Assuming the following *.ui.xml file:
<ui:UiBinder xmlns:ui='urn:ui:com.google.gwt.uibinder'
xmlns:g='urn:import:com.google.gwt.user.client.ui'>
<g:VerticalPanel>
<g:Label ui:field="Label1"></g:Label>
<g:Label ui:field="Label2"></g:Label>
<g:Label ui:field="Label3"></g:Label>
</g:VerticalPanel>
If I now want to add ClickHandlers to all three Labels like this:
#UiHandler("Label1")
void handleClick(ClickEvent event) {
//do stuff
}
#UiHandler("Label2")
void handleClick(ClickEvent event) {
//do stuff
}
#UiHandler("Label3")
void handleClick(ClickEvent event) {
//do stuff
}
I get an error, because I have 3 methods with the same name. Is there a way around this, other than creating custom widgets and add those to the VerticalPanel?
There is also an option to use one annotation for multiple Widgets
#UiHandler(value={"clearButton_1", "clearButton_2"})
void handleClickForLabel1(ClickEvent event) {
//do stuff
}
Just name them different things. The important part that helps GWT recognize what kind of event you want to handle is the ClickEvent, but the method name doesn't matter.
#UiHandler("Label1")
void handleClickForLabel1(ClickEvent event) {
//do stuff
}
#UiHandler("Label2")
void handleClickForLabel2(ClickEvent event) {
//do stuff
}
#UiHandler("Label3")
void whoaSomeoneClickedLabel3(ClickEvent event) {
//do stuff
}
I ran in to this situation and found that event.getSource() only gives an instance of the source object not its name. I had to cast it and get its title to identify the source object. In my case I'm using MaterialImage and setting its title in the UiBinder.
Example:
UiBinder code
<m:MaterialImage url="images/icons/simpleLine.svg" ui:field="simpleLine" title="simpleLine" />
<m:MaterialImage url="images/icons/smallDashBigGap.svg"ui:field="smallDashBigGap" title="smallDashBigGap" />
In Java
Object object = event.getSource();
if (object instanceof MaterialImage) {
MaterialImage image = (MaterialImage) object;
String type = image.getTitle();
if (type.equals("simpleLine")) {
...
}
I wish there is a better way but that's all I could work with.
Related
I have Label in view, I need that Label's view in my ViewModel. I am using Dependency Service to set focus on Controls for Accessibility service, DS requires view as a param.
This is my Label
<Label
AutomationProperties.IsInAccessibleTree="{Binding ShowNoResults}"
IsVisible="{Binding ShowNoResults}"
Text="{Binding ResultsHeader}"/>
I tried Command but Label doesn't support command. Below code also not working
var view = GetView() as HomeworkView;
I am getting view always null. How can I fix this?
I am not quite sure what are you trying to achieve, but you can't access the View elements from you view model.
If you want to do something with the control, you can use the messaging center to do it, here is an example
in your ViewModel
MessagingCenter.Send(this, "your message here");
then in your page, you need to subscribe to this message from that view model and do the desired action
MessagingCenter.Instance.Unsubscribe<ViewModelClassNamedel>(this, "your message here");
MessagingCenter.Instance.Subscribe<ViewModelClassName>(this, "your message here", (data) =>
{
this.youControlName.Focus();
});
More detail added to Mohammad's answer.
Message Center doc.
In your ViewModel (with class name "YourViewModel"):
// Here we use control name directly.
// OR could make an "enum" with a value for each control.
string controlName = ...;
MessagingCenter.Send<YourViewModel>(this, "focus", controlName);
then in your page, subscribe to this message and do the desired action
.xaml.cs:
protected override void OnAppearing() {
{
base.OnAppearing();
// Unsubscribe before Subscribe ensures you don't Subscribe twice, if the page is shown again.
MessagingCenter.Instance.Unsubscribe<YourViewModel>(this, "focus");
MessagingCenter.Instance.Subscribe<YourViewModel>(this, "focus", (controlName) =>
{
View v = null;
switch (controlName) {
case "name1":
v = this.name1;
break;
case "name2":
v = this.name2;
break;
}
if (v != null) {
//v.Focus();
// Tell VM to use v as view.
