[Tizen] Adds Opt-in Init

[rookiejava]

Description of Change

This PR introduces a new Forms.Init() that allows you to customize initialization options. (in the same way as android backend - #6087, #6149)

Issues Resolved

None

API Changes

Added:

• void Forms.Init(InitializationOptions options)

Platforms Affected

• Tizen

Behavioral/Visual Changes

This change does not affect the behavior of existing Forms.Init. It's just an addition to the new Forms.Init() having InitializationOption to enable partial init. For example, using this, you can register a certain type of renderers at initialization time.

How to register all default renderers provided by Tizen backend.

// Creates the handler attributes
var assembly = Assembly.GetAssembly(typeof(Forms));
object[] attributes = assembly.GetCustomAttributes(typeof(HandlerAttribute), true);
var handlerAttributes = new HandlerAttribute[attributes.Length];
Array.Copy(attributes, handlerAttributes, attributes.Length);

// Creates the InitializationOptions
var option = new InitializationOptions(app, true, handlerAttributes);

// Initiailize
Forms.Init(option)

How to get handler attributes from a certain type.

//Get Assembly
var assembly = Assembly.GetAssembly(typeof(Forms));

//For renderers for each controls such as Button, Label, ...
//By default, 31 default renderers are provided by Tizen backend
object[] renderers = assembly.GetCustomAttributes(typeof(ExportRendererAttribute), true);

//For Image source handlers such as FileImageSource, StreamImageSource,...
//By default, 3 default image renderers are provided by Tizen backend
object[] imageHanders = assembly.GetCustomAttributes(typeof(ExportImageSourceHandlerAttribute), true);

//For Cell handlers such as TextCellRenderer, ImageCellRenderer,...
//By default, 5 default cell renderers are provided by Tizen backend
object[] cellRenderers = assembly.GetCustomAttributes(typeof(ExportCellAttribute), true);

//For GestureRecognizer handler such as TapGestureHandler, PinchGestureHandler,...
//By default, 3 default gesture recognizer handlers are provided by Tizen backend
object[] gestureHandlers = assembly.GetCustomAttributes(typeof(ExportHandlerAttribute), true);

Before/After Screenshots

Not applicable

PR Checklist

• Has automated tests
• Rebased on top of the target branch at time of PR
• Changes adhere to coding standard