Referring to How to make a dynamic stopwatch?
Timers can now be created with
timer = makeTimer[]and utilised with actions such astimer["lap"]to get the current lap time. Timers are quiescent unless asked to do something.You could extend this to handle a pause function if that's required.
How do you add that pause button?
It's not very easy to add a pause button with the approach that image_doctor took. I can't think of any way of doing it without introducing auxiliary variables and it's just not very elegant. I tried a different approach which made it easier instead. I use scheduled tasks since the comment thread in the original question indicates that this is more precise, however in this example the resolution is only one second. Resolution can be changed by changing dt, but then the visualization/the increment would also have to be adapted.
timer[] :=
With[{time = Unique["time"], dt = Unique["dt"], paused = Unique["paused"]},
time = 0; dt = 1; paused = True;
RunScheduledTask[
If[! paused, time++]
, dt];
Row[{
Column[{
Button["Start", paused = False;],
Button["Paus", paused = True],
Button["Reset", time = 0; paused = True;],
Button[Dynamic[time]]
}],
Column[{Pane[
Dynamic@
ClockGauge[{Floor[Mod[time, 60 3600]/3600], Floor[Mod[time, 3600]/60], Mod[time, 60]}],
210, Alignment -> Right]
}]
}]
]
The code looks a bit funny with the home-made localization at the beginning, I had to do this because RunScheduledTask does not work inside DynamicModule, and I did not like the fact that Mathematica marked my dynamic variables red when I used Module.
How it looks:
timer[]
When you're done you can remove the scheduled events like this:
RemoveScheduledTask[ScheduledTasks[]]
Some variables have to be added to the method of the linked question to keep track of whether the stop watch is paused and the delay accumulated by the pauses.
Here's one way to adapt the method of the linked question. It still needs RunScheduledTask[time = timer["now"], 2] to be executed.
DynamicModule[{start = AbsoluteTime[], paused = 0},
makeTimer[] :=
(start = AbsoluteTime[]; paused = 0;
Switch[#,
"now", If[paused > 0, paused - start, AbsoluteTime[] - start],
"lap", If[paused > 0, paused - start, AbsoluteTime[] - start],
"reset", start = AbsoluteTime[]; If[paused > 0, paused = start]; 0.,
"pause", (paused = AbsoluteTime[]) - start,
"restart",
If[paused > 0, start += AbsoluteTime[] - paused; paused = 0];
AbsoluteTime[] - start
] &)
];
To add a pause button, a variable has to be added to keep track of the state of the timer.
DynamicModule[{state = "Pause"},
Grid[{
{Button["Start", timer = makeTimer[]; time = 0.;
state = "Pause"]}, {Button["Lap", time = timer["lap"]]},
{Button["Reset", time = timer["reset"]]},
{Button[Dynamic@state,
If[state == "Pause",
time = timer["pause"]; state = "Restart",
time = timer["restart"]; state = "Pause"]]},
{Button[Dynamic[ClockGauge@time]]}}]
]
Adding the UpdateInterval option to Refresh can control how often the stopwatch is updated.
Here's a simpler way to make a stopwatch. Clicking on it toggles the run/pause modes. Other commands may be added to the action of the Button.
DynamicModule[{time, offset = 0, stop, update = True},
Button[Dynamic@Refresh[
ClockGauge[If[update, time = Clock[Infinity], time] - offset]],
If[update,
stop = time; update = False,
offset += Clock[Infinity] - stop; update = True]]]