((YourViewModel)BindingContext).SetFocus(v);
}
});
}
protected override void OnDisappearing() {
MessagingCenter.Instance.Unsubscribe<YourViewModel>(this, "focus");
base.OnDisappearing();
}
If need to pass View v back to VM, because that has the logic to use it:
public class YourViewModel
{
public void SetFocus(View view)
{
... your code that needs label's view ...
}
}
Not tested. Might need some slight changes. Might need
...(this, "focus", (sender, controlName) =>
instead of
...(this, "focus", (controlName) =>
UPDATE
Simple approach, if there is only ONE View that is needed in VM.
public class YourViewModel
{
public View ViewToFocus { get; set; }
// The method that needs ViewToFocus.
void SomeMethod()
{
...
if (ViewToFocus != null)
... do something with it ...
}
}
public class YourView
{
public YourView()
{
InitializeComponent();
...
// After BindingContext is set.
((YourViewModel)BindingContext).ViewToFocus = this.yourLabelThatShouldBeFocused;
}
}
ALTERNATIVE: It might be cleaner/more robust to set ViewToFocus in page's OnAppearing, and clear it in OnDisappearing. This ensures it is never used while the page is not visible (or in some delayed action after the page has gone away). I would probably do it this way.
protected override void OnAppearing()
{
base.OnAppearing();
((YourViewModel)BindingContext).ViewToFocus = this.yourLabelThatShouldBeFocused;
}
protected override void OnDisappearing()
{
((YourViewModel)BindingContext).ViewToFocus = null;
base.OnDisappearing();
}
When I click on an AjaxLink, I would like to have a validation via JavaScript on the client side first (because the LocalStorage is queried) and then depending on the result, further JavaScript calls are made. How can i achieve this?
In a pseudo code it would look like this:
new AjaxLink<>("myId", myModel) {
#Override
public void onClick(AjaxRequestTarget target) {
boolean isCounterValid = target.appendJavaScript(checkCounter()); // i know that this is not possible, therefore pseudo code
if(isCounterValid) {
target.appendJavaScript(someOtherJavaScript());
}
else {
target.appendJavaScript(anotherJavaScript());
}
}
private String checkCounter() {
return "var count = window.localStorage.getItem('myCounter'); return count !== 1;";
}
private String someOtherJavaScript() {
return "change something";
}
private String anotherJavaScript() {
return "change other thing";
}
};
You need to send extra request parameters with the Ajax call when the link is clicked. For that you should override updateAjaxAttributes(AjaxRequestAttributes attributes) method of AjaxLink:
#Override
protected void updateAjaxAttributes(AjaxRequestAttributes attributes)
{
attributes.getDynamicExtraParameters().add("var count = window.localStorage.getItem('myCounter'); return [{\"name\":\"count\", \"value\": count}]");
}
This way inside AjaxLink#onClick() you can read the count via:
int count = getRequest().getRequestParameters().getParameterValue("count").toInt();
AJAX components and behaviors can customize AJAX attributes overriding updateAjaxAttributes and using a custom implementation of AjaxCallListener which exposes different method to hook into the AJAX request cycle. In you case you could use AjaxCallListener#getBeforeSendHandler.
For a full introduction to this topic (with examples) see user guide:
https://ci.apache.org/projects/wicket/guide/8.x/single.html#_ajax_request_attributes_and_call_listeners
I have a form with many input-fields and need to handle a change to any of those input-fields; so I add a AjaxEventBehavior to the form, like:
Form<MyX> myForm = new Form<>("X", getModel());
myForm.add(new AjaxEventBehavior("onchange") {
#Override
protected void onEvent(AjaxRequestTarget target) {
handleFormChange(...);
}
});
The method handleFormChange gets called everytime I change some content in the input-fields of the form. But the model is not getting updated with the new value of the changed input-field of the form.
How can I get thoose model-updates? I tried AjaxFormComponentUpdatingBehavior. It updates the model, but I cannot use it for forms, just for FormComponents.
Does anybody has an ideas how to handle that? TIA!
With AjaxFormSubmitBehavior you can submit the whole form on each change.
First for on change use the dedicated OnChangeAjaxBehavior.
