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If you want a Form you create to have access to, and be able to use, an instance of a Class created outside the Form, you must take action to give the created Form a valid reference to the instance of the Class.
There are several ways to do that; here's an example of one way:
In the Form(s) you create define a Public Property that will hold a valid reference to the NMEA Class:
// in created Forms
// enable access
using NmeaInterpreter;
// to hold reference to instance of NmeaInterpreter
Public NmeaInterpreter theNMEAInterpreter { get; set; }
In the Form that creates the instance of the NmeaInterpreter, at the point where you have a valid reference to an instance of the NmeaInterpreter called 'myInterpreter, and you create the new Form:
// rough sketch of code
NMEAUsingForm newNMEAUsingForm = new NMEAUsingForm();
// insert the reference to the instance of NmeaInterpreter
newNMEAUsingForm.theNMEAInterpreter = myInterpreter;
At this point any method in the created Form(s) can access, and use, the instance of the NmeaInterpreter.
If you seek to aid everyone that suffers in the galaxy, you will only weaken yourself … and weaken them. It is the internal struggles, when fought and won on their own, that yield the strongest rewards… If you care for others, then dispense with pity and sacrifice and recognize the value in letting them fight their own battles." Darth Traya
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Greetings BillWoodruff,
Thanks for the reply. I am learning.
The question here is slightly different than is proposed.
Please See:
I have a class : public class NmeaInterpreter (well known);
I have a Form2() : where dealing with Serial Ports , and sending NMEA sentences from the GPS module to the class NmeaInterpreter ;
Now I have the main Form1() : where I should get the values (Lat, Longit, North, South, etc.), in TextBoxs ;
How it works:
1. After configuring the Serial Ports, I go out/hide the Form2(Serial Port) , and return to Form1 (main)
2. In main - Form1() - , I should receive sentences formatted sentences in the TextBox .
- Problems:
a) If I create in the Form2(Serial Port), a TextBox to test, I can easily receive, for example " Latitude ", etc.
b) But in Form1(main), where I should deal with events, I cannot do this (and I should receive direct formatted sentences from Class NmeaInterpreter).
Through the "Step Into", I noticed that I get the values in the constructor - public Form1() - but then leaves without sweeping methods. This is what the problem is!
c ) Why it works on Form2(Serial Ports ) and not on Form1(main)?
d ) Any error in the structure built ?
Well, I would like to thank the patience and your support
Jose
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I assume your problem is, that you send the NMEA sentences to a different instance of the NmeaInterpreter than you hooked up your event handler to.
- You should create only one NmeaInterpreter instance in Form1.
- Hook up your event handler there.
- Pass a reference of the NmeaInterpreter instance to Form2 either as constructor parameter or by using a property as already demonstrated by someone else.
- Then you can further adapt the settings and pass the NMEA sentences in Form two.
- Now you should receive the result in the event handler in Form1.
If that doesn't work, you could still consider storing the NMEA sentences in some List and passing them back to Form1. Then you can can send them to the NmeaInterpreter instance from Form1 and receive the result.
The good thing about pessimism is, that you are always either right or pleasently surprised.
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Are you the same person, named Jose, who is also Member jfxdasilva [^], and who previously posted an almost identical question: [^] ?
If you seek to aid everyone that suffers in the galaxy, you will only weaken yourself … and weaken them. It is the internal struggles, when fought and won on their own, that yield the strongest rewards… If you care for others, then dispense with pity and sacrifice and recognize the value in letting them fight their own battles." Darth Traya
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I am so sorry for that. I do not understand what's happening. I'm Jose and jxfdasilva is abbreviation of my name. If there is a way we can delete the duplicated post, thanking, but the strange thing is I'm posted once.
Thank you.
Rgds
Jose
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Don't worry, I'm not "accusing" you of anything; I'm just curious. It's possible a server error happened.
Did you find the answer about how to make the NMEA Class instance available to other Forms was useful ?
yours, Bill
If you seek to aid everyone that suffers in the galaxy, you will only weaken yourself … and weaken them. It is the internal struggles, when fought and won on their own, that yield the strongest rewards… If you care for others, then dispense with pity and sacrifice and recognize the value in letting them fight their own battles." Darth Traya
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From what I understand of your post:
You have 2 forms each doing some seperate work with the NmeaInterpreter? I'm curious how that would work based on your code in the post. You just create a new NmeaInterpreter instance and hook up an event. (I assume by now you are using += to hook the event up) Don't you need to define some properties of the receiver (port, type, ...) should the class be "started" (just like a timer object needs the "Start" call to actually launch).
In case you do have 2 seperate forms each doing some part of the work, take out the NmeaInterpreter in another class and pass along the data from that class. You can use new delegates/events for that, and it keeps your send/receive logic in one place, which makes more sense.
I have never seen this construct:
TestBox.Text latitude.ToString = ();
And I'm not sure why you'ld call the ToString on latitude other than a creating a good chance in an exception being thrown.
What's wrong with
TestBox.Text = latitude; ?
hope this helps.
