Tutorial by Examples: w

Incorrect Code Sub DoSomething() GoSub DoThis DoThis: Debug.Print "Hi!" Return End Sub Why doesn't this work? Execution enters the DoSomething procedure, jumps to the DoThis label, prints "Hi!" to the debug output, returns to the instruction immediately afte...

Incorrect code Sub DoSomething() Dim row As Integer For row = 1 To 100000 'do stuff Next End Sub Why doesn't this work? The Integer data type is a 16-bit signed integer with a maximum value of 32,767; assigning it to anything larger than that will overflow the type and ...

Incorrect code Sub DoSomething() Dim foo As Collection With foo .Add "ABC" .Add "XYZ" End With End Sub Why doesn't this work? Object variables hold a reference, and references need to be set using the Set keyword. This error occurs whenever ...

you can set a Jekyll environment and value, when build time JEKYLL_ENV=production jekyll b JEKYLL_ENV=production jekyll build JEKYLL_ENV=production bundle exec jekyll build if your code contains the bellow snippet, analytics.html will not be included unless your building with JEKYLL_ENV=...

To create a Java lambda using the GUI, first make sure you have your distribution zip ready. You will also need an AWS account that can create lambdas. Switch to the AWS Lambda, dismiss the introduction screen (or read the Get Started documentation) and press the button Create a Lambda Function. ...

Probably the most common way to invoke a Lambda is to use API Gateway, which maps a REST call to the lambda code. You can add multiple triggers to your Lambda during at any time, including when creating a new lambda. If you are familiar with API Gateway, you can associate any method with a deployed...

UITabBarController building in Swift 3 Change image color and title according to selection with changing selected tab color. import UIKit class TabbarController: UITabBarController { override func viewDidLoad() { super.viewDidLoad() self.navigationController?.isNavigat...

Type Casting Type casting is a way to check the type of an instance, or to treat that instance as a different superclass or subclass from somewhere else in its own class hierarchy. Type casting in Swift is implemented with the is and as operators. These two operators provide a simple and express...

Here is a Rules example in Rules export format: { "rules_display_userpoints_after_updating_content" : { "LABEL" : "Display userpoints after updating content", "PLUGIN" : "reaction rule", "OWNER" : "rules", &qu...

public static class MyHelpers { public static MvcHtmlString MyCustomDiv(this HtmlHelper htmlHelper, string text, object htmlAttributes = null) { var mainTag = new TagBuilder("div"); mainTag.MergeAttributtes(htmlAttributes); mainTag.AddCssClas...

Let's create a small piece of code that throws an exception: private void button1_Click(object sender, EventArgs e) { string msg = null; msg.ToCharArray(); } If we execute this, we get the following Exception and stack trace: System.NullReferenceException: "Object reference not...

Django Model Form with Django Class Based view is a classic way of building pages to do create/update operations in django application quickly. Within the form we can put methods to execute tasks. Its a cleaner way to put tasks in forms rather than putting in views/models. To give an example using ...

Incorrect code Sub DoSomething() On Error GoTo CleanFail DoSomethingElse CleanFail: Debug.Print Err.Number Resume Next End Sub Why doesn't this work? If the DoSomethingElse procedure raises an error, execution jumps to the CleanFail line label, prints the error number, a...

To restrict the characters that can be typed into an entry widget, only numbers for instance, a validate command can be added to the entry. A validate command is a function that return True if the change is accepted, False otherwise. This function will be called each time the content of the entry is...

The connection between the widget and the scrollbar goes both ways. The scrollbar needs to be expanded vertically so that it has the same height as the widget. text = tk.Text(parent) text.pack(side="left") scroll_y = tk.Scrollbar(parent, orient="vertical", command=text.yview...

The principle is essentially the same as for the Text widget, but a Grid layout is used to put the scrollbars around the widget. canvas = tk.Canvas(parent, width=150, height=150) canvas.create_oval(10, 10, 20, 20, fill="red") canvas.create_oval(200, 200, 220, 220, fill="blue")...

Ubuntu: lshw is a small tool to extract detailed information on the hardware configuration of the machine. It can report exact memory configuration, firmware version, mainboard configuration, CPU version and speed, cache configuration, bus speed, etc. $ sudo lshw | less (or more) $ sudo lshw -ht...

Follow following steps to try out a sample application on AWS ECS service as a proof of concept. Login to AWS management console and go to AWS service catalog - > Compute - > Ec2 Create a VM(EC2 instance) using amazon linux 64 bit OS, this we will use to configure docker, git, AWS ECS agen...

In this example, one of two different ImageViews should be translated from the ChooserFragment to the DetailFragment. In the ChooserFragment layout we need the unique transitionName attributes: <ImageView android:id="@+id/image_first" android:layout_width="wrap_content...