Then you can use the Iterator of the form to get all children and add then add the OnChangeAjaxBehavior to all FormComponents which will call your handleFormChange() on every change like this:
for (Iterator it = form.iterator(); it.hasNext();) {
Object o = it.next();
if (o instanceof FormComponent) {
((FormComponent) o).add(new OnChangeAjaxBehavior() {
#Override
protected void onUpdate(AjaxRequestTarget target) {
handleFormChange(...);
}
});
}
}
i'm trying to wrap my head around how to enterprise up my code: taking a simple routine and splitting it up into 5 or 6 methods in 3 or 4 classes.
i quickly came up three simple examples of code how i currently write it. Could someone please convert these into an MVC/MVP obfuscated version?
Example 1: The last name is mandatory. Color the text box red if nothing is entered. Color it green if stuff is entered:
private void txtLastname_TextChanged(object sender, EventArgs e)
{
//Lastname mandatory.
//Color pinkish if nothing entered. Greenish if entered.
if (txtLastname.Text.Trim() == "")
{
//Lastname is required, color pinkish
txtLastname.BackColor = ControlBad;
}
else
{
//Lastname entered, remove the coloring
txtLastname.BackColor = ControlGood;
}
}
Example 2: The first name is optional, but try to get it. We'll add a bluish tint to this "try to get" field:
private void txtFirstname_TextChanged(object sender, EventArgs e)
{
//Firstname can be blank.
//Hint them that they should *try* to get it with a bluish color.
//If they do enter stuff: it better be not all spaces.
if (txtFirstname.Text == "")
{
//Nothing there, hint it blue
txtFirstname.BackColor = ControlRequired;
}
else if (txtFirstname.Text.Trim() == "")
{
//They entered spaces - bad user!
txtFirstname.BackColor = ControlBad;
}
else
{
//Entered stuff, remove coloring
txtFirstname.BackColor = SystemColors.Window;
}
}
Example 3 The age is totally optional. If an age is entered, it better be valid:
private void txtAge_TextChanged(object sender, EventArgs e)
{
//Age is optional, but if entered it better be valid
int nAge = 0;
if (Int32.TryParse(txtAge.Text, out nAge))
{
//Valid integer entered
if (nAge < 0)
{
//Negative age? i don't think so
txtAge.BackColor = ControlBad;
}
else
{
//Valid age entered, remove coloring
txtAge.BackColor = SystemColors.Window;
}
}
else
{
//Whatever is in there: it's *not* a valid integer,
if (txtAge.Text == "")
{
//Blank is okay
txtAge.BackColor = SystemColors.Window;
}
else
{
//Not a valid age, bad user
txtAge.BackColor = ControlBad;
}
}
}
Every time i see MVC code, it looks almost like random splitting of code into different methods, classes, and files. i've not been able to determine a reason or pattern to their madness. Without any understanding of they why it's being one some way, it makes no sense. And using the words model, view, controller and presenter, like i'm supposed to know what that means, doesn't help.
The model is your data.
The view shows data on screen.
The controller is used to carry out
the users actions
And oranges taste orangy.
Here's my attempt at splitting things up in order to make the code more difficult to follow. Is this anywhere close to MVC?
private void txtFirstname_TextChanged(object sender, EventArgs e)
{
FirstnameTextChangedHandler(sender, e);
}
private void FirstnameTextChangedHandler(sender, e)
{
string firstname = GetFirstname();
Color firstnameTextBoxColor = GetFirstnameTextBoxColor(firstname);
SetFirstNameTextBoxColor(firstnameTextBoxColor);
}
private string GetFirstname()
{
return txtFirstname.Text;
}
private Color GetFirstnameTextBoxColor(string firstname)
{
//Firstname can be blank.
//Hint them that they should *try* to get it with a bluish color.
//If they do enter stuff: it better be not all spaces.
if (firstname == "")
{
//Nothing there, hint it blue
return GetControlRequiredColor();
}
else if (firstname.Trim() == "")
{
//They entered spaces - bad user!
return GetControlBadColor();
}
else
{
//Entered stuff, remove coloring
return GetControlDefaultColor();
}
}
private Color GetControlRequiredColor()
{
return ControlRequired;
}
private Color GetControlBadColor()
{
return ControlBad;
}
private Color GetControlGoodColor()
{
return ControlGood;
}
//am i doin it rite
i've obfuscated the code, but it's still altogether. The next step in the MVC obfuscation, i gather, is to hide the code in 3 or 4 different files.
It's that next step that i don't understand. What is the logical separation of which functions are moved into what other classes? Can someone translate my 3 simple examples above into full fledged MVC obfuscation?
