Support String Operations on Rich Text while retaining styles

[wakaztahir]

User can perform following operations on the text when its a string

1. User can remove a text range
2. User can replace a text range
3. User can add text at an index

These operations are easier because text is a string , you can perform all these operations easily because String is a perfect representation of the Text user wrote , But not in the case of Rich Text

If you want to remove a range of text , You know the indexes , startIndex & endIndex

The problem is retaining styles

I propose that the following methods be added to RichTextState and be exposed publicly

1. removeTextRange(startIndex : Int,endIndex : Int) : Boolean
2. replaceTextRange(startIndex : Int,endIndex : Int,replacement : AnnotatedString) : Boolean
3. addTextAtIndex(index : Int,text : AnnotatedString) : Boolean

When user calls these methods , text range is removed / replaced , or text is added at an index , Without affecting the styles of other text

[wakaztahir]

It would be easier to accomplish after

setTextFieldValue(value : TextFieldValue) or setAnnotatedStringValue(value : AnnotatedString) #66

User could build his own text field value from the current styles from annotated string available in rich text state and set it himself by taking out some styles / adding more styles

And we could also provide helper methods that call setTextFieldValue or setAnnotatedStringValue under the hood.

[MohamedRejeb]

I think that this a good idea, maybe also users want to remove an entire line or something like that. I'll check these options. At the same time I don't want to provide too much public Api's to the users didn't get confused.