How do programatically sort a uitable?

Is there a way to programatically sort a uitable? Basically as if the user had pressed the sort button on the column header? My issue is that I'm programatically changing the .Data on the table, and if the table has been sorted it reverts to its unsorted order and there's no way to put it back. 'DisplayData' stores the data in its sorted order, but its read only, and there's seems to be no way to programatically change it. Any ideas?

[Mario Malic]

Maybe you could create a button with the callback to set the DisplayData to the Data property. In addition, you can also use UserData property for any reason, like saving the original data.

[Robert Aungst]

Changing Data is an option, but that defeats the purpose of having a DisplayData attribute. I'd like to leave Data alone as its referenced by other things and changing the order causes all sorts of other problems. I'm trying to programatically change Data, and have DisplayData update automatically based on how the user has sorted or rearranged things.

Answer 1

[Harimurali]

Hi Robert,

When the data in the "uitable" is changed programatically, instead of directly changing the data, the following can be done so that the data in the "uitable" is always sorted:

• Store the data in the "uitable" into a dummy variable
• Edit the data in the dummy variable
• Sort the data and store it back into the "uitable".

Here is an example MATLAB code to do the same (assuming "uit" is the "uitable" object:

newData = uit.Data;

newData{1,2} = 25; %changing the value in the second column in the first row

uit.Data = sortrows(newData, 2); %sorting based on the values in the second column

To provide more abstraction, a MATLAB function maybe defined to do the same:

function editTable(uit, row, col, val)

newData = uit.Data;

newData{row,col} = val;

uit.Data = sortrows(newData, col);

end

editTable(uit, 1, 2, 25)

The above code ensures that the data in the "uitable" is always sorted when the data in the table is changed programatically.

Callbacks maybe used to update the "uitable" automatically when some changes are made to the table via the table's user interface. Here is an example MATLAB code to do the same:

function uit = tableApp

% Create some sample data

data = {

'John Doe', 28, 'Male';

'Jane Smith', 34, 'Female';

'Emily Johnson', 40, 'Female';

'Michael Brown', 31, 'Male'

};

% Create UI figure

fig = uifigure;

% Create table UI component

uit = uitable(fig);

uit.Data = sortrows(data,2);

uit.ColumnSortable = false;

uit.ColumnEditable = [false true false];

sortColumn = 2;

uit.CellEditCallback = @(src,event) sortTable(src,sortColumn);

end

function sortTable(src,sortColumn)

sortedData = sortrows(src.Data, sortColumn);

src.Data = sortedData;

src.DisplayData

end

uit = tableApp

uit.Data{1,2} = 25

Refer the following Callbacks section of the given documentation for information about "uitable" callbacks:

https://www.mathworks.com/help/releases/R2022a/matlab/ref/matlab.ui.control.table-properties.html

Have a great day ahead.

Answer 2

[Pratyush]

Hi Robert ,

I understand that you want to programatically sort a 'uitable'.

In MATLAB, there isn't a built-in function to programmatically sort a 'uitable' as if a user clicked the column header. However, you can achieve a similar effect by sorting the data in your workspace and then updating the 'uitable' with the sorted data.

You could do the following:

1. Sort your data array or table based on the desired column using the 'sort' function for arrays or 'sortrows' for tables.
2. Update the 'uitable' with the sorted data by setting the 'Data' property of the 'uitable'.

To maintain the sort order after updating the data, you'll need to:

1. Store the last used sort criteria (column index and sort direction).
2. Apply the stored sort criteria to the new data before updating the `uitable`.

This workaround requires you to manage sorting manually each time you update the table's data.

[Robert Aungst]

Thanks! I was hoping there was some workaround to trigger the callback so that 'DisplayData' would update properly. The beauty of it is that you don't have to keep track of the sorted indices and .Selection updates correctly. Hopefully this is a feature added in the future.