From dc48249e1acea54b391f53b95f16e515dead7c97 Mon Sep 17 00:00:00 2001 From: "Andrew Gallant (Ocelot)" Date: Mon, 7 May 2012 04:09:19 -0400 Subject: lots of docs and examples --- nexgb/examples/atom.go | 27 --------- nexgb/examples/create-window/main.go | 98 ++++++++++++++++++++++++++++++++ nexgb/examples/doc.go | 21 +++++++ nexgb/examples/get-active-window/main.go | 57 +++++++++++++++++++ nexgb/examples/property.go | 41 ------------- nexgb/examples/randr.go | 48 ---------------- nexgb/examples/randr/main.go | 84 +++++++++++++++++++++++++++ nexgb/examples/seq-nowrap.go | 29 ---------- nexgb/examples/seq-wrap.go | 24 -------- nexgb/examples/window.go | 61 -------------------- nexgb/examples/xinerama.go | 29 ---------- nexgb/examples/xinerama/main.go | 39 +++++++++++++ 12 files changed, 299 insertions(+), 259 deletions(-) delete mode 100644 nexgb/examples/atom.go create mode 100644 nexgb/examples/create-window/main.go create mode 100644 nexgb/examples/doc.go create mode 100644 nexgb/examples/get-active-window/main.go delete mode 100644 nexgb/examples/property.go delete mode 100644 nexgb/examples/randr.go create mode 100644 nexgb/examples/randr/main.go delete mode 100644 nexgb/examples/seq-nowrap.go delete mode 100644 nexgb/examples/seq-wrap.go delete mode 100644 nexgb/examples/window.go delete mode 100644 nexgb/examples/xinerama.go create mode 100644 nexgb/examples/xinerama/main.go (limited to 'nexgb/examples') diff --git a/nexgb/examples/atom.go b/nexgb/examples/atom.go deleted file mode 100644 index 2cb7132..0000000 --- a/nexgb/examples/atom.go +++ /dev/null @@ -1,27 +0,0 @@ -package main - -import ( - // "fmt" - "log" - - "github.com/BurntSushi/xgb" -) - -func init() { - log.SetFlags(0) -} - -func main() { - X, err := xgb.NewConn() - if err != nil { - log.Fatal(err) - } - - aname := "_NET_ACTIVE_WINDOW" - atom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() - if err != nil { - log.Fatal(err) - } - log.Printf("%d", atom.Atom) -} - diff --git a/nexgb/examples/create-window/main.go b/nexgb/examples/create-window/main.go new file mode 100644 index 0000000..6996f37 --- /dev/null +++ b/nexgb/examples/create-window/main.go @@ -0,0 +1,98 @@ +// Example create-window shows how to create a window, map it, resize it, +// and listen to structure and key events (i.e., when the window is resized +// by the window manager, or when key presses/releases are made when the +// window has focus). The events are printed to stdout. +package main + +import ( + "fmt" + + "github.com/BurntSushi/xgb" +) + +func main() { + X, err := xgb.NewConn() + if err != nil { + fmt.Println(err) + return + } + + // Any time a new resource (i.e., a window, pixmap, graphics context, etc.) + // is created, we need to generate a resource identifier with NewId. + wid, _ := X.NewId() + + // CreateWindow takes a boatload of parameters. + X.CreateWindow(X.DefaultScreen().RootDepth, wid, X.DefaultScreen().Root, + 0, 0, 500, 500, 0, + xgb.WindowClassInputOutput, X.DefaultScreen().RootVisual, + 0, []uint32{}) + + // This call to ChangeWindowAttributes could be factored out and + // included with the above CreateWindow call, but it is left here for + // instructive purposes. It tells X to send us events when the 'structure' + // of the window is changed (i.e., when it is resized, mapped, unmapped, + // etc.) and when a key press or a key release has been made when the + // window has focus. + // We also set the 'BackPixel' to white so that the window isn't butt ugly. + X.ChangeWindowAttributes(wid, + xgb.CwBackPixel|xgb.CwEventMask, + []uint32{ // values must