Is there a way to get a collection of all the components contained in a Layout in Vaadin 8?
I have a GridLayout with a bunch of TextField objects. I'd like to set all of them to have 100% width. Rather than hand-code each explicitly, I'd rather write a soft-coded loop that looks through all the widgets in the layout.
All Layouts in Vaadin 8, that can host multiple components (like GridLayout) implement HasComponents Interface
https://vaadin.com/download/release/8.4/8.4.4/docs/api/com/vaadin/ui/HasComponents.html
The interface defines Iterator, which can be used to go thru the components in the layout. I think it fits perfectly your purpose.
Since Java 8 is supported, Iterable supports also forEach(..).
Related
I'm developing an Xamarin Android Mvx5-beta application. When running on a small-screen device, I want to show a drawer navigation using the Toolbar and the hamburger-icon. On larger devices, e.g. tablets, I want a different layout conaining three columns. No drawer navigation but a static panel with navigation options and two other panels for content.
I started with the examples XPlatformMenus and Fragments to get a drawer navigation layout combined with the use of activities (with fragments) in different layouts qualifiers, like:
Question:
Using this approach, Android automaticly looks for an activity with the same name (e.g. main_activity.axml) in the appropriate layout-qualifier folders. But on the larger screens I don't need a drawer layout and I do need an extra column. The Mvx-viewmodel does not yet know what layout to render, so it just calls:
ShowViewModel<HomeViewModel>();
ShowViewModel<MenuViewModel>();
These ViewModels, for example MenuViewModel, are registered for fragments that require a navigation_frame, as shown in here:
[MvxFragment(typeof(MainViewModel), Resource.Id.navigation_frame)]
[Register("mydemoapp.droid.views.fragments.MenuFragment")]
public class MenuFragment : MvxFragment<MenuViewModel>, NavigationView.IOnNavigationItemSelectedListener
{
<..>
}
So, rendering this same Activity in layout-sw600dp requires a navigation_frame. Which I don't want on these larger displays.
What would be the preferred design choise in this situation? I can think of two:
Show/hide elements in the Activity programmatically by querying the screen info
Don't make use of layout qualifiers, but design complete seperate Activities for larger screens and based on screen size let MVX Show ViewModel-A or ViewModel-B.
Any advice would be appreciated, many thanks in advance.
I think it depends how different your layout need to be between large screen and small screen form factors.
Few UI differences
In addition to using different layouts, you can define a bool property in your XML values resources that is different between standard and sw-600dp
values
<bool name="is_large_screen">false</bool>
values-sw600dp
<bool name="is_large_screen">true</bool>
You can then read this value in your Android views and prevent methods like ShowViewModel<MenuViewModel>(); firing when on large screens by altering the method calls from the view.
Many differences/Structural differences
If they share the same business logic but have very different UI requirements and you want to keep large screen code separate. Then I would suggest sharing the ViewModels but creating two separate Activites and layouts to handle the UI presentation. Using this method requires a bit more setup as you have to override some default MvvmCross behaviors as by default you can not register multiple Activities/Fragments to the same ViewModel. Overriding the MvxViewModelViewTypeFinder view lookup FindTypeOrNull you can intercept the lookup and filter types base on naming conventions. For example all large screen views end with "Tablet". Using the is_large_screen bool you can flag which views to register.
I'm looking for a way to make a dataGrid provided by richfaces responsive.
Meaning, the grid scales based on the size of the device screen.
I've taken a look at Richfaces Bootstrap : http://planet.jboss.org/post/richfaces_bootstrap
but they recommend not to use it in any production code since it is still under development. Tags and attributes are subject to change at anytime.
You'll need to overwrite the default CSS. Here is the list of classes that make up a dataGrid.
The responsivness is achieved by queries like this:
#media(min-width:768px) and (max-width:979px) {
/* styles for the given width range */
}
You shouldn't use the Bootstrap components but you can use the CSS. However the dataGrid is a table and those don't scale very well.
Swing had LayoutManager's separate from the containers. So far as I can tell, JavaFX doesn't do that.
