Let’s start at the beginning as Humpty Dumpty so wisely advised Alice. What is Git? — Git is a version control system.
A version control system is a program that helps you, essentially, keep copies of your work so that if something goes wrong (you screw up your code so badly you can’t fix it, for example) you can go back to the last working version.
Git also facilitates sharing code with teammates. If you work alone a version control system brings value in saving versions of your code and, if you use a service like GitHub, it keeps a copy of every version of your code off site, which is good in case your computer gets dropped into a pond.
There is much more you can do with it, but those are its essential functions.
Git is probably the world’s most popular version control system, even though it has a reputation (false) that it is very difficult to learn. We will demonstrate that it isn’t all that difficult after all.
This is a repost from 2009. It talks about breast cancer, but applies equally well to Covid testing, given the high percentage of false positives (not to mention the more worrisome false negatives). We simply are not wired well for probability…
1% of women at age forty who participate in routine screening have breast cancer. 80% of women with breast cancer will get positive mammographies. 9.6% of women without breast cancer will also get positive mammographies.
Suppose you have a collection of items and you want to display them in a ListView (Xamarin.Forms). The catch is that you want to change the display of each item depending on its state or some other code-based attributes.
At first glance this would seem very difficult, and you’d have to modify the instances in the collection to do so. This is where the DataTemplateSelector comes in.
In short, you create two or more data templates — one for each way you might want to display one of the items in your collection — and then you tell Xamarin.Forms, by way of the DataTemplateSelector, which data template to use.
Quite often we want to send an alert from the view model, but you can only do so from the view. We’ve tackled this problem in the past but we think there is room for a simplified and clear step by step explanation.