In this case, ordinary keyboards in operating systems cannot meet the needs and the need to design and build custom keyboards increases. In this case, if the designed keyboard is separate from the application and the application is not launched within the application, it cannot meet the need properly. So the only solution for this set is to design a custom keyboard that can be launched inside the application so that it can meet all the needs. In this article, we describe how to design and build a custom keyboard. If you want to design a custom keyboard for built-in applications , it is recommended that you follow this article.The best way to design and build a custom keyboard to run within the app itself is to go native. By following this path, you can easily design a keyboard that can be launched inside the application and other users do not need to download that keyboard separately to use this keyboard. In designing a custom keyboard using Xamarin.Forms, we need the Custom Renderer option. This option is used to control entries.The Xamarin.Forms version must be high to design and build a custom keyboard, with the OnFocusChangeRequest method. Any version of Xamarin.Forms that has the OnFocusChangeRequest method is suitable for custom keyboard design. Using this method, we create a custom control that has a bindable attribute. This feature is used for connection and this feature with features such as EnterCommand and ICommand causes the action connection to be pressed on the keyboard button. Therefore, to build the keyboard, we have to use the version of Xamarin.Forms, which has the OnFocusChangeRequest method, because using this method, we will create a connectivity feature that turns the pressing of a key on the keyboard into action.

All the Android packages required to design and build a custom keyboard are as follows:

- Xamarin.Android. Support.Compat

- Xamarin.Android. Support.Core.UI

- Xamarin.Android. Support.Core. Utils

- Xamarin.Android. Support.CustomTab

- Xamarin.Android. Support.Design

- Xamarin.Android. Support.Transition

- Xamarin.Android. Support.v4

- Xamarin.Android. Support.v7. AppCompact

- Xamarin.Android. Support.v7. CardView

- Xamarin.Android. Support.v7. MediaRouterTo be able to design a custom keyboard for Android using Xamarin.Forms , all of the above Android packages must be present.1- The first thing we need to do is write code that supports the bindable attribute and causes the action to be connected to the key. 

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