I have a complex structure of nodes that I want the user to be able to toggle between several different layout approaches. Something equivalent to the user specifying flow and all containers are converted to the equivalent of FlowPanes. Then they could choose vertical and everything is laid out vertically.
Is there a way to do this other than swapping out the nodes/recreating the whole structure?
I should note: the hierarchy changes at runtime and it is deeply nested.
I mention Swing because this is straightforward to do in Swing by maintaining a list of all containers in the entire hierarchy, and with a simple loop (or tree traversal without the list) setting a new LayoutManager on them. JavaFX doesn't seem to have this possibility because the layout behavior appears to be internal to the nodes.
Isn't something like this working ?
AnchorPane main=new AnchorPane();
AnchorPane sub1=new AnchorPane();
sub1.getChildren().add(btn);
main.getChildren().add(sub1);
When you want to switch the layout
AnchorPane sub2=new AnchorPane();
main.getChildren().remove(sub1);
main.getChildren().add(sub2);
Edit
I guess I missed how you are doing layouts. This is how I envisioned it.
Definitions to Various Components
MainLayout
-> CustomLayout 1
-> References to various components. ( Essentially you are not creating all the components for every layout, rather you are referring to them in each layout )
-> CustomLayout 2
-> References to various components. ( More or less a different arrangement of the same components, adds some component references and removes some )
-> CustomLayout 3
-> References to various components.
Making a bold statement, but if there were a tool in JavaFX, how would it do this automatically ? Each template needs to know where it should render a particular component and arguably the easiest way to do this is just create a new template that arranges the components in a different layout and swap the template when user wants to see a different layout.
This is not easy to do in Swing. You would still need to set all the layout constraints on the individual components again, unless your layout is very straightforward.
I don't see how there is much difference in this between swing and javaFX. In JavaFX you would need to add the same controls to a different container (VBox, HBox etc.) but you still don't need to recreate the controls every time. It is a little awkward to find the containers in the middle of the node hierarchy but I'm sure there is some kind of elegant recursive solution :)
I do have a custom layout with some controls written in an XML layout file.
a class is attached to this layout like
<com.project.layout ...>
<Checkbox...1
<TextView...2
<Button ...3
<ImageView..4 ...
../>
depending on the user interaction i would like to display only 3 of the defined controls like 1,2,3. With a click from the user i'd like to have 1,2,4
To do so, i developed some state classes that handle the removeView and addView.
I have some issues about this as:
1/ When can i be sure everything is created and i can interact with the UI (onLayout() & onMeasure() seem to happen everytime a control is processed)
2/ it seems that since i defined the layout with the 4 controls, even thought i write removeView, the space used by the removed control is not used by the other controls... is there a way i can ask the layout to reorder it display?
I found out , it turns out it was easy actually, there is a method i have to override called onFinishInflate().
One major difference that I have noticed between ExtJS 3.x and 4.x is how the rendering/layout calculation is handled for components that are rendered inside of a containing element that has display:none (NOT an Ext created/monitored containing element). In 3.x, upon showing the containing element, the Ext component it contained would be properly rendered and sized to whatever dimensions i set for it.
However, in 4.x, that same component will not be displayed at all and have a zero height and width when its containing element was shown. After it was visible if I do a call to .setSize() it would then properly be displayed. Problem is, in my application there is just no way to be able to go through all the events that could cause a hidden component to be shown, and add code to make sure its layout is manually forced to be recalculated.
So my question is, is there any way to get back 3.x's behavior in this situation for all components across the board in 4.x?
What you can try to do is set up listeners on your components that delegate to the underlying DOM elements, perhaps that will solve your issue.
However my suggestion is if at all possible is to use the framework to manage the entire page layout using Viewport. You can still suck in the HTML (if you must) and render it inside containers or panels for example. Perfect use case here is Header and Footer which are generated by server side code (jsp, gsp, asp..) and then displayed in the North or South regions of the Viewport using contentEl : 'myDivId' configuration.