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WPF- how to create a kind of a screensaver (with timer)

I do not know how to solve this problem:
I want in my WPF Application something like a screensaver which pops up (let's say after 20 seconds) if you do not interact with the program. I tried researching, but I did not find anything and I do not know how to start. Does anyone have any tips for me?

You can for example start DispacherTimer and reset it if person move mouse or click something. In event check is time's up start new window/popup/dialog modal with screensaver, if person move mouse or click in screensaver close it and back to previous window.
Something about DispacherTimer you can find here:
WPF Timer Like C# Timer
or here https://msdn.microsoft.com/en-gb/library/system.windows.threading.dispatchertimer%28v=vs.90%29.aspx

You can do something like this then all you have to do is just set a timmer in the app.cs that resets.
private DispatcherTimer _timer;
protected override void OnStartup(StartupEventArgs e)
{
_timer = new DispatcherTimer();
_timer.Tick += Timer_Tick;
_timer.Interval = new TimeSpan(0,0,0,20,0);
_timer.Start();
EventManager.RegisterClassHandler(typeof(Window),Window.MouseMoveEvent, new RoutedEventHandler(Reset_Timer));
EventManager.RegisterClassHandler(typeof(Window), Window.MouseDownEvent, new RoutedEventHandler(Reset_Timer));
EventManager.RegisterClassHandler(typeof(Window), Window.KeyDownEvent, new RoutedEventHandler(Reset_Timer));
}
private void Timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("Ticked");
}
private void Reset_Timer(object sender, EventArgs e)
{
_timer.Interval = new TimeSpan(0,0,0,20,0);
}
This will reset the timer every time you move your mouse click your mouse or push any key in the window.

c# timer preventing button click

I am currently trying to create a hover effect on a custom control, where a panel (panel1) shows up after the mouse enters the control.
I have a timer that starts when the mouseleave event is raised, the interval is 250ms, and there is an onTick event that changes the visibility of the panel1 to false.
This all works. However, the buttons on panel1 do not always respond when clicked.
Here is the pertinent code - I will supply anything else that is required if I'm missing some information.
private void MagicCardViewer_MouseLeave(object sender, EventArgs e)
{
timer1.Start();
timer1.Interval = 250;
timer1.Tick += new EventHandler(timer1_TickOff);
timer1.Tick -= timer1_TickOn;
}
private void MagicCardViewer_MouseEnter(object sender, EventArgs e)
{
showPanel1();
}
public void showPanel1()
{
//show necessary controls
buttonDiscard.Show();
//show panel1
panel1.Visible = true;
ActiveControl = panel1;
}
public void hidePanel1()
{
panel1.Visible = false;
//hide controls
}
# region button events
private void buttonChoose_Click(object sender, EventArgs e)
{
Chosen = !Chosen;
if (Chosen)
{
callCardChosen();
}
}
private void buttonTap_Click(object sender, EventArgs e)
{
cards[0].ChangeTap();
DrawCardTap();
onCardChanged();
}
private void buttonActivate_Click(object sender, EventArgs e)
{
cards[0].TryActivate(0);
}
private void buttonDiscard_Click(object sender, EventArgs e)
{
cards[0].onDiscard();
}
# endregion
I think that is everything, but there is a lot of code to select from.
breakpoints don't trigger, the button flashes but nothing happens. If the timer interval is set very long, it works fine, but the point is for the button to vanish quickly once the mouse leaves the control. If the mouse is on the buttons, then the form reports it as having left the control.
To sum up - the buttons are not always processing when I click on them.

If you have the timer ticking every 250ms that could prevent the event on the mouse click.
I would check that you stop the timer after the tick if you no longer need it, and restart as I think you are doing when the user leaves the control or enter it again.
This could be why it works when you set a longer time interval.

how to increment the variable correctly?

when I start the timer ..timel is incremented normally ..but as soon as I stop the timer i.e. call the click_TimerStop function and start the timer again...the timel variable is incremented by timel+=2..and when I repeat the process ..it is increased by timel+=3..and it goes on and on ...how do I correct this ?..
DispatcherTimer clktimer = new DispatcherTimer();
private void click_TimerStart(object sender, RoutedEventArgs e)
{
clktimer.Start();
clktimer.Interval =new TimeSpan(0,0,1);
clktimer.Tick +=clktimer_tick;
}
private int timel = 0;
private void clktimer_tick(object sender, object e)
{
timel++;
timerSecond.Text = timel.ToString();
}
private void click_TimerStop(object sender, RoutedEventArgs e)
{
clktimer.Stop();
}

add
clktimer.Tick -=clktimer_tick;
before
clktimer.Tick +=clktimer_tick;
you'll unsubscribe and subscribe to event, so only one handler will be active at a time
and It's better to call start() after you set all settings to timer

It's because you're continually adding the clktimer_tick event handler each time you start the timer. Initialize your timer somewhere where it will only be called once and not every time you start, because there's no need to keep setting the same settings each time.

