1X11::Protocol::ChooseWiUnsdeorw(C3o)ntributed Perl DocumXe1n1t:a:tPiroontocol::ChooseWindow(3)
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6 X11::Protocol::ChooseWindow -- user click to choose window
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9 use X11::Protocol::ChooseWindow;
10 my $client_window = X11::Protocol::ChooseWindow->choose (X => $X);
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13 This spot of code lets the user click on a toplevel window to choose
14 it, in a similar style to the "xwininfo" or "xkill" programs.
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16 Implementation
17 The choose is implemented in a similar way to the "xwininfo" etc
18 programs. It consists of "GrabPointer()" on the root window, wait for
19 a "ButtonPress" and "ButtonRelease" from the user, get the frame window
20 from the "ButtonPress" event, then the client window under there from
21 "frame_window_to_client()" of "X11::Protocol::WM".
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23 "KeyPress" events are not used and they go to the focus window in the
24 usual way. This can be good in a command line program since it lets
25 the user press "^C" ("SIGINT") in an "xterm" or similar. Perhaps in
26 the future there could be an option to watch for "Esc" to cancel or
27 some such.
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29 A virtual root per "root_to_virtual_root()" in "X11::Protocol::WM" is
30 used if present. This helps "ChooseWindow" work with "amiwm" and
31 similar virtual root window managers.
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34 The following "choose()" is in class method style with the intention of
35 perhaps in the future having objects of type
36 "X11::Protocol::ChooseWindow" holding state and advanced by events
37 supplied by an external main loop.
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39 Choosing
40 "$window = X11::Protocol::ChooseWindow->choose (key=>value,...)"
41 Read a user button press to choose a toplevel window. The
42 key/value options are as follows,
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44 X => X11::Protocol object
45 display => string ":0:0" etc
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47 screen => integer, eg. 0
48 root => XID of root window
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50 time => integer server timestamp
51 event => hashref of event initiating the choose
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53 cursor => XID of cursor
54 cursor_glyph => integer glyph for cursor font
55 cursor_name => string name from cursor font
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57 "X" or "display" gives the server, or the default is to open the
58 "DISPLAY" environment variable. "X" for an "X11::Protocol" object
59 is usual, but sometimes it can make sense to open a new connection
60 just to choose.
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62 "root" or "screen" gives the root window to choose on, or the
63 default is the current screen of $X, which in turn defaults to the
64 screen part of the display name. If there's a window manager
65 virtual root then that's automatically used as necessary.
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67 "time" or the time field in "event" is a server timestamp for the
68 "GrabPointer()". This guards against stealing a grab from another
69 client if badly lagged. Omitted or "undef" means "CurrentTime".
70 In a command line program there might be no initiating event,
71 making "CurrentTime" all that's possible.
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73 "cursor" etc is the mouse pointer cursor to show during the choose,
74 as a visual indication to the user. The default is a "crosshair".
75 "cursor_name" or "cursor_glyph" are from the usual cursor font.
76 See X11::CursorFont for available names. For example perhaps the
77 "exchange" cursor to choose a window for some sort of swap or flip,
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79 $window = X11::Protocol::ChooseWindow->choose
80 (X => $X,
81 cursor_name => "exchange");
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83 A "cursor" XID can be created by any client as usual. Don't forget
84 to flush if creating a cursor from one connection, so it's ready
85 for use from another.
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88 X11::Protocol, X11::Protocol::WM, X11::CursorFont
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90 xwininfo(1), xkill(1), and their dsimple.c "Select_Window()" code
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92 "Inter-Client Communication Conventions Manual" section "WM_STATE
93 Property" for notes on using "WM_STATE" to identify client windows.
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96 <http://user42.tuxfamily.org/x11-protocol-other/index.html>
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99 Copyright 2010, 2011, 2012, 2013, 2014, 2016, 2017, 2019 Kevin Ryde
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101 X11-Protocol-Other is free software; you can redistribute it and/or
102 modify it under the terms of the GNU General Public License as
103 published by the Free Software Foundation; either version 3, or (at
104 your option) any later version.
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106 X11-Protocol-Other is distributed in the hope that it will be useful,
107 but WITHOUT ANY WARRANTY; without even the implied warranty of
108 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
109 General Public License for more details.
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111 You should have received a copy of the GNU General Public License along
112 with X11-Protocol-Other. If not, see <http://www.gnu.org/licenses/>.
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116perl v5.30.1 2020-01-30 X11::Protocol::ChooseWindow(3)