invalidation

问题 I have searched many times on the internet but could not find the answer to this question. I know how to pause and resume NSTimers by using the invalidate functions - timer.invalidate. and I know how to resume them. But I have a SpriteKit game. When I pause my game, I stop everything and the timers. I know that I can stop them using .invalidate but when I invalidate them: For example lets say I have a 5 second timer that runs continously that spawns one block. When the timer reaches second 3

问题 I have a code just like this: std::vector<int> v1 = { 1, 2, 3, 4 }; std::vector<int> v2 = { 7, 8, 9, 10 }; std::vector<int>::iterator it = std::next(v1.begin()); v1 = v2; int test = *it; std::cout << test; The above code will throw an error: iterator not dereferencable. However, if I replace vector with list as follows: std::list<int> v1 = { 1, 2, 3, 4 }; std::list<int> v2 = { 7, 8, 9, 10 }; std::list<int>::iterator it = std::next(v1.begin()); v1 = v2; int test = *it; std::cout << test; The

问题 I have a FrameLayout that contains several ImageView. On the main activity, I record the touch events in order to move my FrameLayout and the images inside with the finger (drag). For doing so, I am calling canvas.translate(x,y) inside the onDraw of the framelayout which is called by a invalidate() in the activity touch event handler. Everything works like a charm except that after the translate, I am not able to click on my ImageView. In fact, the click listener of each image is still at the

问题 I'm trying to build shinyapp to make a very simple quizz. I have a data.frame with 10 questions, and the user clicks to answer either 0 or 1. It worked until I tried to implement a timer / countdown so that the next question appears automatically after 5 seconds, using an invalidateLater() call. The current question number is stored in a reactiveValues() object, variable i When I add my observe function, the app stopped working and did not display the question. My code is here: init = data

问题 I have 10-50 files upload at the same time. Lambda triggers an event for every updated file (if file size changed). So instead of invalidating one by one 50x I'd like to run the wildcard “*” character once at the end of the upload. Anyone can shed some light on how to accomplish that? Thanks! 回答1: If I understood your question correctly, your lambda function knows whether CloudFront should invalidate or not but does not know when should that happen exactly. In that case, you could return a

问题 I have a class with the getters/setters for interacting with an underlying device driver. The getter reads data from device and the setter writes data to device. I would add a FX property to this class in order to bind to a GUI controls. I build the property by using JavaBeanPropertyBuilder and it's works. But the property value can be changed not only on GUI side but also on a device side, so I need update the properties by a timer and I want force invalidate the properties in order to

问题 I have the following code that takes a string and erases non alphabet characters void removeNonAlpha(string& str){ for (string::iterator it = str.begin(); it < str.end(); it++){ if (!(isUpperCaseLetter(*it) || isLowerCaseLetter(*it) || str == ' ')) str.erase(it--); } } I showed this to my professor and he told me that doing this is risky because it may invalidate the iterator that I'm using. However, I thought that erase will only invalidate iterators after the point of the erase, and I made

问题 I am trying to move a drawn graphics item, I can draw them just fine. but when I try to move it, it just draws another item over the original. I have tried Invalidate, and pictureBox1.Invalidate. still no luck just prints both items to the pictureBox. Thanks for any suggestions. private void button1_Click(object sender, EventArgs e) { count++; button1.Text = "Move"; if (count == 1) { car(); } else if (count == 2) { car1(); } } public void car() { Invalidate(); g = pictureBox1.CreateGraphics()

问题 How can I get the current Android view when it displays data that has been updated, and force it to be redrawn? I worked through Android's Notepad tutorial and completed lesson three without any problems — the solution is provided, after all — but I'm stuck on my first non-trivial modification. I added a new button to the menu, next to the Add note button. When pressed, that button adds a letter to the title of each note in the system. However, the new titles don't show up in the list of

问题 Here's my issue, I have contact form 7 for wordpress installed and during the wpcf7_before_send_mail I make a call to an API, I need to invalidate the form if the API returns an error then I need to invalidate the request and return the error passed back from the API call. I set a flag to false on API failure and the error message is also stored but my form is going through as success despite the failure I induce. add_action("wpcf7_before_send_mail", "wpcf7_send_contact_builder"); function