Kinds: pointer.Press | pointer.Move})

~eliasnaur 1 year, 3 days ago

~beikege: thank you, I've updated the branch to fix widget.List. Use go get gioui.org@cf3e0c744246b4ae to get around Go proxy caching of the branch.

~gedw99: yes, code will need refactoring, but mostly in low-level widget code. I'm using the kitchen example for testing:

diff --git a/kitchen/kitchen.go b/kitchen/kitchen.go
index 10d4c05..da8d2f0 100644
--- a/kitchen/kitchen.go
+++ b/kitchen/kitchen.go
@@ -22,8 +22,7 @@ import (
 	"gioui.org/font/gofont"
 	"gioui.org/gpu/headless"
 	"gioui.org/io/event"
-	"gioui.org/io/router"
-	"gioui.org/io/system"
+	"gioui.org/io/input"
 	"gioui.org/layout"
 	"gioui.org/op"
 	"gioui.org/op/clip"
@@ -96,7 +95,7 @@ func saveScreenshot(f string) error {
 			PxPerSp: scale,
 		},
 		Constraints: layout.Exact(sz),
-		Queue:       new(router.Router),
+		Source:      input.Source{},
 	}
 	th := material.NewTheme()
 	th.Shaper = text.NewShaper(text.WithCollection(gofont.Collection()))
@@ -126,7 +125,7 @@ func loop(w *app.Window) error {
 			ev := w.NextEvent()
 			events <- ev
 			<-acks
-			if _, ok := ev.(system.DestroyEvent); ok {
+			if _, ok := ev.(app.DestroyEvent); ok {
 				return
 			}
 		}
@@ -137,11 +136,11 @@ func loop(w *app.Window) error {
 		select {
 		case e := <-events:
 			switch e := e.(type) {
-			case system.DestroyEvent:
+			case app.DestroyEvent:
 				acks <- struct{}{}
 				return e.Err
-			case system.FrameEvent:
-				gtx := layout.NewContext(&ops, e)
+			case app.FrameEvent:
+				gtx := app.NewContext(&ops, e)
 				if *disable {
 					gtx = gtx.Disabled()
 				}
@@ -170,7 +169,7 @@ func transformedKitchen(gtx layout.Context, th *material.Theme) layout.Dimension
 	if !transformTime.IsZero() {
 		dt := float32(gtx.Now.Sub(transformTime).Seconds())
 		angle := dt * .1
-		op.InvalidateOp{}.Add(gtx.Ops)
+		gtx.Execute(op.InvalidateCmd{})
 		tr := f32.Affine2D{}
 		tr = tr.Rotate(f32.Pt(300, 20), -angle)
 		scale := 1.0 - dt*.5
@@ -332,7 +331,7 @@ func kitchen(gtx layout.Context, th *material.Theme) layout.Dimensions {
 						return material.Clickable(gtx, flatBtn, func(gtx C) D {
 							return layout.UniformInset(unit.Dp(12)).Layout(gtx, func(gtx C) D {
 								flatBtnText := material.Body1(th, "Flat")
-								if gtx.Queue == nil {
+								if !gtx.Enabled() {
 									flatBtnText.Color.A = 150
 								}
 								return layout.Center.Layout(gtx, flatBtnText.Layout)

~ajstarks: I believe this is what you want:

case app.FrameEvent:
    canvas := giocanvas.NewCanvas(float32(e.Size.X), float32(e.Size.Y), app.FrameEvent{})
    event.Op{Tag: pressed}.Add(canvas.Context.Ops)

The pointer.InputOp kinds are replaced with filters at your event handling:

for {
   e, ok := gtx.Event(pointer.Filter{Target: pressed, Kinds: pointer.Press | pointer.Move})
   if !ok { break }
}

~beikege 1 year, 3 days ago

go get gioui.org@cf3e0c744246b4ae

Works perfectly, thank you.

~ajstarks 1 year, 3 days ago

Previously I did this:

var pressed bool
for {
    ev := w.NextEvent() 
    switch e := ev.(type) {
    case app.FrameEvent:
       ....
        kbpointer(e.Queue) // handle key and pointer events
        e.Frame(....)
  }
}

// handle kb and pointer
func kbpointer(q event.Queue) {
    for _, ev := range q.Events(pressed) { 
         if k, ok := ev.(key.Event); ok { ... } // handle kb
         if p, ok := ev.(pointer.Event); ok { ...} // handle pointer
    }
}

What is the best re-factor?

