Tutorial by Examples: u

When a user press F1 on a control or click on Help button of form (?) and then clicks on a control the HelpRequested event will be raised. You can handle this event to provide custom action when user requests help for controls or form. The HelpRequested supports bubble up mechanism. It fires for y...

You can use Help class in code, to provide these kinds of help: Show a help pop-up for a control Open a CHM file based on context (Show table of content, Show a keyword or index, show a topic) Navigate to a URL using default browser Show Help pop-up window You can use Help.ShowPopup to disp...

You can show a Help Button at title-bar of a Form. To do so, you should: Set HelpButton property of form to true. Set MinimizeBox and MaximizeBox to false. Then a help button will appear on title-bar of Form: Also when you click on Help button, the cursor will be changed to a ? cursor: ...

If you have a Form with MinimizeBox and MaximizeBox set to true, then you can not show Help button on title-bar of Form and will lose the feature of click on help button to convert it to help cursor to be able to click on controls to show help. You can make a menu item on MenuStrip act like standar...

You can detect when a user Clicked on a HelpButton on title-bar of form by handling HelpButtonClicked. You can let the event continue or cancel it by setting Cancel property of its event args to true. private void Form1_HelpButtonClicked(object sender, CancelEventArgs e) { e.Cancel = true; ...

SELECT product, SUM(quantity) AS "Total quantity" FROM order_details GROUP BY product;

Assume a table of employees in which each row is an employee who has a name, a department, and a salary. SELECT department, MIN(salary) AS "Lowest salary" FROM employees GROUP BY department; This would tell you which department contains the employee with the lowest salary, and what t...

You can create a set of radio buttons used to select an item from a list. It's possible to change the settings : selected : The initially selected value (character(0) for no selection) inline : horizontal or vertical width It is also possible to add HTML. library(shiny) ui <- fluidPa...

Below is a recursive code to reverse a string /** * Just a snippet to explain the idea of recursion * **/ public class Reverse { public static void main (String args[]) { String string = "hello world"; System.out.println(reverse(string)); //prints dlrow oll...

SELECT * FROM Cars WHERE status IN ( 'Waiting', 'Working' ) This is semantically equivalent to SELECT * FROM Cars WHERE ( status = 'Waiting' OR status = 'Working' ) i.e. value IN ( <value list> ) is a shorthand for disjunction (logical OR).

A pointer (resp. reference) to an object type can be converted to a pointer (resp. reference) to any other object type using reinterpret_cast. This does not call any constructors or conversion functions. int x = 42; char* p = static_cast<char*>(&x); // error: static_cast cannot perf...

Custom Fonts for UI components from storyboard can be easily achieved with User Defined Runtime Attributes in storyboard and Categories. The advantages are like, No need to define outlets for the ui element No need to set font for elements programatically. Steps to follow Font File: A...

Before we download and install Composer, we need to make sure our server has all dependencies installed. First, update the package manager cache by running: sudo apt-get update Now, let's install the dependencies. We'll need curl in order to download Composer and php5-cli for installing and run...

First make utility class or use this method in class needed public class UIUtils { public static BitmapImageViewTarget getRoundedImageTarget(@NonNull final Context context, @NonNull final ImageView imageView, final float radius) { retur...

echo %var% This code will echo the value of var If setLocal EnableDelayedExpansion is used, the following will echo the value of var (the standard expression %var% will not work in that context). echo !var! In batch files, variables can be used in any context, including as parts of commands ...

Warning: The functions atoi, atol, atoll and atof are inherently unsafe, because: If the value of the result cannot be represented, the behavior is undefined. (7.20.1p1) #include <stdio.h> #include <stdlib.h> int main(int argc, char** argv) { int val; if (argc < 2) ...

The contents of files and network messages may represent encoded characters. They often need to be converted to unicode for proper display. In Python 2, you may need to convert str data to Unicode characters. The default ('', "", etc.) is an ASCII string, with any values outside of ASCII ...

UI testing tools Two main tools that are nowadays mostly used for UI testing are Appium and Espresso. AppiumEspressoblackbox testwhite/gray box testingwhat you see is what you can testcan change inner workings of the app and prepare it for testing, e.g. save some data to database or sharedpreferen...

From Autohotkey Site Documentation Go to the AutoHotkey Homepage. Click Download, once downloaded run the executable. During installation of AutoHotkey, you will be asked to choose from UNICODE or ANSI. In short, you would probably want to choose UNICODE. It has support for non-English letters ...

Assignment arguments appear at the end of an awk invocation, in the same area as file variables, both -v assignments and argument assignments must match the following regular expression. (assuming a POSIX locale) ^[[:alpha:]_][[:alnum:]_]*= The following example assumes a file file containing th...