Friday, December 23, 2011

parameter handling and better code generation (Build 432)

GuineuIDE now correctly converts some of the built-in properties. Visual FoxPro uses lower case properties for all user-defined properties (ignoring _MemberData for the moment). Sometimes, however, those properties are stored in all upper-case. Guineu correctly identifies those as user-defined properties now.

Constants defined in the VCX or SCX include file are evaluated at compile time now. When you rebuild an existing project make sure to select Guineu > Clean up project name from the menu to force Guineu to rebuild all project files.

PRIVATE variables can be defined and are created in a truly private fashion. Undeclared variables are now PRIVATE, just like in Visual FoxPro. Missing variables raise an error message except when being assigned to. PARAMETERS creates private variables whereas LPARAMETERS is responsible for creating local variables.

Parameters can now be passed by value or by reference. Call the PARAMETERS() function to determine the number of parameters.

Some commands in Visual FoxPro are not relevant during program execution. EXTERNAL is a good example and is now supported by Guineu. Just like in the Visual FoxPro runtime this command does absolutely nothing. Previously, though, having the command in the code would raise a compiler error in Guineu due to an unknown token.

Code lines containing macro substitutions (& command) do not cause an error anymore. Currently, they are skipped at runtime since there's no tokenizer being part of Guineu.

Thursday, December 15, 2011

Changing the color of grid headers (Build 428)

Guineu Mobile implements BackColor and ForeColor for Header objects. Due to the (severe) limitations of the DataGrid control in the Compact Framework all headers must have the same settings for these properties. Guineu uses the setting in the last column to define the appearance of all headers.

There are also minor bugfixes in the STREXTRACT() function and the Listbox control.

Monday, December 12, 2011

.NET objects now First-class citizens in Guineu (build 426)

The most wanted features in Guineu were frequently ones that don't even exist in Visual FoxPro, such as making HTTP request, transferring files via FTP, placing phone calls, having a signature control, and so forth. Many of these made it into Guineu in form of a SYS(8xxx) function or a new base class that can be enabled.

Some of these features are still lacking such as accessing a bluetooth or serial printer, retrieving GPS information, obtaining phone book entries and text messages, and much more. Quite often there's sample code for C# or VB.NET for the Microsoft Compact Framework. Yet, often it's only few who request a particular feature. That makes it particular difficult to implement a solution that covers not only those developers particular needs, but also the needs of others in future scenarios.

This release is a major step forward!

We now support .NET objects in the same manner as native objects. The philosophy behind Guineu has always been to keep the look and feel of Visual FoxPro. Therefore you use .NET objects exactly like you would use native objects in Guineu or ActiveX controls in Visual FoxPro. There are no new commands or functions as the next sample demonstrates:

Local loForm, loButton
If Os(6) == "3"  && Windows CE
Set Classlib To \Windows\GAC_System.Windows.Forms_v2_0_0_0_cneutral_1.dll
Else             && Windows 9x, Windows NT
Set Classlib To C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Windows.Forms.dll
loForm = CreateObject("System.Windows.Forms.Form")
loForm.Text = "Hello"
loButton = CreateObject("System.Windows.Forms.Button")
loButton.Text = "World"
loForm.Controls.Add (m.loButton)

The SET CLASSLIB command now works for VCX, PRG and DLL files. CREATEOBJECT() searches .NET classes at the same time as searching for Guineu classes. You can access properties and call methods on .NET objects as you can do in Guineu objects. 

To load a DLL you need to pass the path to the DLL unless it is in the Windows search path. Please note that SET PATH TO is ignored, because Windows is in charge of loading the DLL. As with FLL libraries in Visual FoxPro you cannot embed these DLLs into the application.

On Windows Mobile it's a bit difficult to determine the actual location of the DLL file. By default, File Explorer hides any DLL and loading the Windows directory on a device can take some time. To find the file you can use the ADIR() function using a little Guineu program to list all installed GAC*.DLL files.


This is version one. There are naturally a number of things that don't yet work, some easy to fix, some more difficult.