be in the order defined by the protocol + 0xffffffff, + xgb.EventMaskStructureNotify | + xgb.EventMaskKeyPress | + xgb.EventMaskKeyRelease}) + + // MapWindow makes the window we've created appear on the screen. + // We demonstrated the use of a 'checked' request here. + // A checked request is a fancy way of saying, "do error handling + // synchronously." Namely, if there is a problem with the MapWindow request, + // we'll get the error *here*. If we were to do a normal unchecked + // request (like the above CreateWindow and ChangeWindowAttributes + // requests), then we would only see the error arrive in the main event + // loop. + // + // Typically, checked requests are useful when you need to make sure they + // succeed. Since they are synchronous, they incur a round trip cost before + // the program can continue, but this is only going to be noticeable if + // you're issuing tons of requests in succession. + // + // Note that requests without replies are by default unchecked while + // requests *with* replies are checked by default. + err = X.MapWindowChecked(wid).Check() + if err != nil { + fmt.Printf("Checked Error for mapping window %d: %s\n", wid, err) + } else { + fmt.Printf("Map window %d successful!\n", wid) + } + + // This is an example of an invalid MapWindow request and what an error + // looks like. + err = X.MapWindowChecked(0).Check() + if err != nil { + fmt.Printf("Checked Error for mapping window 0x1: %s\n", err) + } else { // neva + fmt.Printf("Map window 0x1 successful!\n") + } + + // Start the main event loop. + for { + // WaitForEvent either returns an event or an error and never both. + // If both are nil, then something went wrong and the loop should be + // halted. + // + // An error can only be seen here as a response to an unchecked + // request. + ev, xerr := X.WaitForEvent() + if ev == nil && xerr == nil { + fmt.Println("Both event and error are nil. Exiting...") + return + } + + if ev != nil { + fmt.Printf("Event: %s\n", ev) + } + if xerr != nil { + fmt.Printf("Error: %s\n", xerr) + } + } +} diff --git a/nexgb/examples/doc.go b/nexgb/examples/doc.go new file mode 100644 index 0000000..80ea5b7 --- /dev/null +++ b/nexgb/examples/doc.go @@ -0,0 +1,21 @@ +/* +Package examples contains a few different use cases of XGB, like creating +a window, reading properties, and querying for information about multiple +heads using the Xinerama or RandR extensions. + +If you're looking to get started quickly, I recommend checking out the +create-window example first. It is the most documented and probably covers +some of the more common bare bones cases of creating windows and responding +to events. + +If you're looking to query information about your window manager, +get-active-window is a start. However, to do anything extensive requires +a lot of boiler plate. To that end, I'd recommend use of my higher level +library, xgbutil: https://github.com/BurntSushi/xgbutil + +There are also examples of using the Xinerama and RandR extensions, if you're +interested in querying information about your active heads. In RandR's case, +you can also reconfigure your heads, but the example doesn't cover that. + +*/ +package documentation diff --git a/nexgb/examples/get-active-window/main.go b/nexgb/examples/get-active-window/main.go new file mode 100644 index 0000000..e90563c --- /dev/null +++ b/nexgb/examples/get-active-window/main.go @@ -0,0 +1,57 @@ +// Example get-active-window reads the _NET_ACTIVE_WINDOW property of the root +// window and uses the result (a window id) to get the name of the window. +package main + +import ( + "fmt" + "log" + + "github.com/BurntSushi/xgb" +) + +func main() { + X, err := xgb.NewConn() + if err != nil { + log.Fatal(err) + } + + // Get the window id of the root window. + root := X.DefaultScreen().Root + + // Get the atom id (i.e., intern an atom) of "_NET_ACTIVE_WINDOW". + aname := "_NET_ACTIVE_WINDOW" + activeAtom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() + if err != nil { + log.Fatal(err) + } + + // Get the atom id (i.e., intern an atom) of "_NET_WM_NAME". + aname = "_NET_WM_NAME" + nameAtom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() + if err != nil { + log.Fatal(err) + } + + // Get the actual value of _NET_ACTIVE_WINDOW. + // Note that 'reply.Value' is just a slice of bytes, so we use an + // XGB helper function, 'Get32', to pull an unsigned 32-bit integer out + // of the byte slice. We then convert it to an X resource id so it can + // be used to get the name of the window in the next GetProperty request. + reply, err := X.GetProperty(false, root, activeAtom.Atom, + xgb.GetPropertyTypeAny, 0, (1<<32)-1).Reply() + if err != nil { + log.Fatal(err) + } + windowId := xgb.Id(xgb.Get32(reply.Value)) + fmt.Printf("Active window id: %X\n", windowId) + + // Now get the value of _NET_WM_NAME for the active window. + // Note that this time, we simply convert the resulting byte slice, + // reply.Value, to a string. + reply, err = X.GetProperty(false, windowId, nameAtom.Atom, + xgb.GetPropertyTypeAny, 0, (1<<32)-1).Reply() + if err != nil { + log.Fatal(err) + } + fmt.Printf("Active window name: %s\n", string(reply.Value)) +} diff --git a/nexgb/examples/property.go b/nexgb/examples/property.go deleted file mode 100644 index 45144c7..0000000 --- a/nexgb/examples/property.go +++ /dev/null @@ -1,41 +0,0 @@ -package main - -import ( - "log" - - "github.com/BurntSushi/xgb" -) - -func init() { - log.SetFlags(0) -} - -func get32(buf []byte) uint32 { - v := uint32(buf[0]) - v |= uint32(buf[1]) << 8 - v |= uint32(buf[2]) << 16 - v |= uint32(buf[3]) << 24 - return v -} - -func main() { - X, err := xgb.NewConn() - if err != nil { - log.Fatal(err) - } - - root := X.DefaultScreen().Root - - aname := "_NET_ACTIVE_WINDOW" - atom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() - if err != nil { - log.Fatal(err) - } - - reply, err := X.GetProperty(false, root, atom.Atom, - xgb.GetPropertyTypeAny, 0, (1<<32)-1).Reply() - if err != nil { - log.Fatal(err) - } - log.Printf("%X", get32(reply.Value)) -} diff --git a/nexgb/examples/randr.go b/nexgb/examples/randr.go deleted file mode 100644 index 064856d..0000000 --- a/nexgb/examples/randr.go +++ /dev/null @@ -1,48 +0,0 @@ -package main - -import ( - "fmt" - "log" - - "github.com/BurntSushi/xgb" -) - -func main() { - X, _ := xgb.NewConn() - - err := X.RegisterExtension("randr") - if err != nil { - log.Fatal(err) - } - - resources, err := X.RandrGetScreenResources(X.DefaultScreen().Root).Reply() - if err != nil { - log.Fatal(err) - } - - for _, output := range resources.Outputs { - info, err := X.RandrGetOutputInfo(output, 0).Reply() - if err != nil { - log.Fatal(err) - } - - bestMode := info.Modes[0] - for _, mode := range resources.Modes { - if mode.Id == uint32(bestMode) { - fmt.Printf("Width: %d, Height: %d\n", mode.Width, mode.Height) - } - } - } - - fmt.Println("\n") - - for _, crtc := range resources.Crtcs { - info, err := X.RandrGetCrtcInfo(crtc, 0).Reply() - if err != nil { - log.Fatal(err) - } - fmt.Printf("X: %d, Y: %d, Width: %d, Height: %d\n", - info.X, info.Y, info.Width, info.Height) - } -} - diff --git a/nexgb/examples/randr/main.go