This means that your Preview renders the layout with some content which does not get shipped with your app. In this case we use tools:text="Title" and and voilà!Īttributes declared with the tools prefix work exactly as the android ones but only for preview. By using the tools namespace instead of android, while declaring xml attributes, allows you to specify attributes that are going to be used only while in preview. When creating a layout that uses any content related view, a good practice would be to populate it only while in preview. Even when the code compiles without issues, no one can make sense of the layout without looking at the XML code. This is a common issue when dealing with dynamic content. The problem in this case is that the TextView and ImageView do not have any content to display. The naive solution to this issue is to test the layout on-device, where you actually have that data. You quickly realise that, since the content is dynamic, the Preview tool cannot populate the screen and you see nothing. Here is a list with the most frequently Preview issues I have faced and their solutions for easier development: Issue #1: The Preview looks emptyĪssume you have a layout whose content is to be filled in with data obtained from the backend. Unless you know its limitations and how to overcome them, that is!
It also allows you to see the different configurations of your layout, such as how would it look like while in portrait or landscape, or how does that TextView look on multiple locales such as English, German or Greek.Įven though the preview tool is powerful and can make your development days a breeze, it can also make your life miserable and frustrating. The Layout Preview displays a representation of how your XML code will be displayed on the device. Android Studio's Preview tool helps you implement those great designs and iterate through them quickly without even the need to run your app. Chances are you have at least one layout file for every Activity you have in your project. XML layouts are probably the most frequently used resource in Android development. The Layout Preview can be accessed by pressing the Preview tab on the right
This post talks about how to get the hang of the Preview tool and design layouts that can be grasped at the first glance. As powerful as this tool can be, it can lead to some misleading errors driving the developer crazy. Android Studio comes with a powerful tool that helps you understand how your layout files are going to be rendered on the user's device.
0 kommentar(er)
