Problems with arrowkeys

[opus]

Hi,
I'm using the arrowkeys to give steering commands to a moving object. I'm using the GetAsyncKeyState API. These commands are working well.
But the commands do have a "nasty" side-effect, while using an arrow key the focus for the other control on the FORM is changing along ther direction of the arrowkey. If only the focus would be changing, the problem would be negletable, but when moving along an Option-Control the selected Option is changed, THAT is "nasty". Does anyone know a way around that. By the way, the quick solution to use other keys for the steering, is not really what I'm looking for.
Thanks

[Thanathos]

I ve been checking the api and it seems to me you have 2 options.

1) Make an Keyboard Hook to intercept specific keys (in this case the arrow keys) and delete them and then do youu own moving routine.. Well that is some pretty dificult stuff...=)

2) I Suggest you use this Code, and call ResetLastFocus every time your GetAsyncKeyState Api monitors an arrow key

Option Explicit

Dim LastInputControl as Variant

Private Sub Timer1_Timer()
Set LastInputControl=Me.ActiveControl
end sub

Private ResetLastFocus()
LastInputControl=Control.SetFocus
end sub

I havent Debuged this much but it Should Work... Please let me now how it goes

[opus]

Thank's Thanathos
I will check your code, but the answer will have to wait 'til next week, I'm on my way home. (TGIF ;-) ) I'll check it on Monday.
Greetings to the Caribic

[opus]

Hi Thanathos;
just tried your solution
I had to modify it a bit, anyhow it doesn't work. I haven't found the solution to reset the focus to the LastInputControl (I used just a fixed control) after the arrowkey is pressed.

Private Sub Timer2_Timer()
LastInputControl = Me.ActiveControl.Caption
If (GetAsyncKeyState(vbKeyLeft)) Then
    ' turn left
    TurnIndicator.Value = TurnIndicator.Value - 1
ElseIf (GetAsyncKeyState(vbKeyRight)) Then
    ' turn right
    TurnIndicator.Value = TurnIndicator.Value + 1
End If
If (GetAsyncKeyState(vbKeyUp)) And SpeedIndicator.Value > 0 Then
    ' Speed up
    SpeedIndicator.Value = SpeedIndicator.Value - 2
ElseIf (GetAsyncKeyState(vbKeyDown)) And SpeedIndicator.Value < (LfzMaxSpeed - LfzMinSpeed) Then
    ' Speed down
    SpeedIndicator.Value = SpeedIndicator.Value + 2
End If
Me.Marker2Drop.SetFocus
End Sub

Anyhow the press of an arrowkey still moves the focus around, afterwards the focus is set to the selected control (Marker2Drop).
It seems that the use of the arrowkey is directly moving the focus.
So I'm still searching

[plenderj]

I myself use the normal Form events for key presses.
When the user presses a key, I set a particular public boolean value true.

Then each time the game screen is being updated it does whatever it has to do with the key in that state, and then resets the value.

Take a look in the craft code for an example.
You'd wanna look at the Form_Key* events for the main form, and also the main game loop in there too.

[opus]

Sorry, but it doesn't do it.
I get the key_events, but that's no change. the problem is still that a press of an arrowkey not only just a key_press that can be read , it's also a command to move the focus around the active form. Thereby shifting options, if the focus is moving along such an option-field!
Damm it :-((

[plenderj]

Well focus should only be shifted if a control currently has focus.
Give the form itself focus, and also remove the TabIndex property of all the controls.

[opus]

??
Remove TabIndexProperty (whow do I do that), or only TabStop=false? The latter doesn't do it!

[plenderj]

Right neither of those will work.
Okay, if you add a picturebox to the form.

Display the game in the picturebox, and give it focus.

[opus]

OKay, I do have a picturebox in my form. If I give it the focus just before checking the Arrowkeys, the problem concerning the shifted options is gone (Thanks).
The sideeefect is that I'm now not able to make any input into textboxes, 'cause the focus will be lost. Maybe I have to stop the Timer2 during the time a textbox has the focus???? Just thinking loud.
I'll try my very best, Miss Sophie!

[plenderj]

I'd try to avoid using the textboxes if possible...