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Greetings V
Thank you for your explanation. I don't know why, but when a post the code, it changed. I had already rectified in other post.
Please See:
I have a class : public class NmeaInterpreter (well known);
I have a Form2() : where dealing with Serial Ports , and sending NMEA sentences from the GPS module to the class NmeaInterpreter ;
Now I have the main Form1() : where I should get the values (Lat, Longit, North, South, etc.), in TextBoxs ;
How it works:
1. After configuring the Serial Ports, I go out/hide the Form2(Serial Port) , and return to Form1 (main)
2. In main - Form1() - , I should receive sentences formatted sentences in the TextBox .
- Problems:
a) If I create in the Form2(Serial Port), a TextBox to test and I could easily receive, for example " Latitude ", etc.
b) But in Form1(main), where I should deal with events, I cannot do this (and I should receive direct formatted sentences from Class NmeaInterpreter).
Through the "Step Into", I noticed that I get the values in the constructor - public Form1() - but then leaves without sweeping methods. This is what the problem is!
c ) Why it works on Form2(Serial Ports ) and not on Form1(main)?
d ) Any error in the structure built ?
Well, I would like to thank the patience and your support
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I'm still not sure how your setup is.
But in Form 2 you set some info (like serial port), how does Form 1 know about it?
You say yourself in a) Putting everything in one class works. I think you might have an NmeaInterpreter instance in form1 and another (different) one in form2
Here's what you should do:
1. Write a wrapper for the NmeaInterpreter class.
2. create delegates/events in that wrapper like "info_received" or something.
3. Setup the properties like serial port, etc in form 2 and pass it to the wrapper.
4. The wrapper should receive the message. in the handler, fire the event made in step 2.
5. make sure form 1 is subscribed to the event "info_received".
Note: depending on how the delegate/event is created you can get the latitude/longitude information. I prefer events with no arguments and just setting the properties before firing the event in the wrapper. When the handler from form 1 launches it just reads out the properties of the wrapper class.
I would encourage you to use the wrapper method, because that will be the single point of entry for your project concerning the third party library (the NmeaInterpreter)
If this does not answer your question, try to go back to your original post and try to rephrase the actual problem and what your trying to achieve. It is very hard for us to understand.
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Thanks for the help V.
I'll try and then inform you of the results.
I apologize for not being explicit in my explanation but tried my best. I'll try to take a snapshot if it helps.
I would like to understand in the academic point of view, why despite generate trigger events in NmeaInterpreter class (this is a fact because I can receive data in Form() Serial Port), cannot directly receive in other created Forms(), despite instantiate, create methods, etc... Only in Form() where is the Serial Port that is possible. Is this means that I cannot receive events generated in Class NmeaInterpreter, in 2 or more Forms() simultaneously?
However, if you use the example (GPS - Deriving British Ordnance Survey Grid Reference from NMEA data), and create another Form(), and in this created Form() attempt to receive events directly from NmeaInterpreter class, instantiating, creating methods, etc... you will see. This example is the closest I can give.
Finally, I wish to inform you that this is purely academic, because I like to intrinsically understand how things work, and these challenges are very helpful.
Kind regards
Jose
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Good evening everyone
although still not understanding why it cannot receive events directly out from the Form() that deals with the Serial Port, got it working using some advice left here. Now a problem arises and I would like to count on your collaboration.
I created a variable in the Form (Serial Port), and get its value in Form (main). From the main, it sends the string to the Class that handles the data, and consequently I can see the textBox no the Form(main).
To do this I created a button that when clicked, sends a stream of data, but then it Stops! Thus, I have always to update by click. Any way to have continues receiving the data stream?
P.S: without using a Timer.
Thank you for the support.
Jose
modified 18-Dec-13 16:24pm.
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hi,
i want to create a menustrip in right hand side like treeview.
i am using visual studio 2010, i drag and drop the menustrip, its automatically going upside of the window and i am check all properties there is no chance to display in right hand side...
i want to create like..
window have two sides ( left and right )
right side have the menu strip like treeview,that is have click event
and click the particular menu corresponding window shows the left side
Regards
Anand Rajan
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look for the Dock property of the control or the HorizontalAlignment if you are using WPF
Never underestimate the power of human stupidity
RAH
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thanks
actually the sub menu are not visible that is inside id the menu...that is my problem i want show all sub menus with menu like tree view...
that is possible..
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don't know how to do that by own code but i can tell that the devComponentsDotNetBar2 has such elements in it 
Maybe you check that out and give it a try
if(this.signature != "")
{
MessageBox.Show("This is my signature: " + Environment.NewLine + signature);
}
else
{
MessageBox.Show("404-Signature not found");
}
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Hi all,
Am going to develop a website which has to handle different kind of users and there is an option to enter the different kind of data(real estate information). Each
real estate information can be considered as an object .Recently I read about design patterns. How to determine whether i need to use a design pattern or not in and which one I need .
Regards,
Jeena
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Decide on the tech you want to use, find all the design patterns related to that tech, write all the name on a piece of paper and stick them in a bowl. Pick one!
