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I just migrated .NET Core 2.0 to .NET Core 2.1. Everything went fine, but when I try to login now I get the folowing error:

• $exception {System.ObjectDisposedException: Cannot access a disposed object. Object name: 'IServiceProvider'.

This happens in this bit of code:

If I call ((MainActivity)getActivity()).clearApp(); in my PrefsFragment. I get this error... why?

How can I fix this iusse and get understand this error.

I'm needing to filter images based on category in the model. I've created buttons for the category. E.g. if user presses Lake Pics button, would like it to filter all of the images with the category 'lake' in the model or if Family Pics selected, filter all of the images with category 'family' etc. All of the examples I've found and researched have static image links within the HTML. But i would like to derive everything from the model. What would be the best way to approach this programatic?

I have a list of names from the model that are listed on the page when the page loads. When i click the name, the corresponding image from the model appears on the page. Is there a way within this to load an initial image [0]when the page loads? This could be a random image or the first image in the model data set.

I've got a multiindex dataframe which I have to save as an excel file. When I use pandas method "to_excel" to do so, I get a nice table which incorporates merged cells. Here is an example of how such a table looks like:

Unfortunately, filtering the first column of this table is very problematic in excel since excel does not understand that the merged cells belong together: https://www.extendoffice.com/documents/excel/1955-excel-filter-merged-cells.html

That's why I need the 'to_excel' method to save the dataframe like that:

Is that possible?

By the way, that's the code which I used to produce the first table:

I currently have this image:

I managed to detect the black object. Now i want to detect the green object, but i only want the application to look for the green object below the black object. I already have the code to detect the green tape and its working. Just need to set it so that its only in the area below the black object.

Resulting image should still look like this:

P.S some of the variables are named "Blue", rest assured its using Green scalar values.

Code:

I'm running into this case where a dropdown's bound value observable isn't synced automatically when the dropdown is changed from a computable KO property. It's a bit tricky because the dropdown is populated from a value selected in another dropdown, but to make this more clear I created this test fiddle which demonstrates the problem: https://jsfiddle.net/n3wjack/gzmb792p/

Here's how to simulate the issue:

• In the pet dropdown, select "Mozart", John's second pet. You'll see the 'selected pet' label update.
• Now choose Jane in the first dropdown. The second dropdown will update, showing Jane's pets.

The selected pet label is not updated to show the name of Jane's first pet. If you make changes tot the pet dropdown, the value is updated again. I can't guarantee the user will do this, so I'm not sure if the value will be correct.

So how do I fix this, or what am I doing wrong?

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I'm also including the code below, cause apparently that's required.

JS:

There is already information about what I want to do, but couldn't figure it out yet. I would like to instantiate an element of a type passed as a context bound, something like this: