I have a view in the Views folder and I have a class library project. In this project I want to render view to string.
public class DumpService
{
public void Method()
{
var renderedView = SomeMethodForRenderingView();
}
}
I have found some answers, but there are used controller context which I don't have in the class library project.
How can I do this?
You need to read the view text - just open it with and read the text, and then parse it with :
Razor.Parse
Related
Using Vaadin 14.0.13 without compatibility mode.
I use a view to create a Dialog with dynamic content:
#Route("")
public class MainView extends VerticalLayout {
public MainView(DialogContentProvider contentProvider) {
this.add(new Button("Click me!", event -> new Dialog(contentProvider.create()).open()));
}
}
The contentProvider is an interface
public interface DialogContentProvider {
Component create();
}
with this implementation:
public class CheckBoxContentProvider implements DialogContentProvider {
#Override
public Component create() {
return new Checkbox("My checkbox", true);
}
}
instantiated by Spring Boot (version 2.2.1.RELEASE) with a bean:
#Bean
public DialogContentProvider contentProvier() {
return new CheckBoxContentProvider();
}
When I click on the button, the dialog is opened but the checkbox haven't the box:
The source code is on github: https://github.com/gronono/bug-vaadin-checkbox
I don't understand why and how I can fix it. If I include the checkbox creation inside the main view, it works fine:
#Route("")
public class MainView extends VerticalLayout {
public MainView(DialogContentProvider contentProvider) {
// this.add(new Button("Click me!", event -> new Dialog(contentProvider.create()).open()));
this.add(new Button("Click me!", event -> new Dialog(new Checkbox("My checkbox", true)).open()));
}
}
This sound an awful lot like this (related github issue)
Basically, this happens when you don't have any View that uses a Checkbox directly, but through other means like reflection or in your case the contentProvider, because in no view of your app there is any import statement of Checkbox (--> therefore, vaadins scan during the installation will not detect usages of Checkbox, so it will not download npm stuff for checkbox).
in the github it says this will be fixed in 14.1
If you need a fix now, for me it worked when I declared a field of that type in any view with a #Route. That field doesn't have to be used.
#Route("")
public class MainView extends VerticalLayout {
private Checkbox unusedCheckbox; // this line fixes it.
public MainView(DialogContentProvider contentProvider) {
this.add(new Button("Click me!", event -> new Dialog(contentProvider.create()).open()));
}
}
Addendum: This is not related to the Checkbox component specifically, it happens with any vaadin component that isn't initially scanned in a route, but used anyway through reflective-, provider-, or generic means.
Edit: You can also work around this currently by adding a #Route(registerAtStartup = false) to your provider that uses the Checkbox directly. This will make vaadins scan see the checkbox usage (therefore importing its npm package), but will not actually register the provider as a real route..
Another way which I prefer if you need this for multiple components is to create a new View with a #Route(registerAtStartup = false) which only defines private variables for each component that you'll need in the application (and arent already used directly in some view of yours). This has the advantage of all these component usage definitions in one place, and once the official fix is released, you need only to delete one class and the deprecated workaround is gone.
#Route(registerAtStartup = false)
public class ComponentImportView extends VerticalLayout {
private Checkbox checkBox;
private Upload upload;
private ProgressBar progressBar;
}
I‘m a beginer who uses MvvmCross for the Xamarin.Android.I try to realize the function like 'click the button and show a dialog to say hello'.
When I use the way which sets ViewModel object to Activity object's DataContext to bind,I can pass UI object directly (or using Interface indirectly).In this way,I can access UI object to show a dialog.
In another way likes the offical demo, bing the UI object and ViewModel automatically,how can I show the dialog?The auto bing code like this
public class App:MvxApplication { public App() { Mvx.RegisterSingleton(new MvxAppStart()); } }
[Activity(Label = "MvvmC_TutorialActivity")] public class MvvmC_TutorialActivity : MvxActivity
{
.............
}
Thanks！
I slove the problem!I can pass the UI object in 'MvxActivity's OnViewModelSet'.
protected override void OnViewModelSet()
{
SetContentView(Resource.Layout.View_Tip);//pass UI object here
}
In my Xamarin.iOS application there are many buttons with the same scheme but different from to standart UIButton. I created one class for the buttons because most of the features are same but for example the textcolor or the backgroundcolor are different.
So how can I put an extra information about any button in the storyboard?
And how can I react on it in code?
