I have generated a solution in C# 2010 by way of the Artinsoft conversion from VB6.
When I open the new solution in C# I right-click on the forms but there is no "View Designer" option. I assume this is because something is failing to compile. What could be the problem and how should I fix it?
Try a clean and rebuild
Make sure you have proper designer.cs file
Make sure the initialize method is called from the constructor of your Forms.
Make sure if there are any custom dlls they are in right places.
Better create a new app in Windows forms and check how the things are arranged. so that you can compare the conversion.
I would not expect that from a failure to compile, but rather a failure to convert properly. Even if the class doesn't compile, if it's a form you shouldbe able to see and edit the form portion.
The reason should be marked in the error list if it's failing to compile. It's more likely that it's created it as just a class (that doesn't inherit from Form).
Check that there's a MyForm.Designer.cs (where your form name is MyForm) and also check that the declaration of the class in MyForm.cs inherits from form
public partial class MyForm : Form
If this isn't the case, it hasn't converted properly, so you may have to inherit from form, drop on the UI controls again and hook them up to any events
Have you tried running Visual Studio as Administrator (elevated rights)?
Can you try Shift+F7 key combination?
Related
I've had this long time problem that I can't view as text the main form for a project I inherited. Even if no other forms are open.
How can I debug the cause of this error message? What options do I have to fix it?
I found one related newsgroup post http://embarcadero.newsgroups.archived.at/public.delphi.ide/200906/0906193960.html but this only addresses the form inheritance cause, and doesn't explain anything about linked modules. I don't believe I'm using form inheritance.
I do have a DM (data module) for the project, and the form does load a couple of images from the dm through properties of a TTreeView on the form--does having a data module automatically mean I can never view as text a form in Delphi (aside from viewing the form as text in notepad)? It doesn't seem to matter whether my DM is open or closed in the IDE.
I also found one SO question with a related title (Module %s has open descendants or linked modules. can not reload) but the question itself and it's answer is not particularly relevant.
This is sometimes caused by a form that inherits from another form in your project (or the gallery) (known as Visual Form Inheritance in the documentation, IIRC). The IDE doesn't know how to find the base class for the form; it needs that opened before the descendant form. For instance, this can cause the same error if the unit containing TMyBaseForm isn't opened first in the IDE, particularly if the base (ancestor) unit is not included in the project first:
unit SpecialForm;
interface
uses
Forms, { all the other usual stuff }, BaseForm;
type
TMySpecialForm = class(TMyBaseForm)
private
public
end;
You can tell if this is the case by looking at your form's class declaration - if it descends from anything other than TForm, this is probably the cause of the error.
(Another instance of it happening is often when using a datamodule, because the base TDataModule .DFM isn't available. Attempting to view the datamodule .DFM as text will cause this error every time; the solution is to close your project and use an external editor such as Notepad or Notepad++ to edit the .dfm for your datamodule.)
I've had this issue occasionally, perhaps when I've used Frames, but my latest instance didn't involve Frames nor Data Modules nor inherited forms.
After an enormous amount of work creating a copy of the form (which copy didn't have the problem) and renaming the original unit and the form itself (which initially seemed to solve the problem), it turned out to be a live binding between forms.
Specifically, in my FMX application Form A has an options page with a TSpinBox that allows the user to set the minimum value for a TTrackBar on Form B (which was the form giving me grief). So the TSpinBox.Value was set to update the TTrackBar.Min field by means of a live binding. Closing Form A, or removing that live binding (and replacing it with an event handler to do the same thing) solved the problem.
I'd like to call upon the answer of Phillip J. Rayment and ADD that you don't have to have live binding to have this problem occur. It's sufficient to have custom control (class) of which you have an instance in another form. Then the RLink32 problem can appear and won't be solved until you close the form where you have the instance. The problem I experienced gave the following messages:
-RLink32 (during building)
-Access violation in module designide160.bpl` (if I made a modification to the problematic form)
-The module has open descendants or linked modules” error (if I tried to 'View as Form')
When designing a TForm, a line is added to the form's unit declaring the form object...
var
frmMyForm: TfrmMyForm;
I don't need this form auto-created, and I intend to create multiple instances of it, and to make sure I don't make the mistake of using this declared form, I commented it out...
//var
//frmMyForm: TfrmMyForm;
I was wondering if this is safe to do? I don't see any problems, and the form designer still works fine. But could there be some trouble if I leave this out completely?
This is a very common scenario when using form inheritance. You normally don't want to instantiate derived forms from the middle of the inheritance chain.
The only place where these form variables are used (besides your code perhaps) is the dpr file and that only when the form is autocreated.
So, no problem to remove the declaration.
To explain my problem, an example is better.
I have an ASP.NET MVC 3 controller action who return a view with an object as a Model.
This object, contains some business properties used by the view like a list of contacts, for example.
If i call a property of my object in the view (from Model.) and, after that, I change this property name, the debugger of visual studio say nothing.
However, this one should alert me that I try to load, in the view, a property who doesn't exist !
Moreover, when i compile this project, it passes until i try to render the view !
Is there a way to check that from visual studio ?
Thank's by advance !
You could enable compilation of your ASP.NET MVC views by putting the following in your .csproj:
<MvcBuildViews>true</MvcBuildViews>
This way you will get a compile-time error.
You can compile in Release mode to highlight all deal breakers. takes a bit longer to compile but catches everything, right down to properties in Views and even takes you to the line in the View that's causing the problem(s).
