[TIMOB-26104] Android: Picker inside Tableview resets value

[ypbnv]

JIRA: https://jira.appcelerator.org/browse/TIMOB-26104

Description:
Persist the selection in a Picker in case it has to be refreshed\added again after being removed.

Note: This may not be the best experience if during the absence of the Picker from the screen it's adapter has been changed. Do you think it will be fine to reset the persisted index in that case?

Test case:
Removing and adding the picker again
app.js

var window = Ti.UI.createWindow();
var picker = Ti.UI.createPicker({ width: '50%' });
var rows = [];

for (var index = 0; index < 20; index++) {
	rows.push(Ti.UI.createPickerRow({ title: 'Item ' + (index + 1).toString() }));
}

picker.add(rows);

window.add(picker);

function createButtonText() {
	return window.children.includes(picker) ? 'Remove Picker' : 'Add Picker';
}

var button = Ti.UI.createButton({
	title: createButtonText(),
	bottom: '20dp',
});

button.addEventListener('click', function(e) {
	if (window.children.includes(picker)) {
		window.remove(picker);
	} else {
		window.add(picker);
	}

	button.title = createButtonText();
});

window.add(button);
window.open();

Using a Picker in a TableView
app.js

var currentwindow = Ti.UI.createWindow();

var tabledata = [];

var picker = Ti.UI.createPicker({ top:20 });

var data = [];
data[0]=Ti.UI.createPickerRow({title:'Bananas'});
data[1]=Ti.UI.createPickerRow({title:'Strawberries'});
data[2]=Ti.UI.createPickerRow({title:'Mangoes'});

picker.add(data);

var myrow=Ti.UI.createTableViewRow({ 'height' : '50sp' });

myrow.add(picker);
tabledata.push(myrow);

var infotableview = Titanium.UI.createTableView({ data:tabledata });

currentwindow.add(infotableview);
currentwindow.open();

Unit test added.

[build]

	Messages
📖	💾 Here's the generated SDK zipfile.

Generated by 🚫 dangerJS

[jquick-axway]

Question:
Do we need to store the last selection for each column as well? I'm okay with us writing that up as a separate ticket in order to resolve the community's issue with this today. Single selection pickers are the most common case.

This may not be the best experience if during the absence of the Picker from the screen it's adapter has been changed. Do you think it will be fine to reset the persisted index in that case?

To support this, our proxy's getter would have to return the proxy's lastSelectedIndex member variable instead of returning the index from native picker.

[garymathews]

@hansemannn @ypbnv iOS failed ios.Ti.UI.Picker | Selected index persistance

Is there an issue here?

[hansemannn]

@garymathews postlayout on iOS is only triggered if the layout actually changed. If the frame / origin of the view remains (like in this case), it is not fired. Can we change the test to not use the picker's postlayout event but the window's open / focus event? I rather would not change the iOS side to trigger a postevent on row-changes, since it seems Android-specific.

[ypbnv]

@hansemannn I will see if the test can use something different. I tried at first with events from the window, but got some mismatched timings.
And BTW is the disparity of when the postlayout is fired on Android and iOS something we should address? I have used it in a number of unit tests and it sounds like I may have to revisit that.

[ypbnv]

@hansemannn I am not particularly proud with the workaround for the unit test, but if I got it right now it should be fine on iOS too.

@jquick-axway Let's separate the multiple column persistence in another ticket then. I think it can be put together with the persistence across different data sets for both single and multiple column pickers.

[jquick-axway]

CR: Pass

[jquick-axway]

@hansemannn, @ypbnv,

I just tested add/removing the following picker types:

• For multicolumn spinner, both Android and iOS forget last selection.
• For date picker, iOS resets to current time. (Android remembers last selection.)
• For time picker, iOS resets to current time. (Android remembers last selection.)

I think the above are minor and low priority. I've written up the following tickets:

• TIMOB-26255
• TIMOB-26256
• TIMOB-26257

Edit:
Actually, I just discovered that iOS resets selection for single column picker. iOS fails this ticket's test case.

[keerthi1032]

FR Passed. Works fine. Some test are failing in jenkins. Not able to merge PR .Can somebody please look at it.
Name = Mac OS X
Version = 10.13.6
Architecture = 64bit
Node.js
Node.js Version = 8.9.1
npm Version = 5.5.1
Titanium CLI
CLI Version = 5.1.1

SDK =7.5.0.v20180901082336 local build
Studio = 5.1.1.201809051655
Device = samsung galaxy s5 -Android 6
Pixel emulator -Android 7