You can make your custom element visible in for the designer with the DesignTimeVisible and the Register Attribute like
[Register ("CustomButton"), DesignTimeVisible (true)]
public class CustomButton: UIButton {
[Export ("CustomProperty "), Browsable (true)]
public int CustomProperty {get; set;}
public CustomButton(IntPtr handle) : base (handle) { }
public CustomButton()
{
// Called when created from code.
Initialize ();
}
public override void AwakeFromNib ()
{
// Called when loaded from xib or storyboard.
Initialize ();
}
void Initialize ()
{
// Common initialization code here.
CustomProperty = 0xB00B5;
}
}
For all properties that you want to set in the Designer you just hae to add Export and Browsable (true). In the Initializeyou can set all the vlaues of the common properties.
It will appear in the Toolbox under Custom Components. You might have to rebuild.
And the Custom Property can be modified in the Properties pane
More info: https://developer.xamarin.com/guides/ios/user_interface/designer/ios_designable_controls_overview/
I have a Vaadin Navigator with multiple View elements. Each view has a different purpose however some also contain common traits that I have put inside custom components.
One of those custom components is the menu - it is positioned at the top and allows navigation between the different views. I create and add this component inside the constructor of each view (if you are interested in the menu's implementation see the end of this post). Here is a skeleton for each custom view:
class MyViewX implements View {
MenuViewComponent mvc;
public MyViewX() {
mvc = new MenuViewComponent();
addComponent(mvc);
}
#Override
public void enter(ViewChangeEvent event) {
}
}
So far, so good. In order to make things simple I will explain my problem using a simple label and not one of my other custom components but the dependency that I will describe here is the same for those components just like with the label.
Let's say I have a label which sole purpose is to display a greeting with the user's username. In order to do that I use VaadinSession where I store the attribute. This is done by my LoginController, which validates the user by looking into a database and if the user is present, the attribute is set and one of the views is opened automatically. The problem is that VaadinSession.getCurrent().getAttribute("username") returns null when called inside the constructor. This of course makes sense omho because a constructor should not be bound by a session-attribute.
So far I have managed to use the enter() method where there is no problem in retrieving session attributes:
class MyViewX implements View {
MenuViewComponent mvc;
public MyViewX() {
mvc = new MenuViewComponent();
addComponent(mvc);
}
#Override
public void enter(ViewChangeEvent event) {
String username = (String)VaadinSession.getCurrent().getAttribute("username");
Label greeting = new Label("Hello " + username);
addComponent(greeting);
}
}
The issue that comes from this is obvious - whenever I open the view where this label is present, a new label is added so if I re-visit the view 10 times, I will get 10 labels. Even if I move the label to be a class member variable the addComponent(...) is the one that screws things up. Some of my custom components really depend on the username attribute (in order to display user-specific content) hence I also have to place those in the enter(...) method. The addComponent(...) makes a mess out of it. I even tried the dirty way of removing a component and then re-adding it alas! in vain:
class MyViewX implements View {
MenuViewComponent mvc;
Label greeting;
public MyViewX() {
mvc = new MenuViewComponent();
addComponent(mvc);
}
#Override
public void enter(ViewChangeEvent event) {
String username = (String)VaadinSession.getCurrent().getAttribute("username");
greeting = new Label("Hello " + username);
// Remove if present
try { removeComponent(greeting); }
catch(Exception ex) { }
// Add again but with new content
addComponent(greeting);
}
}
but it's still not working. So my question is: what is the simplest way of updating a component that requires session-bound attributes?
The navigation via the menu custom component is omho not the issue here since all components of the menu are loaded in it's constructor. That's why it's also load that component in particular in a view's own constructor. Here is an example of a button in my menu that opens a view:
#SuppressWarnings("serial")
#PreserveOnRefresh
public class MenuViewComponent extends CustomComponent {
public MenuViewComponent(boolean adminMode) {
HorizontalLayout layout = new HorizontalLayout();
Label title = new Label("<h2><b>Vaadin Research Project</b></h2>");
title.setContentMode(ContentMode.HTML);
layout.addComponent(title);
layout.setComponentAlignment(title, Alignment.TOP_LEFT);
Button personalDashboardButton = new Button("Personal dashboard", new Button.ClickListener() {
#Override
public void buttonClick(ClickEvent event) {
getUI().getNavigator().navigateTo(MainController.PERSONALDASHBOARDVIEW);
}
});
personalDashboardButton.setStyleName(BaseTheme.BUTTON_LINK);
layout.addComponent(personalDashboardButton);
layout.setComponentAlignment(personalDashboardButton, Alignment.TOP_CENTER);
// Add other buttons for other views
layout.setSizeUndefined();
layout.setSpacing(true);
setSizeUndefined();
setCompositionRoot(layout);
}
}
PERSONALDASHBOARDVIEW is just one of the many views I have.
