If a cell starts with number, contains text, and some values are auto-filled using this cell as base, for example with the Fill handle, the wrong Spreadsheet's autofill generator is used, and ordinal numbers are generated. Instead, the last number (if such) should be increased.

For example, if the cell value is "35'5" and the fill handle is used in order the values to next cells to be autofilled, the values are 35th, 36th and etc., instead of the correct ones which are: 35'6, 35'7,...

Steps to reproduce: 

1. Enter in a cell =Today()
2. Show Format Cells dialog and set Custom format "d"

Expected: The value is the day of the month.
Actual: The date is formatted as short date but has to be day of the month.

Wrong exception messages are constructed sometimes, due to problem in the internal Guard.ThrowExceptionIfTrue and Guard.ThrowExceptionIfFalse methods:

- Guard.ThrowExceptionIfTrue throws InvalidOperationException with text "<paramName> should be true.", instead the text should be "<paramName> should be false."

- Guard.ThrowExceptionIfFalse throws InvalidOperationException with text "<paramName> should be false.", instead the text should be "<paramName> should be true."

Available in LIB Version 2017.2.828.

Allow the customers to work with Shape objects.

Expose WorksheetUIUpdateContextBase.GetDataValidationRuleResult(CellIndex). This method is useful for creating optimized custom Data Validation Circles layers.

Available in LIB Version 2017.2.828.

COUNTA function is similar to COUNTIF function, but it only counts the non-empty cells. 

Description from Microsoft here: https://support.office.com/en-us/article/COUNTA-function-7dc98875-d5c1-46f1-9a82-53f3219e2509?ui=en-US&rs=en-US&ad=US&fromAR=1 .

Workaround: it should be possible to implement such custom function. See Custom Functions help article here: http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions .

When using the Fill feature through the dialog, the series are currently filled only for the cells, which are included in the selection. Introduce functionality to fill them without requiring a selection.

A custom implementation can be plugged through a custom dialog. A sample showing how to replace the default dialog with a custom one is available in the attachments of the item.

When a workbook protection is applied, changing the color of a tab in the sheet selector shouldn't be allowed.

Workaround: Remove the Tab Color item from the Items collection of the SheetSelectorContextMenu. 

If the RadSpreadsheet is declared as a child content in the RadBusyIndicator, there isn't any tab selected as active in the SheetSelector.

Workaround: Declare the busy indicator after the RadSpreadsheet not as its child.

For example, instead of:

<telerik:RadBusyIndicator>
    <telerik:RadSpreadsheet x:Name="radSpreadsheet" />
</telerik:RadBusyIndicator>

Do:

<Grid>
    <telerik:RadSpreadsheet x:Name="radSpreadsheet" />
    <telerik:RadBusyIndicator />
</Grid>

The default set of WPF UI controls measured in infinity results in the minimal size of the control. RadSpreadsheet should behave the same. This will help users to find out what is happening while debugging.

DataValidationRule is persisted after pasting a cell value which is copied from a cell without DataValidationRule applied. 

For example: Cell A1 has data validation rule applied. The cell A2 doesn't have. The value from cell A2 is copied to cell A1. The result is that cell A1 still has data validation, but it shouldn't.

LocalizableException with text "Format string is not in the correct format.", with inner ArgumentException "Format string is not in the correct format." is thrown. 

Currently the validation doesn't allow number format string starting with date or time formatting to have more that one section (for negative and zero numbers). Excel allows this type of number formats and if you set format like dd/mm/yyyy;[RED](#.##0); the positive numbers are visualized as dates, but negative numbers are visualized as numbers and their fore color is red.

Examples (including the final semicolons):

- ss;

- dd;

- dd/mm/yyyy;;

- mmm-yy;mmm-yy;_-* "-"??_-;_-@_-

When number format ends with N commas, the resulting number should be divided to 1000 N times. Instead, such commas are ignored. 

For example, if the format is #.0,, and the value of the cell is 12,200,000, the number should be displayed as 12.200.0

Implement options in fill handle which enable to choose the type of the auto filling, as in MS Excel. 

After drag-drop of the fill handle, a small UI control (drop down button like) appears which enables the users to choose whether the cell data should be copied, filled using series or other. Another option (also available in MS Excel), is to drag the fill handle with the right mouse button, which shows window with options.

Improve the editing in RadSpreadsheet with IME (input method editors). 

Problematic scenarios:

- Start typing:
When Japanese IME is chosen (for example) and the user starts typing while a cell is selected, the CellEditor should be in EditMode - the same behavior as if you are typing in English.

- Committing:
When the user is already in EditMode and typing with the Japanese IME, suggestions are listed in a popup. The user can than commit the sentence by selecting some of the suggested words with the mouse (by double-clicking on the suggestion) everything is correct and you continue to be in EditMode. However, if the user navigates to the suggestion and hit Enter (which is the most used case and it is somehow the native one) the editor goes out from EditMode to Inactive.

The MouseWheel event currently is handled in RadWorksheetEditorPresenterBase without a check if the Handled property is set to true.

Data validation does not validate values if they are not set using the cell editor. Pasting or auto-fill of invalid values will not produce data validation warning.

Among the other worksheet protection options, the customers can choose options like "Select locked cells" and "Select unlocked cells", enable or disable formatting options, insertion or deletion of different elements. These settings at the moment are not supported

Add API allowing change of the mouse cursor.

Currently indexed colors are imported only regarding the default color palette. Instead, when the entire palette is predefined using construct like:

  <colors>
    <indexedColors>
      <rgbColor rgb="00000000"/>
      ...

in styles.xml part, the indexed should be changed with the provided ones.

As this feature is not implemented, such colors are changed during the import.