~eliasnaur 1 year, 3 days ago*

Try (untested):

kbpointer(e.Source)
...
// handle kb and pointer
func kbpointer(q input.Source) {
    for {
         e, ok := q.Event(
             key.Filter{},
             pointer.Filter{Target: pressed, Kinds: pointer.Press | pointer.Move | pointer.Release},
         )
         if !ok { break }
         switch e := e.(type) {
         case key.Event:
               // handle kb
         case pointer.Event:
              // handle pointer
         }
    }
}

~beikege 1 year, 3 days ago*

~eliasnaur

https://go.dev/play/p/HFJWhntO9Ua

go get gioui.org@cf3e0c744246b4ae

Android Scrolling the list causes infinite frame refreshes.

Use adb logcat to view logs.

---

go get gioui.org@86fe42a4372c215b

Works perfectly, thank you.

~ajstarks 1 year, 3 days ago

@eliasnaur: thanks for the pointers. I have it mostly working now with a slight correction:

kbpointer(e.Source)
...
// handle kb and pointer
func kbpointer(q input.Source) {
    for {
         e, ok := q.Event( // q.Event, not e.Event
             key.Filter{},
             pointer.Filter{Target: pressed, Kinds: pointer.Press | pointer.Move | pointer.Release},
         )
         if !ok { break }
         switch e := e.(type) {
         case key.Event:
               // handle kb
         case pointer.Event:
              // handle pointer
         }
    }
}

One issue: I cannot turning on modifiers for the key events:

key.Filter{Required: key.ModCtrl}

disables all keyboard events.

~egonelbre 1 year, 2 days ago

Currently I'm unable to figure out how to set cursor for different regions without causing redraws. https://github.com/egonelbre/expgio/blob/event-filters/cursors/main.go#L100.

~eliasnaur 1 year, 2 days ago

~ajstarks: use the Optional field of key.Filter instead of Required.

~ajstarks 1 year, 2 days ago

~eliasnaur, the use of Optional works fine. thanks. Giocanvas and its clients are now converted. Overall the new API seems at bit cleaner and more straightforward.

New: https://gist.github.com/ajstarks/ef633da557c4f90429990d66f0f6c7c6

Old: https://gist.github.com/ajstarks/9224ad09306ecb240c6618bf32da45e6

Diff:

2c2
< func kbpointer(q event.Queue, cfg config) {
---
> func kbpointer(q input.Source, cfg config) {
6,9c6,18
< 	for _, ev := range q.Events(pressed) {
< 		// keyboard events
< 		if k, ok := ev.(key.Event); ok {
< 			switch k.State {
---
> 	for {
> 		e, ok := q.Event(
> 			key.Filter{Optional: key.ModCtrl},
> 			pointer.Filter{Kinds: pointer.Press | pointer.Move | pointer.Release},
> 		)
> 		if !ok {
> 			break
> 		}
> 		switch e := e.(type) {
> 
> 		case key.Event: // keyboard events
> 
> 			switch e.State {
11c20
< 				switch k.Name {
---
> 				switch e.Name {
31c40
< 					switch k.Modifiers {
---
> 					switch e.Modifiers {
38c47
< 					switch k.Modifiers {
---
> 					switch e.Modifiers {
45c54
< 					switch k.Modifiers {
---
> 					switch e.Modifiers {
52c61
< 					switch k.Modifiers {
---
> 					switch e.Modifiers {
62,65c71,74
< 		}
< 		// pointer events
< 		if p, ok := ev.(pointer.Event); ok {
< 			switch p.Kind {
---
> 
> 		case pointer.Event: // pointer events
> 
> 			switch e.Kind {
67c76
< 				mouseX, mouseY = pctcoord(p.Position.X, p.Position.Y, width, height)
---
> 				mouseX, mouseY = pctcoord(e.Position.X, e.Position.Y, width, height)
69c78
< 				switch p.Buttons {
---
> 				switch e.Buttons {
71c80
< 					bx, by = pctcoord(p.Position.X, p.Position.Y, width, height)
---
> 					bx, by = pctcoord(e.Position.X, e.Position.Y, width, height)
73c82
< 					ex, ey = pctcoord(p.Position.X, p.Position.Y, width, height)
---
> 					ex, ey = pctcoord(e.Position.X, e.Position.Y, width, height)
77d85
< 				pressed = true
96c104
< 		case system.DestroyEvent:
---
> 		case app.DestroyEvent:
100,103c108,109
< 		case system.FrameEvent:
< 			canvas := giocanvas.NewCanvas(float32(e.Size.X), float32(e.Size.Y), system.FrameEvent{})
< 			key.InputOp{Tag: pressed}.Add(canvas.Context.Ops)
< 			pointer.InputOp{Tag: pressed, Grab: false, Kinds: pointer.Press | pointer.Move}.Add(canvas.Context.Ops)
---
> 		case app.FrameEvent:
> 			canvas := giocanvas.NewCanvas(float32(e.Size.X), float32(e.Size.Y), app.FrameEvent{})
143c149
< 			kbpointer(e.Queue, cfg)
---
> 			kbpointer(e.Source, cfg)