It may be worth considering how long should your view instances "live", just as long they're displayed, until the session ends or a mix of the two. With this in mind and depending on what needs to happen when you enter/re-enter a view, you have at least the following 3 options:
1) Recreate the whole view (allowing for early view garbage-collection)
first register a ClassBasedViewProvider (instead of a StaticViewProvider) which does not hold references to the created views:
navigator = new Navigator(this, viewDisplay);
navigator.addProvider(new Navigator.ClassBasedViewProvider(MyView.NAME, MyView.class));
simple view implementation
public class MyView extends VerticalLayout implements View {
public static final String NAME = "myViewName";
#Override
public void enter(ViewChangeListener.ViewChangeEvent event) {
// initialize tables, charts and all the other cool stuff
addComponent(new SweetComponentWithLotsOfStuff());
}
}
2) Keep some already created components and replace others
public class MyView extends VerticalLayout implements View {
private MySweetComponentWithLotsOfStuff mySweetComponentWithLotsOfStuff;
public MyView() {
// initialize only critical stuff here or things that don't change on enter
addComponent(new MyNavigationBar());
}
#Override
public void enter(ViewChangeListener.ViewChangeEvent event) {
// oh, so the user does indeed want to see stuff. great, let's do some cleanup first
removeComponent(mySweetComponentWithLotsOfStuff);
// initialize tables, charts and all the other cool stuff
mySweetComponentWithLotsOfStuff = new SweetComponentWithLotsOfStuff();
// show it
addComponent(mySweetComponentWithLotsOfStuff);
}
}
3) Lazy creating and updating (or not) the content when entering
public class MyView extends VerticalLayout implements View {
private boolean isFirstDisplay = true;
private MySweetComponentWithLotsOfStuff mySweetComponentWithLotsOfStuff;
public MyView() {
// initialize only critical stuff here, as the user may not even see this view
}
#Override
public void enter(ViewChangeListener.ViewChangeEvent event) {
// oh, so the user does indeed want to see stuff
if (isFirstDisplay) {
isFirstDisplay = false;
// lazily initialize tables, charts and all the other cool stuff
mySweetComponentWithLotsOfStuff = new SweetComponentWithLotsOfStuff();
addComponent(mySweetComponentWithLotsOfStuff);
} else {
// maybe trigger component updates, or simply don't do anything
mySweetComponentWithLotsOfStuff.updateWhateverIsRequired();
}
}
}
I'm sure (and curious) that there may be other options, but I've mainly used a variation of 1) using spring with prototype views and component tabs.
I think I misunderstand something about MVC. I'm trying to do the following:
public class ControllerA : Controller
{
public ActionResult Index()
{
// do code
// perform action on ControllerB - something like:
// RedirectToAction("Action", "ControllerB");
// CARRY ON with more code
}
}
public class ControllerB : Controller
{
public void Action()
{
// do code
}
}
Obviously RedirectToAction("Action", "ControllerB"); isn't working. So how do I do it? I guess I could have all controllers that need to use Action() inherit from ControllerB but that feels a really bad way to do it. Please help!
You have to return the ActionResult from RedirectToAction()
return RedirectToAction("Action", "ControllerB");
is what you need to do if you want RedirectToAction to actually redirect to an action. After you clarified what "isn't working" means to you I think you should just have all controllers inherit from a base. That is a pretty standard approach.
public class ControllerA : ControllerB
{
public ActionResult Index()
{
// do code
Action();
// CARRY ON with more code
}
}
public class ControllerB : Controller
{
public void Action()
{
// do code
}
}
I believe the controller you are currently executing is an instance of the class so you would need to make an instance of controller B to be able to execute anything on it, so what you are trying to do there just won't really work without a hack.
I think however there is 2 methods to better get the results i think you are after:
1) Make a 'ControllerBase' class and have all controllers inherit from it instead of from 'Controller' then any shared code you can add into the base class (as a static method perhaps) and then all controllers can access it as a member nice and easy.
2) As MVC will make a straight up DLL you can add in new classes as you need, eg add a new project folder like 'Globals' add a new class file called 'Funcs' and there you have a static lib that you can access from anywhere, Funcs.SendEmail(); etc
If i'm off the mark ok! happy coding anyway heh
I have injected controllers with a factory method from the controller factory as a delegate (Func CreateController), and used that to create sub-controllers, such as in this circumstance. There's plenty of ways to accomplish your goal, but I think that might be quick way to get what you want working.