I thought I had made the right decision moving to Silverlight and MVVM!
Never underestimate the power of human stupidity
RAH
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Design Patterns are like programming languages:
They don't solve your problem by themselves, neither they guaranty that your design decisions are an appropriate solution for the problem. Stick with a design pattern you like, and most important, understand.
Another fault that seems to happen very often is that people pick a design pattern and then later start to abandon it, and switch to another one - Which leads to crapcode and mass confusion, sooner or later.
I found a nice page summing up all of the important aspects of design patterns:
Patterns are not the panacea of program design. They do not replace traditional object-oriented analysis techniques like CRC cards or use-case modeling. To use an architectural analogy, analysis lets you determine that your house needs 200 amps of electricity. Patterns let you determine how the wiring will be installed.
Patterns do help you think about the problems you may encounter while designing a system. Therefore, a generic, pattern-based solution is often more robust than a solution designed by one individual to solve a specific problem.
Given the number of design patterns in common use (as well as many more being invented and discovered almost daily) it can sometimes be hard to choose the pattern that suits your needs.
The first thing you should decide is whether the problem is fundamentally creational, structural, or behavioral. Some problems, of course, have aspects of two or even three, and may require you to mix and match patterns.
Veni, vidi, caecus
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A design pattern is just a fancy term for a particular architecture that some experienced and clever people have determined is good for a particular use case. If your use case is one that has been done many times and has well defined patterns for it, then you should consider modelling your own design on one of those patterns. They are one step more specific than architectural guidelines like layering, dependency isolation, boundary interfaces etc.
Your application sounds like a fairly typical 3 tier web application and if you're starting from scratch in a .Net environment then you will probably want to use ASP.net MVC with Entity Framework or a similar ERM (e.g. NHibernate). MVC is a well specified and well tested design pattern that generally works well for that kind of application.
The important thing to remember about patterns is that they are not a prescriptive set of instructions, they're guidelines and example designs for particular scenarios. If you don't want to do quite the same thing that they did, it's natural that your design might want to be slightly different. What patterns give you is a set of initial starting points that you can use to inform your design process.
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Just write the best code you can; either it will match an existing Pattern or it won't, no big deal.
Naming Patterns isn't really for a developer's own use; it's for developers to easily communicate ideas amongst themselves.
Think of it like ordering a pizza; the pizza shop may have a list of "named" styles, like "veggie", "meat lovers", "hawaiian", etc. but you are also free to specify toppings as you please. It may be that the set of toppings you choose happens to match one of the named styles that you aren't familiar with and the clerk may then tell you that you could just order the "greek" next time. Saying "greek" the next time will save time and may reduce confusion, but does not carry any more information than you provided the first time. Likewise, if you make a pizza at home, you wuoldn't tell yourself that you want to make a "greek" pizza, you'd would just make a pizza any way you want, and it may turn out that it matches the "greek" pizza that that pizza place offers.
As a side note, when I was first introduced to "hawaiian" pizza it had ham and pineapple. When I ordered "hawiian" pizza from a different place, the clerk asked, "well what exactly does 'hawaiian' pizza mean to you?"
Also bear in mind that not all developers understand Design Patterns exactly the same. The "Gang of Four" book is the definitive reference. Also remember that just because the Pattern has a name, it isn't necessarily a good idea.
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Design patterns will help you structure your code.
However, if you write good code, you could probably do without design patters.
Remember a few basics like high cohesion and low coupling.
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As you can use a delegate to set the value of a property, you can obviously use a multicast delegate to set the properties of a class.
Or you can use a binding.
What are the pros and cons of each method?
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Delegates and (data) binding are useful in different circumstances.
Although, both can be used to change property values at runtime, multicast delegates are useful when you want to invoke multiple operations (rather than bind data) at runtime. Binding on the other hand is useful to directly set the values of properties at runtime. Binding a property to a value will not help you execute methods.
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They are two distinct ways of communicating between entities, although you can implement data binding manually (for example where it isn't provided by the framework) using delegates and INotifyPropertyChanged fairly easily.
Data binding is typically used for a data view, generally a UI. Its purpose is to ensure that the data in the model matches what's being shown in the view, to put it in MVC/MVVM terms. No logic should happen in a data binder, although format conversions are acceptable (in WPF you can provide this as a binding argument, in WinForms you have to create a view model that's tightly bound to the view and put the conversion in there – obligatory self promotion).
Delegates are a general method to trigger code off another object's event. I'm assuming that in this context you're talking about handling change notifications on one object and updating another object as a result. This is quite similar to data binding, but the difference is that while data binding typically creates a 'vertical' binding (i.e. the view layer and model or view-model layer classes of the same concept), notifications between data objects is a 'horizontal' binding (i.e. classes in the same layer but relating to different concepts). You'd typically use delegates for this, with the handlers in a central controller class, because there is generally calculation or business logic required beyond simply assigning properties, as well as because data binding isn't typically available in such a scenario.
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