∗ Change this behavior in Advanced settings. Select the corresponding legend color (1 for the first, 2 for the second, etc.)Īctivate Zoom Mode. Open the Select Color dialog to quickly choose a color. Hold and click on a country to quickly remove its color.∗ Hold and move your mouse over the map for the opposite of the Control action.∗ The buttons both have an inline onclick event listener attached to them that calls the same event handler, checkAnswer and accepts an argument of either true or false depending on which button was pressed.Hold and move your mouse over the map to quickly color several countries.∗ One thing to note when forking the view code using ternary operators is that you need to use the html function for each new fork. If there are no questions left then we show a GAME OVER message along with the player’s score. If there are then the question is displayed with two buttons, on for TRUE and one for FALSE. This ternary statement checks if questionNumber is less than the length of the questions array, which is basically checking to see if there are still any questions left to answer. Because the view is written using template literals, you can’t use if-else statements to fork code, so need to use ternary statements. Then we use a ternary operator to fork the view. After the title heading, we display the score using the score property of the State object. This is a slightly more complicated View than we saw in the earlier example, but most of it should be fairly self-explanatory. The easiest way to run the following example is to use an online code editor such as CodePen, or you can run it locally by installing the nanny-state package using NodeJS.Ĭopy the following code into the JS section of CodePen: import ` The easiest way to see how Nanny State works is to write some code! We’ll start with a basic example and then have a go at making something a bit more complex. How will the app data change when the user interacts with it? The Update function will be needed for this.How do I want the app data to be presented on the page? This will help you create the View function.What data do I need to store in my app? This will make up the properties of the State object.In fact, it can be summarised by asking yourself the following 3 questions: These 3 things are all you need to build an app in Nanny State. It is a single entry-point for updating the state and ensures that changes are deterministic, consistent and predictable. The Update function is the only way the state can be changed. It changes whenever the state changes and allows users to interact with the app. The View is a representation of the state as HTML. Even event handlers used in the View are methods of the state object. The state object is the single source of truth for your app – every bit of app data is a property of this object. Update – a function that is the only way to change the state and re-render the view.View – a function that returns a string of HTML based on the current state.State – an object that stores all the app data.Nanny State uses a one-way data flow model, made up of 3 parts: In this post, I’m going to explain how Nanny State works and then demonstrate what it can do with a couple of examples. It was inspired by HyperApp and has many similarities to to Elm. It also uses a single app-wide state object instead of each individual component having its own state. It’s similar to React, but with far less overhead and new syntax to learn. Nanny State is a tiny library that I wrote to help make it easy to build state-based web apps using Vanilla JS.
0 Comments
Leave a Reply. |