I following a guide to display seconds in XNA, but was now wondering how to make the seconds count-up ONLY when I press Spacebar. So, when I start the game, the seconds don't start automatically, but only when I press the spacebar.
Is it possible to do this?
This will do what you ask. All I did was add a timerEnabled variable and set to true in the updated method if the SpaceBar was pressed. I also added a line that won't start the timer until timerEnabled is set to true.
public class Game1 : Microsoft.Xna.Framework.Game
{
//Put this variable at the top with the others.
bool timerEnabled;
protected override void Update( GameTime gameTime )
{
if ( Keyboard.GetState().KeyDown( Key.Space ) ) timerEnabled = true;
if (timerEnabled) _timer += gameTime.ElapsedGameTime.TotalMilliseconds;
base.Update( gameTime );
}
}
KeyboardState state = Keyboard.GetState()
if(state.KeyDown(Key.Space))
_timer += ......
Something like that should help you on start.
Basically, check if key is down and if it is, add more time to _timer.
Related
I am trying to develop an app using Xamarin.Forms. At a certain point I am trying to have multiple switches that are grouped. This is to say that when one switch is toggled, every other switch needs to be untoggled and, at the same time, there needs to be at least one switch always toggled. This is to say that tapping on a switch that is already toggled should not change anything.T
Now my problem is that Xamarin.forms Toggled event for switches can be fired from the UI, but is also fired programmatically. I thought I had found a way around this problem, but still by doing:
-If the switch was turned on, turn off all others and do application stuff.
-else if a switch was turned off, check if there are any others that are on. If not, turn the switch back on. If yes, do nothing.
A sample code for two switches could be:
private void OnFirstToggled(object sender, EventArgs args)
{
if(FirstSwitch.isToggled)
{
//Application stuff.
SecondSwitch.isToggled = false;
}
else if (!SecondSwitch.isToggled)
{
FirstSwitch.isToggled = true;
}
}
private void OnSecondToggled(object sender, EventArgs args)
{
if(SecondSwitch.isToggled)
{
//Application stuff.
FirstSwitch.isToggled = false;
}
else if (!FirstSwitch.isToggled)
{
SecondSwitch.isToggled = true;
}
}
This solution results in an infinite loop when an already toggled switch is tapped. In fact, the isToggled property of the switch alternates between true and false infinitely. However when debugging the other event never seems to be fired (or at least my debugger does not see it). This is why I don't understand where the isToggled property is changed after that first tap.
I know this is probably a very simple issue, but I cannot seem to find the solution somewhere online. Can anyone see the problem or recommend a better, common way to implement this?
I write a simple solution to you to always keep one Switch open from a Switch group.
Let's first add three switch for test, make sure these Switch will fire the same event of Toggled:
<StackLayout>
<!-- Place new controls here -->
<Switch Toggled="Switch_Toggled" x:Name="FirstSwitch"/>
<Switch Toggled="Switch_Toggled" x:Name="SecondSwitch"/>
<Switch Toggled="Switch_Toggled" x:Name="ThirdSwitch"/>
</StackLayout>
In the code behind, I add those Switches into a list, and loop them in Switch_Toggled event to open/close the Switches:
public partial class MainPage : ContentPage
{
List<Switch> switchList;// To store all your Switches
bool isLooping; //To make sure the Switch_Toggled metod not fired a second time during one toogle event
public MainPage()
{
InitializeComponent();
switchList = new List<Switch>();
switchList.Add(FirstSwitch);
switchList.Add(SecondSwitch);
switchList.Add(ThirdSwitch);
isLooping = false;
}
private void Switch_Toggled(object sender, ToggledEventArgs e)
{
//To make sure the Switch_Toggled metod not fired a second time during one toogle event
if (isLooping == true)
{
return;
}
isLooping = true;
Switch clickSwitch = sender as Switch;
clickSwitch.IsToggled = true;
foreach (var tempSwitch in switchList)
{
if (tempSwitch != clickSwitch)
{
if (tempSwitch.IsToggled == true)
{
tempSwitch.IsToggled = false;
}
}
}
isLooping = false;
}
}
You can try this solution and feel free to ask me any question if you don't understand.
Your problem are the two else blocks. Take in account that you're toggling it on anyway.
I'm learning to develop windows phone application. I started with a browser based app by following this tutorial - http://blogs.msdn.com/b/jaimer/archive/2011/02/04/back-button-press-when-using-webbrowser-control-in-wp7.aspx. I'm experimenting with http://m.facebook.com I can correctly use back button to go to the previous page and all that stuff but I'm not able to implement exit on double tap of back button.