Edit: Not ASP/ASP.NET/Online. Pretend it's on a desktop, handheld, surface, kiosk. And pretend it's language agnostic.
The purpose of MVC/MVP patterns is not obfuscation, but separation of concerns. Obfuscation is to (conceal the) intended meaning in communication, making communication confusing, intentionally ambiguous, and more difficult to interpret: ref. The use of patterns is to make the code cleaner and more understandable. I suggest you start out by reading the wikipedia entries on MVC and MVP.
Both patterns are ways of structuring your code so that your application is broken up into elements that carry out specific purposes that have clearly defined interaction boundaries. Rather than having code that specifically addresses business concerns, input/output handling, and presentation throughout the various classes of the application, these concerns are separated and isolated in the various architectural components. These architectural elements are insulated from one another by the interaction boundaries (interfaces) making them more independent of one another and easier to modify without affect the application as a whole.
The main idea I have when implementing MVC for Windows Forms is that I want to have unit tests for my model and my controller. In order to achieve that, my controller should not know anything about the views using it, and so any notifications that should be handled on UI level are implemented as events. In your example, my controller would look something like this:
class Controller
{
// This is the model we are operating on
private Model model_;
public enum Status
{
Normal,
Required,
Good,
Bad
}
public delegate void FirstNameStatusChangedDelegate(Status newStatus);
public event FirstNameStatusChangedDelegate FirstNameStatusChangedEvent;
public string FirstName
{
get { return model_.FirstName; }
set
{
if (value == "")
RaiseFirstNameStatusChanged(Status.Required);
else if ( value.Trim() == "" )
RaiseFirstNameStatusChanged(Status.Bad);
else
{
model_.FirstName = value;
RaiseFirstNameStatusChanged(Status.Normal);
}
}
}
private void RaiseFirstNameStatusChanged(Status newStatus)
{
if ( FirstNameStatusChangedEvent != null )
FirstNameStatusChangedEvent(newStatus);
}
}
And the view would provide handlers for the FirstNameStatusChanged event:
class View : Form
{
private Controller controller_;
private static readonly Dictionary<Controller.Status, Color> statusColors_ = new Dictionary<Controller.Status, Color>
{
{Controller.Status.Normal, SystemColors.Window},
{Controller.Status.Required, ControlRequired},
{Controller.Status.Good, ControlGood},
{Controller.Status.Bad, ControlRed}
};
public View(Controller controller)
{
InitializeComponent();
controller_ = controller;
contoller_.FirstNameStatusChangedEvent += OnFirstNameStatusChanged;
}
private void txtFirstname_TextChanged(object sender, EventArgs e)
{ controller_.FirstName = txtFirstName.Text; }
private void OnFirstNameStatusChanged(Controller.Status newStatus)
{ txtFirstName.BackColor = statusColors_[newStatus]; }
}
Most of what you doing in your code belongs to the Controller class since it describes the the logic. Your View should just describe UI and give easy access to UI components. Model class should describe your data model.
The idea is simple: Controller does everything, but it has to know about the View and the Model. For example as View is initialized, Controller sets up all the logic ( kinda what you already doing). As Model is assigned to the Controller - it sets the values into appropriate UI controls and does the same to retrieve data and return is as Model.
So basically you give your data model class to the controller, it does the editing and returns your data as model class again.
It would be very hard to follow MVC in classic ASP.NET if possible, so I will reply based on MVP.
On your first example, you are trying to do a validation. Validating a surname is the responsibility of Presenter. Showing the field red is the responsibility of View. So, your view class would be like this:
private void Page_Load()
{
this._presenter = new Presenter();
}
private void txtLastname_TextChanged(object sender, EventArgs e)
{
txtLastName.BackColor = presenter.IsLastnameValid(txtLastName.Text) ?
ControlGood : ControlBad;
}
And your presenter class would be something like this:
public Presenter()
{
public bool IsLastNameValid(string lastname)
{
return string.IsNullOrEmpty(lastname);
}
}
Last name is your model here.
Please note that I prepared this classes only for showing how would you form an MVP structure. In real world, there are lots of better ways to do validation. Normally you would use this approach for your business instead of validation.
Ian,
If you want the controls to validate immediately, you need to use javascript or jQuery. This is also true for classic ASP.NET. Since you are using Code Behind methods, I assume that your validation waits for a postback.