also in giocanvas abs.go, changed

op.InvalidateOp{}.Add(ops)

to

c.Context.Execute(op.InvalidateCmd{})

~eliasnaur 1 year, 2 days ago*

~beikege: another good catch, thank you. ~egonelbre: thanks, fixed.

go get gioui.org@86fe42a4372c215b should fix both issues.

~gedw99 1 year, 2 days ago

thanks for all the tips. Great community !!

~eliasnaur 1 year, 1 day ago

What do you think of the names introduced? In particular, Source.Event? If it's all good, I shall rename app.Window.NextEvent to match.

~beikege 1 year, 1 day ago

The event exceeds the clipping area.

go get gioui.org@86fe42a4372c215b

https://go.dev/play/p/GweMCrv5A9x

~jeffwilliams a year ago

I believe the documentation for app.NewContext needs updating. It mentions:

    NewContext is shorthand for

        layout.Context{
          Ops: ops,
          Now: e.Now,
          Queue: e.Queue,
          Config: e.Config,
          Constraints: layout.Exact(e.Size),
        }

However FrameEvent no longer has some of the fields mentioned:

type FrameEvent struct {
	// Now is the current animation. Use Now instead of time.Now to
	// synchronize animation and to avoid the time.Now call overhead.
	Now time.Time
	// Metric converts device independent dp and sp to device pixels.
	Metric unit.Metric
	// Size is the dimensions of the window.
	Size image.Point
	// Insets represent the space occupied by system decorations and controls.
	Insets Insets
	// Frame completes the FrameEvent by drawing the graphical operations
	// from ops into the window.
	Frame func(frame *op.Ops)
	// Source is the interface between the window and widgets.
	Source input.Source
}

~jeffwilliams a year ago

I'm trying to think of how I can refactor some code to work with the new event delivery model, and I wonder if someone might have a suggestion. Previously, I had code like the following:

func loop(w *app.Window) error {
...
	for {
		select {
		case e := <-w.Events():
			err := handleEvent(e)
			if err != nil {
				return err
			}
		case w := <-editor.WorkChan():
			w.Service()
		}
	}
	

This has been slightly simplified to demonstrate the main problem.

The idea is that I have a select statement that will either handle UI events (the w.Events() case), or perform a unit of work that was requested by a different goroutine (the editor.WorkChan() case). The units of work usually modify the same datastructures and state that the handlers for the UI events also modify.

With the new model there is no channel to select for events and the function that returns the next event is blocking, which means that if the program blocked on Window.NextEvent() then editor.WorkChan() cannot be serviced. Can I call Window.NextEvent() from a separate goroutine? In which case I could do something like:

	events := make(chan event.Event)
	go func() {
		for {
			events <- w.NextEvent()
		}
	}()

	for {
		select {
		case e := <-events:
			err := handleEvent(e)
			if err != nil {
				return err
			}
		case w := <-editor.WorkChan():
			w.Service()
		}
	}

Assuming I cannot, is there a way that my program can inject custom events so that w.NextEvent() would return them, or some other method? I'd like to avoid having some sort of global mutex for the program datastructures.

~eliasnaur a year ago

~jeffwilliams: updated documentation, thanks. ~whereswaldon covers the options for refactoring channel-based events loops in his latest newsletter[0]. ~beikege: another great find, thanks (the issue was the unexpected nil pointer.Filter.Target). Fixed and added test.

Latest version: go get gioui.org@7392d2ff

[0] https://gioui.org/news/2023-11#api-change-window-event-iteration

~beikege a year ago

~eliasnaur

go get gioui.org@7392d2ff

Unable to receive any pointer events.

https://go.dev/play/p/GweMCrv5A9x

~eliasnaur a year ago

Yes, you need to fill out the pointer.Filter.Target field to receive events:

pointer.Filter{Target: l, Kinds: pointer.Press | pointer.Drag | pointer.Release | pointer.Cancel},

Before my fix, nil targets would work by accident.