I have seen many browsers app which exit after double tapping the back button. for example - Flipkart - http://www.windowsphone.com/en-us/store/app/flipkart/84fc03ea-210d-4e3e-88e0-de502a2434c5
There is no double tab event for back button. How can we achieve this?
You can create a global long that represents the last time the user pressed the back button.
Every time the back button is pressed, you can make your program subtract the number of elapsed ticks. If it has passed a short amount of ticks, you can make your program exit. If not, set the last tick variable once more.
You can get the current tick that represents the current time with System.DateTime.Ticks.
Simple code sample:
long LastExitAttemptTick = DateTime.Ticks;
private void BackButtonPressHandler(...)
{
long thisTick = DateTime.Ticks;
if (LastExitAttemptTick - thisTick < [specified amount])
throw new Exception("Exit Exception"); //You can use XNA, but this is a quick and dirty way of exiting
else
LastExitAttemptTick = DateTime.Ticks;
}
You can use a value of 10,000,000 ticks (1 second). MSDN says 10,000 ticks per millisecond, so 10,000 * 1000 = 10,000,000.
EDIT: Or as you said, you can also use DateTime.Now and use the seconds value instead. Either way works.
well this kind of logic could work for you
make a global variable
int Count=0
protected ovverride void OnBackKeyPress(CancelEventArgs e)
{
if(Count==0)
{
e.Canel=true;
Count++;
}
else if(Count==1)
{
Count=0;
//code for exiting
//may be App.Current.Terminate(); in wp8
//or in wp7
//if (NavigationService.CanGoBack)
//{
// while (NavigationService.RemoveBackEntry() != null)
// {
// NavigationService.RemoveBackEntry();
// }
//}
}
}
Hope this helps
To close the application on double click, you can use DispatcherTimer task to check whether a two clicks are within one second, if yes close the application else start timer and again check. The snippet for that as follows:
make a DispatcherTimer object as a class field like,
DispatcherTimer dt = new DispatcherTimer();
In your class's constructor specify the interval you want to check for double tap and also add event handler to perform some action when specified time has elapsed. You can do in a class's constructor,
dt.Interval = TimeSpan.FromSeconds(1.0);
dt.Tick += delegate(object s, EventArgs e)
{
dt.Stop();
};
Here what we're doing is we're specifying timespan of 1 second to check whether double tap occurs within that second. Tick event is for what we want to do when timer completes its 1 second. We're simply going to stop the timer.
Now navigate to back key event handler and here is my code to check double tap:
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
e.Cancel = true;
if (!dt.IsEnabled)
dt.Start();
else
new Microsoft.Xna.Framework.Game().Exit();
}
When for the first tap, timer is not started, it will go to if condition and will start the timer. If second tap occurs after 1 second, then the Tick event we wrote in constructor will fire and according to logic written there, the timer will stop.
Now assume the double tap occurs consequently within 1 second. For the 1st tap as usual it will start the timer, if immediately user presses back button again, then in its handler, it will check whether timer is running. As timer has not completed its 1 second interval, else condition will fired up and the application will close.
I used XNA library / shortcut to force close the application. To work with new Microsoft.Xna.Framework.Game().Exit(); method you should add a microsoft.xna.framework.game.dll in a reference.
Make TimeSpan interval as required.
Hope this helps. Thanks.
EDIT:
Sometimes XNA is not installed on windows 8. Here is a solution for that, so that you add above mentioned assembly reference in you project.
http://blogs.msdn.com/b/astebner/archive/2012/02/29/10274694.aspx
You have to download update which is around around 23MB.
To save time here's a Dropbox link to above assembly reference:
https://db.tt/RYTwv7cS
Yes there is no Double Tap event for back button. You have to write your own logic to exit application on Double Tap on device back key tap twice. Here is the solution this may be help you.
Create a Global variable and initialize with zero
Int TapCount =0;
Now Override OnBackKeyPress event with your own logic.