The following examples are from the NerdDinner project. NerdDinner is an open source project that serves as an example of ASP.NET MVC architecture. The authors have graciously provided a tutorial with it, available at http://nerddinnerbook.s3.amazonaws.com/Intro.htm
When a form is submitted in ASP.NET MVC, it enters the corresponding controller as a FormCollection object:
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(int id, FormCollection formValues) {
Dinner dinner = dinnerRepository.GetDinner(id);
try
{
UpdateModel(dinner);
dinnerRepository.Save();
}
catch
{
ModelState.AddModelErrors(dinner.GetRuleViolations())
}
return RedirectToAction("Details", new { id = dinner.DinnerID });
}
UpdateModel takes the form values and attempts to stuff them into the dinner object. The dinner object looks like this:
public partial class Dinner {
public bool IsValid {
get { return (GetRuleViolations().Count() == 0); }
}
public IEnumerable<RuleViolation> GetRuleViolations() {
yield break;
}
public IEnumerable<RuleViolation> GetRuleViolations() {
if (String.IsNullOrEmpty(Title))
yield return new RuleViolation("Title is required", "Title");
if (String.IsNullOrEmpty(Description))
yield return new RuleViolation("Description is required", "Description");
if (String.IsNullOrEmpty(HostedBy))
yield return new RuleViolation("HostedBy is required", "HostedBy");
if (String.IsNullOrEmpty(Address))
yield return new RuleViolation("Address is required", "Address");
if (String.IsNullOrEmpty(Country))
yield return new RuleViolation("Country is required", "Address");
if (String.IsNullOrEmpty(ContactPhone))
yield return new RuleViolation("Phone# is required", "ContactPhone");
if (!PhoneValidator.IsValidNumber(ContactPhone, Country))
yield return new RuleViolation("Phone# does not match country", "ContactPhone");
yield break;
}
partial void OnValidate(ChangeAction action) {
if (!IsValid)
throw new ApplicationException("Rule violations prevent saving");
}
}
Notice the IsValid method and the RuleViolations enumerator. If everything is set up properly, all you have to do is define your validations in here, and ASP.NET MVC will take care of the rest for you.
The final validated result looks like this:
I encourage you to get the NerdDinner application and tutorial at http://nerddinner.codeplex.com/
I want to re-write a method that has way too many nested if statements.
I came up with this approach and wanted your opinions:
public void MyMethod()
{
bool hasFailed = false;
try
{
GetNewOrders(out hasFailed);
if(!hasFailed)
CheckInventory(out hasFailed);
if(!hasFailed)
PreOrder(out hasFailed);
// etc
}
catch(Exception ex)
{
}
finally
{
if(hasFailed)
{
// do something
}
}
}
I've done stuff similar to that, but without the exception handling:
BOOL ok = CallSomeFunction();
if( ok ) ok = CallSomeOtherFunction();
if( ok ) ok = CallYetAnotherFunction();
if( ok ) ok = WowThatsALotOfFunctions();
if( !ok ) {
// handle failure
}
Or if you want to be clever:
BOOL ok = CallSomeFunction();
ok &= CallSomeOtherFunction();
ok &= CallYetAnotherFunction();
...
If you are using exceptions anyway, why do you need the hasFailed variable?
Not really. Your methods should raise an exception in case of an error to be caught by your "catch" block.
As far as I can see this is an example of cascade steps where second and third one will be executed if first and first and second are valid, i.e. return hasFailed==false.
This code can be made much more elegant using Template Method and Decorator design pattern.
You need one interface, concrete implementation, abstract class and several subclasses of the abstract class.
public interface Validator {
public boolean isValid();
}
public class GetNewOrders implements Validator {
public boolean isValid() {
// same code as your GetNewOrders method
}
}
public abstract class AbstractValidator implements Validator {
private final Validator validator;
public AbstractValidator(Validator validator) {
this.validator = validator;
}
protected boolean predicate();
protected boolean isInvalid();
public final boolean isValid() {
if (!this.validator.isValid() && predicate() && isInvalid())
return false;
return true;
}
}
public class CheckInventory extends AbstractValidator {
public CheckInventory(Validator validator) {
super(validator);
}
#Override
public boolean predicate() {
return true;
}
#Override
public boolean isInvalid() {
// same code as your CheckInventory method
}
}
public class PreOrder extends AbstractValidator {
public CheckInventory(Validator validator) {
super(validator);
}
#Override
public boolean predicate() {
return true;
}
#Override
public boolean isInvalid() {
// same code as your PreOrder method
}
}
Now your method can look much more elegant:
public void MyMethod() {
bool success = false;
try {
Validator validator = new GetNewOrders();
validator = new CheckInventory(validator);
validator = new PreOrder(validator);
success = validator.isValid();
} finally {
if (!success) {
// do something
}
}
}
Validator object can be created in one line, but I prefer this style since it makes obvious the order of validation. Creating new validation link in the chain is matter of subclassing AbstractValidator class and implementation of predicate and isInvalid methods.