I have a runtime error happening in the rtl Streaming in of a form, causing an exception EClassNotFound to be raised, while doing TReader.ReadRootComponent. The particular error message is "Class not found TActionList".
What is odd is:
My main form uses Action list.
For fun, I added ActnList.pas (from the VCL source folder) to my project, to try to fix it.
This happens to me when instantiating a form that I had working until a few minutes ago. The change that I made was in some sub-frame code: I removed all its implementation section code with an ifdef marker, because I am mocking up some frames, for unit testing and prototypes.
I tried adding the action list class to the project, and I tried with and without various compiler and link options, and yet, I still get this exception. Obviously something weird is up. There must be another weird way to get this problem.
In fact, it seems there is something really weird going on. When this error is raised, I get the following call stack:
rtl.Classes.ClassNotFound('TActionList')
rtl.Classes.TReader.FindComponentClass(???)
rtl.Classes.FindExistingComponent
rtl.Classes.TReader.ReadComponent(nil) /// NIL!? WHAT!!!!!
rtl.Classes.TReader.ReadDataInner(???)
rtl.Classes.TReader.ReadData(???)
rtl.Classes.TComponent.ReadState(???)
vcl.Controls.TControl.ReadState(???)
vcl.Controls.TWinControl.ReadState($60B9CF0)
vcl.Forms.TCustomForm.ReadState(???)
rtl.Classes.TReader.ReadRootComponent($606EB90)
rtl.Classes.TStream.ReadComponent($606EB90)
rtl.Classes.InternalReadComponentRes(???,???,$606EB90)
rtl.Classes.InitComponent(TComplexFormContainingFrames)
It seems the nil is intentional, in TReader.ReadDataInner(Instance:TComponent):
while not EndOfList do ReadComponent(nil);
Update: I believe the answer to this question is to understand "serialization contexts" as Mason has mentioned. And, it's time to admit my own Stupidity: I removed the parent of the frame from the project, not realizing it was the parent of the frame. I worked around it being missing by stubbing the type declaration for TMyFrameParent as TMyFrameParent = class(TFrame), and this in turn lead to the condition in question. I am leaving the question here because I think it might be really handy in future to note when this exception occurs in arcane cases, and how to fix it. In particular, Mason has a really interesting bit of information about "serialization contexts" and how they apply to class-name-finding.
It means that the class wasn't found in the current deserialization context. Not all existing classes are registered for all loading. Each form class has RTTI containing references to the components it uses. To get this to work, make sure that your form (or frame, if this is a frame) declares at least one TActionList before the private tag:
TMyForm = class(TForm)
ActionList: TActionList;
OtherComponent: TSomeComponent;
private
//whatever
public
//whatever
end;
Use Classes.RegisterClass to register classes you want to use with the streaming system. Quote from the doc
Form classes and component classes that are referenced in a form declaration (instance variables) are automatically registered. Any other classes used by an application must be explicitly registered by calling RegisterClass if instances are to be saved. Once classes are registered, they can be loaded or saved by the component streaming system.
It seems that this happens when you copy a frame from one project to another project, and that frame inherits from something, and you fake the inheritance, but leave the "inherited" item descriptions in the frame dfm, items like this:
inherited ActionList: TActionList
Left = 520
Top = 576
end
This in turn results in the "current deserialization context" that Mason talked about, not containing the class. One fix is to change Inherited to object in all the above cases.
There is another way to get this error: put 'public' at the top of a form definition class. By default class members are 'published'. I accidentally added 'public' to the top of a form declaration and it produces multiple 'Class not found' exceptions at run-time.
I got a "EClassNotFound" error when I had a TLabel declaration present in my DFM file but there was no declaration for it in the corresponding PAS file. Somehow the form editor screwed up.
The error was not visible until I deleted all labels from my form except that particular "corrupted" one. It was difficult to hunt it down because that label was hidden under a panel.
One easy fix is to cut (ctrl+x) that label (once you find it) from the form and paste it back. This time the form editor will correctly insert a declaration for it in the PAS file.
There is yet another way to get this error: I have put 'private' at the top of a form definition class (because none of the elements were used outside the form).
So same like in previous answer (by Server Overflow): by default class members are 'published' and if you change visibility of a form declaration it produces multiple 'Class not found' exceptions at run-time.
There are some program tools such as WinSpy++ which will allow you to hover over the Handle of any Control/Component and return the Class Name of that Handle. So for example, if I dropped a TMemo on a Delphi Form and compiled the Application, if I used WinSpy++ and hovered over the Application (above the Memo), it will reveal the Class Name of the Editor as TMemo.
Now, suppose I dont want anybody using such a program to determine the Components I am using in my Application, how would I prevent Class Names from showing up in a tool, such as WinSpy++?
I ask because I dont want anyone to easily create clones of any Applications I may create and release, if the Class Names of the Components I am using are discovered it would make their task easier because then they know what to use.
Simply put, how can I hide the Class Names of the VCL I use in my Delphi Application from external viewer tools like WinSpy++.
WinSpy++ can be found here: http://www.catch22.net/software/winspy
To add, I know I can custom derive these components to change the Class Names to my own, but their must be an easier way.
You could override CreateParams and put your own class name into Params.WinClassName. The default behaviour is implemented in TWinControl.CreateParams:
with Params do
...
StrPCopy(WinClassName, ClassName);