setting a different binding data context for different windows - wpf

Question

I have a window with some controls where some controls open up other windows with different controls. The bindings in the first window work great, and what's weird is the bindings in one of the new windows work well also. There is a third window where bindings don't seem to be working.
When I built the second window, to my surprise, I hadn't explicitly set the data context of its xaml bindings to be the xaml.cs partial class where all of the bound-to properties exist. But the second window has bindings and those work just fine.
This is very weird to me, as I clearly don't know how the data context and bindings work. For the third window I can't even get the bindings to show up even for a simple string property.
Can someone point me to a thorough discussion on how data binding works? I think it's fairly straightforward what I want to do, set the datacontext for each window's xaml to be the xaml.cs partial class associated with it. For the second window it seems like that happened automatically, but the third doesn't even seem to work with a simple string property.
Here are the bindings from the second window.
<TextBlock Name = "ObjectLatLon" Text= "{Binding hoveredObjectLatLon}" Background='White' Width="150" Height="20" Canvas.Top="5" Canvas.Left="685"/>
<TextBlock Name = "CursorLatLon" Text= "{Binding cursorLatLon, UpdateSourceTrigger=PropertyChanged}" Background='White' Width="150" Height="20" Canvas.Top="5" Canvas.Left="840"/>
<TextBlock Name = "TimeTextbox" Text= "{Binding winTime}" Background='White' Width="150" Height="20" Canvas.Top="5" Canvas.Left="1005"/>
Here are the code behind properties.
public string hoveredObjectLatLon
{
get { return HoveredObjectLatLon; }
set { HoveredObjectLatLon = value; ObjectLatLon.Text = hoveredObjectLatLon; }
}
public void cursorLatLon(object sender, MouseEventArgs e)
{
Point p = Mouse.GetPosition(FlatStanley);
double[] d = CanvasCoords_to_LatLon(new double[2] { p.Y, p.X });
p = new Point(d[0], d[1]);
CursorLatLon.Text = "Lat: " + Math.Round(p.X, 2).ToString() + " Lon: " + Math.Round(p.Y, 2).ToString();
}
private void hovered2dorbiter(object sender, MouseEventArgs e)
{
Shape o = sender as Shape;
double[] d = CanvasCoords_to_LatLon(new double[] { Canvas.GetTop(o) + (o.Height/2), Canvas.GetLeft(o) + (o.Width/2) });
hoveredObjectLatLon = "Lat: " + Math.Round(d[0],2) + " Lon: " + Math.Round(d[1], 2);
}
I'd like to know how these bindings can work but the third window, which isn't binding to a simple string property, will not work even if I explicitly state something like 'datacontext = this.' I looked through the second window's code and no where do i ever address the datacontext, but of course if I don't explicitly say 'datacontext = this' for the first window, all of its bindings are at risk of not working.
Basically, binding is very murky for me, not necessarily the mechanics of how a binding is supposed to work, but moreso the management of different datacontexts.
At the moment the thing I'm thinking is my only option is to make a class for every bit of data that will be bound to by any and all of the windows I'm incorporating bindings into and just go all out with putting everything in there. From what I've read, you can only have one data context across your solution. Is that the case? Or is there a simple enough functionality that I can work with to just simply have the datacontext of a MyWPFWindow.xaml window to be its MyWOFWindow.xaml.cs partial class counterpart.
I really can't get the datacontext to work with this third window at all.
Here is my XAML:
Window x:Class="COSTUMOBJECTSOLUTION.CUSTOMOBJECT_Window"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:CUSTOMOBJECTSOLUTION"
mc:Ignorable="d"
Title="CUSTOMOBJECT_Window" Height="300" Width="300">
<TextBlock Grid.Row ="0" Grid.Column="0" Name="COtextblock" Text="{Binding CO_Name}" VerticalAlignment="Center" HorizontalAlignment="Center"/>
In the code behind i say the following in the constructor:
DataContext = new CUSTOMOBJECT_ViewModel(customobject, mw);
And this is the viewmodel class I'm trying to get it to work for.
internal class CUSTOMOBJECT_ViewModel
{
CUSTOMOBJECT customobject;
MainWindow mW;
string CO_Name { get; set; }
public CUSTOMOBJECT_ViewModel(CUSTOMOBJECT custobj, MainWindow mw)
{
customobject = custobj;
mW = mw;
CO_Name = CUSTOMOBJECT.ObjectName;
}
}
But the objectname string is not ever showing up, it wasn't showing up when i tried it in the code-behind either.