Without commenting on the try/catch stuff since I really don't know what is going on there, I would change it so the called methods return true/false for success and then just check them depending on the boolean short-circuiting to avoid calling later methods if the preceding method failed.
public void MyMethod()
{
bool success = false;
try
{
success = GetNewOrders()
&& CheckInventory()
&& PreOrder();
// etc
}
catch(Exception ex) { }
finally
{
if(!success)
{
}
}
}
This doesn't really look good to me. The use of the hasFailed variable is really not nice. if GetNewOrders fails with an exception, you for instance end up inside the catch block with hasFailed = false !
Opposed to other answers here I believe there MAY be legitimate uses for boolean "hasFailed" that are not exceptional. But I really don't think you should mix such a condition into your exception handler.
I know I'll probably duplicate a few posts: What's wrong with else? You could also use lazy evaluation (a() && b()) to link methods - but that relies on status being given as return value, which is more readable anyhow IMHO.
I don't agree with posters that you should raise an exception, because exceptions should be raised if program faults occur or the program enters an exceptional state because of operations. Exceptions are not business logic.
I would do it like this:
public void MyMethod()
{
bool success = false;
try
{
GetNewOrders(); // throw GetNewOrdersFailedException
CheckInventory(); // throw CheckInventoryFailedException
PreOrder(); // throw PreOrderFailedException
success = true;
}
catch( GetNewOrdersFailedException e)
{
// Fix it or rollback
}
catch( CheckInventoryFailedException e)
{
// Fix it or rollback
}
catch( PreOrderFailedException e)
{
// Fix it or rollback
}
finally
{
//release resources;
}
}
Extending an exception is rather trivial,
public NewExecption : BaseExceptionType {}
Well, I don't like code that appears to get a list of orders and then process them, and then stop processing them when an error occurs, when surely it should skip that order and move to the next? The only thing to completely fail on is when the database (source of orders, destination of preorders) dies. I think that the entire logic is a bit funky really, but maybe that's because I don't have experience in the language you are using.
try {
// Get all of the orders here
// Either in bulk, or just a list of the new order ids that you'll call the DB
// each time for, i'll use the former for clarity.
List<Order> orders = getNewOrders();
// If no new orders, we will cry a little and look for a new job
if (orders != null && orders.size() > 0) {
for (Order o : orders) {
try {
for (OrderItem i : o.getOrderItems()) {
if (checkInventory(i)) {
// Reserve that item for this order
preOrder(o, i);
} else {
// Out of stock, call the magic out of stock function
failOrderItem(o, i);
}
}
} catch (OrderProcessingException ope) {
// log error and flag this order as requiring attention and
// other things relating to order processing errors that aren't database related
}
}
} else {
shedTears();
}
} catch (SQLException e) {
// Database Error, log and flag to developers for investigation
}
Your new approach is not that bad for a simple set of instructions, but what happens when additional steps are added? Do you / would you ever require transactional behavior? (What if PreOrder fails? or If the next step after PreOrder fails?)
Looking forward, I would use the command pattern:
http://en.wikipedia.org/wiki/Command_pattern
...and encapsulate each action as a concrete command implementing Execute() and Undo().
Then it's just a matter of creating a queue of commands and looping until failure or an empty queue. If any step fails, then simply stop and execute Undo() in order on the previous commands. Easy.
Chris solution is the most correct. But I think you should not do more than you need. Solution should be extandable and that's enough.
Change value of a parameter is a bad practice.
Never use empty generic catch statement, at least add a comment why you do so.
Make the methods throw exception and handle them where it is appropriate to do so.
So now it is much more elegant :)
public void MyMethod()
{
try
{
GetNewOrders();
CheckInventory();
PreOrder();
// etc
}
finally
{
// do something
}
}