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
TapCount++;
if(TapCount==2)
{
if( windows phone 8 )
{
Application.Current.Terminate();
}
else
{
if (NavigationService.CanGoBack)
{
while (NavigationService.RemoveBackEntry() != null)
{
NavigationService.RemoveBackEntry();
}
}
}
}
else
e.Canel=true;
base.OnBackKeyPress(e);
}
It's very simple. I've implemented it like this:
First declare global variable:
int count;
Now initialize its value in OnNavigatedTo(NavigationEventArgs e) method:
count = 0;
Now at last add the below code to your cs file:
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
count++;
e.Cancel = true;
if(count == 2)
{ e.Cancel = false; base.OnBackKeyPress(e); }
}
i have 2 tframes, and an add button. I am trying to add one tframe onto the other when the button is press. but for w.e reason my code can't seem to work. it's not adding the frame like it's suppose to. there is no errors or running, it compiles and runs, but when i press the button it does nothing. i got it to work when i added a tframe to a scrollbox, and all i did was change the location for the tframe to be added.
code for TFrame2
void __fastcall TFrame2::AddFrame()
{
int temp = 0;
TFrame1* NewFrame1 = new TFrame1(this);
NewFrame1 ->Parent=this;
TComponentEnumerator * ParentEnum = GetEnumerator();
while(ParentEnum->MoveNext())
{
temp++;
}
NewFrame1 ->SetIndex(temp);
NewFrame1 ->Name = "Frame" + IntToStr(temp);
NewFrame1 ->Top = ( NewFrame1 ->Height ) * (temp);
}
this is the code i use for TFrame1 itself
void __fastcall TFrame1 ::SetIndex(int temp)
{
this->temp= temp;
}
int __fastcall TFrame1 ::GetIndex()
{
return this->temp;
}
a lil bg info: the reason i have to add tframe to another tframe, is so i can add a group of components onto another group of components, i didn't know any other way to do it. later on i add tframe2 onto the main form.
Given the code you have shown, the only thing that could be going wrong is if you are setting the child frame's Top property to a value that exceeds the Height property of its parent frame so that you would not see the child frame appear onscreen even though it does exist in memory.
I'm making a simple matching game and would like a count down timer. Is there a way to set off an event every dt? I found some code using threads, but seems a lot more complicated for what I need.
Something like this should work:
TimerTask countdown = new TimerTask() {
public void run() {
synchronized(UiApplication.getEventLock()) {
//do the stuff to the UI, ie change the counter
}
}
};
Timer timer = new Timer();
timer.scheduleAtFixedRate(countdown, 0, dt);
I didn't test this, so I may have a typo in there, but this is the basic idea. Take a look at the TimerTask and Timer documentation for more info.
I've been developing with QT for around a week now and am pleased to say that I'm picking it up really fast. I'm an intermediate C++ programmer but picking up some parts of QT is proving to be challenging. I need to process key press events from the QPlainTextEdit when the user presses enter and I presume that the solution will involve sub classing the widget. Can any of you smart guys give me a potential implementable solution?
To really understand Qt and event handling there are two key areas of the documentation you should read. The first is the overview on The Event System and the second is a very important bit which is a cleverly hidden link on that page for QCoreApplication::notify. They should really move that to the main page of the Event System documentation as it really makes things quite clear (to me at least).
If you only need to handle some messages sent to the control - like the key-presses - there is no need to subclass it. You can alternatively use the event filtering mechanism. Here is a simple example:
Provide virtual eventFilter method in one of your QObject-based classes (e.g. the window form class).
bool MyWindow::eventFilter(QObject *watched, QEvent *event)
{
if(watched == ui->myTargetControl)
{
if(event->type() == QKeyEvent::KeyPress)
{
QKeyEvent * ke = static_cast<QKeyEvent*>(event);
if(ke->key() == Qt::Key_Return || ke->key() == Qt::Key_Enter)
{
// [...]
return true; // do not process this event further
}
}
return false; // process this event further
}
else
{
// pass the event on to the parent class
return QMainWindow::eventFilter(watched, event);
}
}
Install your class as the event filter for the target control. Form constructor is usually a good place for this code. In the following snippet this refers to the instance of class in which you implemented the eventFilter method.
ui->myTargetControl->installEventFilter(this);
i would try subclassing QPlainTextEdit and reimplementing QWidget::keyPressEvent:
void YourTextEdit::keyPressEvent ( QKeyEvent * event )
{
if( event->key() == Qt::Key_Return )
{
// optional: if the QPlainTextEdit should do its normal action
// even when the return button is pressed, uncomment the following line
// QPlainTextEdit::keyPressEvent( event )
/* do your stuff here */
event->accept();
}
else
QPlainTextEdit::keyPressEvent( event )
}
please try :
if (event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter){
//do something
}
in your keyPressEvent() function.