Raise event after 30 seconds of no user interaction

I'm programming a WPF application, and I'd like to raise an event if the user has not interacted with the program for 30 seconds. That is to say, no keyboard or/and mouse events.
The reason I want do do this is because I want to bring attention to the screen if a variable alertstate has been set to true.
I'm thinking of using something along the lines of BackgroundWorker but I really don't know how I can get the time a user has not interacted with the program. Can someone point me in the right direction?
I guess this question basically comes down to checking if a user has interacted with the screen. How do I do this?

One way you could do this is to use GetLastInputInfo. This information will give you the time elapsed (in ticks) since last user interaction on mouse/keyboard.
You can have information here :
http://www.pinvoke.net/default.aspx/user32.GetLastInputInfo
So have a timer which checks for the last time an interaction went on. If you need accuracy, you can either check each 5 second for example OR you can, when you see that idle is ongoing for y seconds (y<30), setup a one-time timer that will check for idle time after (30-y) seconds.

You need to record the last time the user moved the mouse or pressed a key and then check if that time is greater than your threshold.
So you need to add mouse move, mouse click and keyboard handlers to your application (this is Silverlight code so you might have to change namespaces etc.):
private void AttachEvents()
{
Application.Current.RootVisual.MouseMove += new MouseEventHandler(RootVisual_MouseMove);
Application.Current.RootVisual.KeyDown += new KeyEventHandler(RootVisual_KeyDown);
Application.Current.RootVisual.AddHandler(UIElement.MouseLeftButtonDownEvent, (MouseButtonEventHandler)RootVisual_MouseButtonDown, true);
Application.Current.RootVisual.AddHandler(UIElement.MouseRightButtonDownEvent, (MouseButtonEventHandler)RootVisual_MouseButtonDown, true);
}
Then in the handlers have code like this for the mouse move:
private void RootVisual_MouseMove(object sender, MouseEventArgs e)
{
timeOfLastActivity = DateTime.Now;
}
and a similar one for the KeyDown event handler.
You will have to set off a timer:
idleTimer = new DispatcherTimer();
idleTimer.Interval = TimeSpan.FromSeconds(1);
idleTimer.Tick += new EventHandler(idleTimer_Tick);
// Initialise last activity time
timeOfLastActivity = DateTime.Now;
Then in the tick event handler have something like this:
private void idleTimer_Tick(object sender, EventArgs e)
{
if (DateTime.Now > timeOfLastActivity.AddSeconds(30))
{
// Do your stuff
}
}

Use ComponentDispatcher.ThreadIdle and DispatcherTimer to achieve this.
DispatcherTimer timer;
public Window1()
{
InitializeComponent();
ComponentDispatcher.ThreadIdle += new EventHandler(ComponentDispatcher_ThreadIdle);
timer = new DispatcherTimer();
timer.Interval = TimeSpan.FromSeconds(30);
timer.Tick += new EventHandler(timer_Tick);
}
void timer_Tick(object sender, EventArgs e)
{
//Do your action here
timer.Stop();
}
void ComponentDispatcher_ThreadIdle(object sender, EventArgs e)
{
timer.Start();
}

Using a timer to display text for 3 seconds?

Is it possible to use a timer to show text in a label for like 3 sec ?
F.E. When you saved something and it was successful, you'd get a text message "success!" for 3 second and then return to the original page.
Anyone knows how to do this using a label or a messagebox ?

Yes, it s possible...
You may start the timer at where you set the text of the label to "succcess" and set it to tick after 3 seconds and then at the timer_ticks event, you may redirect to the page you want.
Edit: the code to start the timer - This is a simple windows form having one button and one label
public partial class Form1 : Form
{
//Create the timer
System.Windows.Forms.Timer myTimer = new System.Windows.Forms.Timer();
public Form1()
{
InitializeComponent();
//Set the timer tick event
myTimer.Tick += new System.EventHandler(myTimer_Tick);
}
private void button1_Click(object sender, EventArgs e)
{
//Set the timer tick interval time in milliseconds
myTimer.Interval = 1000;
//Start timer
myTimer.Start();
}
//Timer tick event handler
private void myTimer_Tick(object sender, System.EventArgs e)
{
this.label1.Text = "Successful";
//Stop the timer - if required
myTimer.Stop();
}
}

sure, that is possible. your going to want to do it with javascript/jquery on the client side to avoid a page refresh, i am thinking. here is a link to how to run javascript on a timer.