Are InputComponents and Dialogs incompatible? - dialog

Question

In the simple Dialog below:
// choice of layout has no impact:
Container cont=new Container(new TextModeLayout(3, 1));
//Container cont=new Container(new BoxLayout(BoxLayout.Y_AXIS));
TextComponent firstName=new TextComponent().label("First Name").text(person.firstname);
TextComponent lastName=new TextComponent().label("Last Name").text(person.lastname);
TextComponent cost=new TextComponent().label("Cost per Session").text(person.getCostString());
cost.getField().setConstraint(TextArea.DECIMAL);
// NOTE HERE
// doesn't work: // works:
cont.add(firstName); // cont.add(firstName.getField());
cont.add(lastName); // cont.add(lastName.getField());
cont.add(cost); // cont.add(cost.getField());
Dialog.show("Edit Client", cont, new Command(CANCEL), new Command(OK));
Nothing appears in the Dialog unless I add the TextField instead of the TextComponent to my container at the NOTE HERE comment. This means I lose the nice appearance of the labelled input fields (yes I know I could label them myself, but they wouldn't look as good on different devices). My choice of layout manager at the top does not affect this issue (I've tried several). I can't find evidence online to conclude there's an incompatibility here, adding TextComponents and other InputComponents works fine on a Form, just not in a Dialog.
I'm having the same problem in another Dialog that uses PickerComponents. The PickerComponent doesn't appear unless I add the Picker itself, and then the Picker spawned from a Dialog looks all wrong. I'm hoping the simpler code question above will answer this quandary as well.
It's worth noting I've made no theme changes and this problem is noted in both the Android and Apple skins as well as on an actual Android phone. Thanks in advance for any help!

Answer 1

You shouldn't do input in a Dialog as it creates a very problematic user experience. If you would like things to look like they are in a dialog you can use styles and layouts to make a Form feel like a Dialog but you shouldn't use a Dialog.
The reason this fails is a bit complicated but here are the high level problems with using a dialog:
Dialogs don't grow implicitly - This is a huge problem for text input as the component needs space to resize with input and even more so for the animated TextComponent which needs to shift things around. The size of a Dialog is determined when it's shown and that's a big problem
This becomes a bigger problem on Android where the screen resizes during input and distorts the dialog completely. It's one of those things you'll only see on the device because it's really hard to simulate the virtual keyboard.
Scrollability is hard in a Dialog and text components need a scrollable parent so you can scroll between the various edit components
Picker component uses a form of Dialog to show input and this can collide with your dialog
Dialogs are hard to get right for suspend/resume behavior. Suspend/resume happens when the app is minimized or sent to the background. E.g. say you have an incoming call while typing in the dialog. When you go back to the app we want to show the last form. If we show the dialog it will block and we won't know which parent form to show anyway. So when an app is suspended dialogs are just disposed in the default code generated in the main class. It makes more sense.