~beikege a year ago

Thanks, works perfectly.

~jeffwilliams 11 months ago

~eliasnaur: Thanks, I think the last method in the newsletter should work. I found one more minor documentation bug. The documentation for io/clipboard.ReadCmd reads "ReadCmd requests the text of the clipboard, delivered to the handler through an op/transfer.DataEvent", but I think it should instead be io/transfer.DataEvent if I am not mistaken.

~eliasnaur 11 months ago

~jeffwilliams: thanks, fixed in ab776c65.

~eliasnaur referenced this from #553 11 months ago

~andybalholm referenced this from #553 11 months ago

~eliasnaur referenced this from #555 11 months ago

~whereswaldon 10 months ago

In the conversion of gio-x to this API, I encountered what I think is a bug. The follow program defines a whole-window area that listens for clicks and key events. If it is clicked, it tries to transfer keyboard focus to itself. However, keyboard focus transfer never occurs. Either I've misunderstood the API, or there's something swallowing the focus transfer:

// SPDX-License-Identifier: Unlicense OR MIT

package main

// A simple Gio program. See https://gioui.org for more information.

import (
	"fmt"
	"log"
	"os"

	"gioui.org/app"
	"gioui.org/io/event"
	"gioui.org/io/key"
	"gioui.org/io/pointer"
	"gioui.org/op"
)

func main() {
	go func() {
		w := app.NewWindow()
		if err := loop(w); err != nil {
			log.Fatal(err)
		}
		os.Exit(0)
	}()
	app.Main()
}

func loop(w *app.Window) error {
	tag := new(int)
	var ops op.Ops
	for {
		switch e := w.NextEvent().(type) {
		case app.DestroyEvent:
			return e.Err
		case app.FrameEvent:
			gtx := app.NewContext(&ops, e)
			for {
				ev, ok := gtx.Source.Event(pointer.Filter{
					Target: tag,
					Kinds:  pointer.Release,
				})
				if !ok {
					break
				}
				switch ev := ev.(type) {
				case pointer.Event:
					if ev.Kind == pointer.Release {
						gtx.Execute(key.FocusCmd{Tag: tag})
						fmt.Println("triggered focus command")
					}
				}
				fmt.Printf("%#+v\n", ev)
			}
			for {
				ev, ok := gtx.Source.Event(key.Filter{
					Focus: tag,
				})
				if !ok {
					break
				}
				fmt.Printf("%#+v\n", ev)
			}
			event.Op(gtx.Ops, tag)
			e.Frame(gtx.Ops)
		}
	}
}

~eliasnaur 9 months ago*

The issue is caused by an unfortunate combination:

• You don't include key.FocusFilter for matching key.FocusEvents, which means your tag won't be considered a valid focus target.
• key.Filter.Focus is for matching key events only if the specified tag is focused (e.g. an Editor is not interested in arrow keys when not focused).

I'm not sure what the right fix is. It's tempting to say that tags mentioned in key.Filter.Focus are also focusable, but that seems too subtle.

~whereswaldon 9 months ago

Thanks for the clarification; I had missed that requesting focusability was a separate filter type. I'm not sure if this really needs a fix. I was just holding it wrong.

~whereswaldon 9 months ago

Now that input.Router.Queue does not return a boolean indicating whether the event has a handler, how should custom rendering applications detect that Gio isn't handling an event? I'm trying to convert the glfw and opengl examples, both of which need this. I could register some kind of catch-all event handler to detect it, but I'm not sure that's the proper approach.

~whereswaldon 9 months ago

gioui.org/x and gioui.org/example now also have event-filters branches that are updated to be compatible with core's event-filters branch. My only API concern is the one I mention above about custom rendering event processing.

~eliasnaur 9 months ago

~whereswaldon: For app.Window I replaced the bool result with a call to Router.WakeupTime() that aggregates all the reasons for generating a new frame. Would that work for glfw and opengl?

Note: I've force-pushed event-filters with a few documentation fixes.

~whereswaldon 9 months ago

That does indeed seem to work; thank you!

~whereswaldon 9 months ago

Now that the whole ecosystem supports it, I'm going to merge event-filters and tag a new release

~whereswaldon REPORTED CLOSED 9 months ago

Release is out; this issue can be closed.