b/nexgb/examples/randr/main.go new file mode 100644 index 0000000..5c56609 --- /dev/null +++ b/nexgb/examples/randr/main.go @@ -0,0 +1,84 @@ +// Example randr uses the randr protocol to get information about the active +// heads. It also listens for events that are sent when the head configuration +// changes. Since it listens to events, you'll have to manually kill this +// process when you're done (i.e., ctrl+c.) +// +// While this program is running, if you use 'xrandr' to reconfigure your +// heads, you should see event information dumped to standard out. +// +// For more information, please see the RandR protocol spec: +// http://www.x.org/releases/X11R7.6/doc/randrproto/randrproto.txt +package main + +import ( + "fmt" + "log" + + "github.com/BurntSushi/xgb" +) + +func main() { + X, _ := xgb.NewConn() + + // Every extension must be initialized before it can be used. + err := X.RandrInit() + if err != nil { + log.Fatal(err) + } + + // Gets the current screen resources. Screen resources contains a list + // of names, crtcs, outputs and modes, among other things. + resources, err := X.RandrGetScreenResources(X.DefaultScreen().Root).Reply() + if err != nil { + log.Fatal(err) + } + + // Iterate through all of the outputs and show some of their info. + for _, output := range resources.Outputs { + info, err := X.RandrGetOutputInfo(output, 0).Reply() + if err != nil { + log.Fatal(err) + } + + bestMode := info.Modes[0] + for _, mode := range resources.Modes { + if mode.Id == uint32(bestMode) { + fmt.Printf("Width: %d, Height: %d\n", mode.Width, mode.Height) + } + } + } + + fmt.Println("\n") + + // Iterate through all of the crtcs and show some of their info. + for _, crtc := range resources.Crtcs { + info, err := X.RandrGetCrtcInfo(crtc, 0).Reply() + if err != nil { + log.Fatal(err) + } + fmt.Printf("X: %d, Y: %d, Width: %d, Height: %d\n", + info.X, info.Y, info.Width, info.Height) + } + + // Tell RandR to send us events. (I think these are all of them, as of 1.3.) + err = X.RandrSelectInputChecked(X.DefaultScreen().Root, + xgb.RandrNotifyMaskScreenChange| + xgb.RandrNotifyMaskCrtcChange| + xgb.RandrNotifyMaskOutputChange| + xgb.RandrNotifyMaskOutputProperty).Check() + if err != nil { + log.Fatal(err) + } + + // Listen to events and just dump them to standard out. + // A more involved approach will have to read the 'U' field of + // RandrNotifyEvent, which is a union (really a struct) of type + // RanrNotifyDataUnion. + for { + ev, err := X.WaitForEvent() + if err != nil { + log.Fatal(err) + } + fmt.Println(ev) + } +} diff --git a/nexgb/examples/seq-nowrap.go b/nexgb/examples/seq-nowrap.go deleted file mode 100644 index 994a07b..0000000 --- a/nexgb/examples/seq-nowrap.go +++ /dev/null @@ -1,29 +0,0 @@ -package main - -import ( - "fmt" - - "github.com/BurntSushi/xgb" -) - -func main() { - X, _ := xgb.NewConn() - - for i := 1; i <= 1<<16 + 10; i++ { - X.NoOperation() - // fmt.Printf("%d. No-Op\n", i) - } - - aname := "_NET_ACTIVE_WINDOW" - - for i := 1; i <= 10; i++ { - atom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() - if err != nil { - fmt.Println(err) - } else { - fmt.Printf("%d. Sequence: %d, Atom: %d\n", - i, atom.Sequence, atom.Atom) - } - } -} - diff --git a/nexgb/examples/seq-wrap.go b/nexgb/examples/seq-wrap.go deleted file mode 100644 index b5bc834..0000000 --- a/nexgb/examples/seq-wrap.go +++ /dev/null @@ -1,24 +0,0 @@ -package main - -import ( - "fmt" - - "github.com/BurntSushi/xgb" -) - -func main() { - X, _ := xgb.NewConn() - - aname := "_NET_ACTIVE_WINDOW" - - for i := 1; i <= 1<<16 + 10; i++ { - atom, err := X.InternAtom(true, uint16(len(aname)), aname).Reply() - if err != nil { - fmt.Println(err) - } else { - fmt.Printf("%d. Sequence: %d, Atom: %d\n", - i, atom.Sequence, atom.Atom) - } - } -} - diff --git a/nexgb/examples/window.go b/nexgb/examples/window.go deleted file mode 100644 index 68fe27b..0000000 --- a/nexgb/examples/window.go +++ /dev/null @@ -1,61 +0,0 @@ -package main - -import ( - "fmt" - "log" - - "github.com/BurntSushi/xgb" -) - -func main() { - X, err := xgb.NewConn() - if err != nil { - log.Fatal(err) - } - - wid, _ := X.NewId() - X.CreateWindow(X.DefaultScreen().RootDepth, wid, X.DefaultScreen().Root, - 0, 0, 500, 500, 0, - xgb.WindowClassInputOutput, X.DefaultScreen().RootVisual, - 0, []uint32{}) - X.ChangeWindowAttributes(wid, xgb.CwEventMask | xgb.CwBackPixel, - []uint32{0xffffffff, xgb.EventMaskKeyPress | xgb.EventMaskKeyRelease}) - - err = X.MapWindowChecked(wid).Check() - if err != nil { - fmt.Printf("Checked Error for mapping window %d: %s\n", wid, err) - } else { - fmt.Printf("Map window %d successful!\n", wid) - } - - err = X.MapWindowChecked(0x1).Check() - if err != nil { - fmt.Printf("Checked Error for mapping window 0x1: %s\n", err) - } else { - fmt.Printf("Map window 0x1 successful!\n") - } - - for { - ev, xerr := X.WaitForEvent() - if ev == nil && xerr == nil { - log.Fatal("Both event and error are nil. Exiting...") - } - - if ev != nil { - fmt.Printf("Event: %s\n", ev) - } - if xerr != nil { - fmt.Printf("Error: %s\n", xerr) - } - - if xerr == nil { - geom, err := X.GetGeometry(0x1).Reply() - if err != nil { - fmt.Printf("Geom Error: %#v\n", err) - } else { - fmt.Printf("Geometry: %#v\n", geom) - } - } - } -} - diff --git a/nexgb/examples/xinerama.go b/nexgb/examples/xinerama.go deleted file mode 100644 index 7fe9984..0000000 --- a/nexgb/examples/xinerama.go +++ /dev/null @@ -1,29 +0,0 @@ -package main - -import ( - "fmt" - "log" - - "github.com/BurntSushi/xgb" -) - -func main() { - X, _ := xgb.NewConn() - - err := X.RegisterExtension("xinerama") - if err != nil { - log.Fatal(err) - } - - reply, err := X.XineramaQueryScreens().Reply() - if err != nil { - log.Fatal(err) - } - - fmt.Printf("Xinerama number: %d\n", reply.Number) - for i, screen := range reply.ScreenInfo { - fmt.Printf("%d :: X: %d, Y: %d, Width: %d, Height: %d\n", - i, screen.XOrg, screen.YOrg, screen.Width, screen.Height) - } -} - diff --git a/nexgb/examples/xinerama/main.go b/nexgb/examples/xinerama/main.go new file mode 100644 index 0000000..ec7f46a --- /dev/null +++ b/nexgb/examples/xinerama/main.go @@ -0,0 +1,39 @@ +// Example xinerama shows how to query the geometry of all active heads. +package main + +import ( + "fmt" + "log" + + "github.com/BurntSushi/xgb" +) + +func main() { + X, err := xgb.NewConn() + if err != nil { + log.Fatal(err) + } + + // Initialize the Xinerama extension. + // The appropriate 'Init' function must be run for *every* + // extension before any of its requests can be used. + err = X.XineramaInit() + if err != nil { + log.Fatal(err) + } + + // Issue a request to get the screen information. + reply, err := X.XineramaQueryScreens().Reply() + if err != nil { + log.Fatal(err) + } + + // reply.Number is the number of active heads, while reply.ScreenInfo + // is a slice of XineramaScreenInfo containing the rectangle geometry + // of each head. + fmt.Printf("Number of heads: %d\n", reply.Number) + for i, screen := range reply.ScreenInfo { + fmt.Printf("%d :: X: %d, Y: %d, Width: %d, Height: %d\n", + i, screen.XOrg, screen.YOrg, screen.Width, screen.Height) + } +} -- cgit v1.2.3-70-g09d2