NEWOBJECT() cannot load .NET objects yet. Adding a .NET control to an existing control also doesn't work. Guineu will always use the parameterless default constructor. Binding to events is not yet possible.

Guineu performs an automatic type cast based on the values you pass in. If there are multiple competing overloads of a method, you might not get the correct one. Similar, return values might be casted to objects when you expect them to be simple data types. This is especially an issue with Enumerations. CAST() does not support any of the native types. In fact, CAST() isn't even in the product yet.

Only public instance members are available. Static methods and private properties are not accessible. GETINTERFACE() doesn't work yet, nor does FOR EACH pick up the IEnumerable interface.

New features

The OS() function implements values 1-6 now. OS(6) returns the platform. This is 1 for Windows 9x, 2 for any Windows NT based system (NT, 2000, XP and later), and 3 for Windows mobile.


Repeatedly executing CREATE CURSOR would open a further cursor with the same alias.

ADIR() returned the wrong number of entries and wouldn't indicate directories.

SYS(2015) would not return a new value every call.

Builds 415-425

Since build 414 we made a number of changes, but I haven't been able to keep updating the blog. In this post I'll collect all those changes we made since January last year. Check back regularly, as I'll keep updating this post.

New features

STRCONV() is implemented with two new encodings. Values 17 and 18 provide a conversion between regular strings and URL encoded values ("A B" becomes "A%20B"). You need this with SYS(8009) to post back HTML forms to a web server.

SYS(8004) supports the "mssql" engine. Activating this engine switches to the regular SQL server client on mobile devices for SQLSTRINGCONNECT(). With this engine you can connect to a regular SQL server from any mobile devices. For data intensive processes this is a better solution than accessing DBF files across a WiFi.

GuineuIDE detects parameters to the Init event of an SCX form and produces the code to receive those in the generated PRG file and pass them on. This feature is a little fragile right now and only works for simply LPARAMETERS statements. Please report any code that doesn't pick up the parameter line. You might have to manually delete the *.scx.prg/fxp files to force GuineuIDE to regenerate the file.

APPEND supports the IN and BLANK clauses now.

MKDIR is now supported on the desktop and on the mobile platform.

Added support for Date, DateTime and Boolean fields to CREATE CURSOR.


We changed a number of file names to cope with a number of new supported platforms. Guineu.exe is now Guineu.Desktop.EXE, Guineu.runtime.dll has become Guineu.Runtime.Desktop.dll. Guineu.compact.runtime.dll is Guineu.Runtime.Mobile.dll. We dropped guineu.compact.exe completely, since it caused confusion about the proper way of creating a mobile application.

To use the new runtime version you have to rebuild your EXE using GuineuIDE.

Guineu detects when it's running in an emulator. When features aren't supported in the emulator, Guineu does not attempt to call them. This applies mainly to non-standard hardware.

Bug fixes

Sometimes Guineu would raise an error message referring to the record source being NULL.

Index files were kept open even when the table was closed. This made it impossible to delete the CDX file unless the application was closed.

Fixed crash when a class in a separate VCX or a procedure file was instantiated.

When a function or method returned a NULL string Guineu would sometimes crash when the result would be used in conjunction with the = or == operator.

Umlauts in procedure names no longer cause a crash.

Downloading binary files with SYS(8009) caused data corruption, mainly with DBF and CDX files. This has been corrected.

Added support for NULL values in cursors other than character fields.

COPY FILE handles subdirectories correctly now.

Known issues

Should you encounter an error message when launching the EXE on the device, please create a text file in the same directory as your application with the addition ".config". If your application is "myapp.exe", the file needs to be "myapp.exe.config". Put the following code into the config file:
<?xml version="1.0"?>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<assemblyIdentity name="OpenNETCF" publicKeyToken="E60DBEA84BB431B7" culture="neutral"/>
<bindingRedirect oldVersion="" newVersion=""/>

This was necessary due to an updated DLL. We are working on this issue. In future builds you do not have to create this config file.