[opus]

It works, it's a bit unusual that the focus can't be held by a control, but it works as desired.
For all the controls which need an input (I have 1 textbox, and 5 comboboxes) I used the trick to disable to Timer2 while they have the focus and give it back when leaving. In my opinion it looks good. Why should I avoid textboxes?, I need some Input (I could use Comboboxes or listcontrols instead, but what's the difference?)

Most of all, THANK'S . It took a long time for me to get that solved.

[Jotaf98]

my program is not really a game, it's of a training tool for some submarine hunting tactics

Sorry, I'm just curious about that part

Submarine hunting tactics? REAL submarines, like a training program for the navy or something?

[opus]

O.K. here is a short description:
The application is made to train in the use of "Dopplerinformation" to locate a submarine. In order to make that possible the sub must produce a stable frequency which the searcher can detect on selectable locations. The change in the frequency, due to the Doppler-Phenomena, enables the searcher to locate the sub without nay other information.
In the application the searcher can select the positions where he wants to listen and also gets the frequency-information of those locations. I my special case the searcher is an aircraft (steering only for left/right and speed up/down), the sensor are socalled buoys, the frequency-informations is given on Frequency-Time indicators (Frequency horizontal, time verticaly given a picture of the actual and history information).
There is no fancy visualisation, since no real pictures of aircraft nor submarines are needed. So no real "game", the clou only comes to those who learned such tactics and who wanted to keep trained in the use of them.
It's not used by the "navy" (yet??), I'm working on it.

[plenderj]

Do you have to kill us now ?

[Jotaf98]

Opus, that seems really cool, but I don't think the navy will make it official unless you know some people there, or you're in the navy

[opus]

Jotaf98, something makes me think you're a student ;-)

[opus]

Thanks plenderj,
the GetTickcount is controlling it now, using a setting of 500 (millisecs), the normal click_events are not blocked and the steering comands work as desired. However, there is a small problem, if I close the application no using the X in the right hand corner I get a runtime-error 5 at the line where the focus is set to a picturebox. This is not happening when closing normally via an end command.?????

[plenderj]

Well it could be due to the fact that the loop is still runnning even though the form is unloading.

So if you do something like this :

Do While DoLoop
    DoEvents
    If (GetTickCount() - LastTick) >= 500 Then
        LastTick = GetTickCount()
        'your code here
    End If 
Loop

Then when you're going to be unloading the form for whatever reason, set DoLoop = False

[opus]

Okay, but whre do I have to put code that is supposed to be used in case of the click on the "X" of the MainForm. That "X" just closes the form. Or is there an event Unload?

[plenderj]

Option Explicit
Private closedByApp As Boolean
 
 
Private Sub Command1_Click()
    closedByApp = True
    Unload Me
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
    If Not closedByApp Then MsgBox "Someone clicked the x !"
End Sub

[Jotaf98]

Opus: did you see my profile or something? It's not hard to figure that out, I'm 15

As to your problem, it's easy, I think they already gave you what you need... a better way would be to have "End" in the Form_Unload event. That would be even better (and simplier) than what they're suggesting

[plenderj]

Originally posted by Jotaf98
Opus: did you see my profile or something? It's not hard to figure that out, I'm 15

As to your problem, it's easy, I think they already gave you what you need... a better way would be to have "End" in the Form_Unload event. That would be even better (and simplier) than what they're suggesting

"they" jotaf ?
Whats that supposed to mean

[Jotaf98]

Hum, maybe you could trap key presses another way - here's how

Btw, this demo is set up to work with keys F1-12, but you can easily use other keys, don't worry

[opus]

Great Jotaf98, the link brought an attachment.php and not a *.zip file!

Anyway, the problewm is solved, and I was stupid. No need to use a loop the set the focus to the picturebox, I'm setting the focus to the picbox now each time a click on an other control happens, that way the arrowkeys have no sideeffects and the change to another window is also not affected. I think we can close this one now.
Thanks to both of you!

[plenderj]

No problem, just leave the cheque on the way out.

[Jotaf98]

Yeah and the car's keys too

Weird, the download works for me. Are you sure it's only this one that doesn't work? Try downloading other attachments in other posts. Also if you're using a downloader like FlashGet, GetRight or Go!Zilla, it won't work unless you have the latest version. Use IE or NS's downloader instead, after all the file is only 5 or 6 kb