Change the numer rows of a uitable in MATLAB gui automatically using GUIDE?

Question

Nikhil Tamhankar 2017-11-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/367892-change-the-numer-rows-of-a-uitable-in-matlab-gui-automatically-using-guide

评论： Vinayak Appasaheb Bhatte 2018-7-10

How to create an option (text box) to enter a number to automatically change the number rows of a uitable in MATLAB gui using GUIDE?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2017-11-19

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/367892-change-the-numer-rows-of-a-uitable-in-matlab-gui-automatically-using-guide#answer_291927

编辑：Walter Roberson 2017-11-20

在 MATLAB Online 中打开

uit = uitable('Data', [0 0 0]);
FirstN = @(Matrix, N) Matrix(1:N, :);
ChopN = @(Matrix, N) FirstN([Matrix; zeros(N, size(Matrix,2))], N);
uicontrol('style', 'edit', 'Callback', @(src, event) set(uit, 'data', ChopN(get(uit, 'data'), str2double(get(src, 'string'))));

10 个评论
显示 8更早的评论隐藏 8更早的评论

Walter Roberson 2017-11-21

在 MATLAB Online 中打开

You need a uitable to start with. For the code later to work properly, you cannot just initialize it with [] -- you have to initialize it with something with the same number of columns as you are going to use.

The uicontrol() call sets up the uicontrol text area that you want to control the number of rows in the table.

The Callback on the uicontrol is run when the user presses return inside the text area or clicks in the text area (possibly editing the text) and clicks outside the area.

The 'Callback' property of the uicontrol says which routine is to be run when the callback is triggered.

The callback to be run is the anonymous function

@(src, event) set(uit, 'data', ChopN(get(uit, 'data'), str2double(get(src, 'string'))

This is a function that takes two parameters, src and event and executes the code

set(uit, 'data', ChopN(get(uit, 'data'), str2double(get(src, 'string')))

using those two parameters. MATLAB automatically supplies those two parameters for every callback. The second of them is not important at the moment. The first parameter is the handle to the graphics object whose callback is being executed.

The code get(src, 'string') is taking that handle to the current uicontrol and fetching the String property, which is the property that stores the text that has been entered into the field.

str2double() of the string property converts the text representing a number into the number -- so if the user had entered the characters 127 into the field then the uicontrol would have stored that as '127' and you need to convert the text '127' into the number 127; the str2double does that.

For the code

get(uit, 'data')

you have to look back and see that I assigned the handle of the uitable to the variable uit . So get(uit, 'data') is fetching the current data property of the uitable.

Now, ChopN() is being called, with the first argument being the data pulled from the uitable, and the second argument being the number pulled from the edit field.

ChopN = @(Matrix, N) FirstN([Matrix; zeros(N, size(Matrix,2))], N);

tells us that ChopN is a function with two parameters. zeros(N, size(Matrix,2)) is called, which creates a block of zeros that is N rows high by the number of columns already in Matrix ("size of its second dimension"). That block of zeros is put onto the bottom of the existing block of data by way of the [Matrix; zeros...] operation. We know that the result must be at least N rows tall, and possibly taller, because of the N rows of zeros we put on the bottom. Now we call FirstN with that larger matrix together with N

FirstN = @(Matrix, N) Matrix(1:N, :);

tells us that FirstN is a function with two parameters. The function expects a matrix as input, and it extracts the first N rows of the matrix.

So ChopN adding N rows of zeros to the bottom and then calls FirstN to take the first N rows of that larger matrix. As noted above we know that there are at least N rows, so we know that extracting out the first N of the result will always be possible.

If you think about this a bit, what this combination of operations is doing is:

if the existing matrix was larger than the user specified in the edit field, then only the size specified by the user will be kept and the rest will be thrown away
if the existing matrix was smaller than the user specified in the edit field, then the matrix will be padded with exactly enough rows of zeros so that the result is the size the user requested.

set(uit, 'data', ....)

The result of this "adjust to be exactly the right length" operation is passed to set the data field of the uitable we defined earlier. So the uitable will be adjusted to the length the user specified.

To be honest, there are clearer ways of writing this code, by writing a real function to do the work instead of using anonymous functions. But writing a real function would require that I instruct you about how to write real functions and where they have to be stored and so on.

Walter Roberson 2018-7-10

在 MATLAB Online 中打开

You programmed a cell edit callback, which is a callback that activates when the user edits data in the uitable. If you want the change to happen when the user edits the edit box, then

function edit3_Callback(hObject, eventdata, handles)
  FirstN = @(Matrix, N) Matrix(1:N, :);
  ChopN = @(Matrix, N) FirstN([Matrix; zeros(N, size(Matrix,2))], N);
   set(handles.uitable1, 'Data', ChopN(get(handles.uitable1, 'Data'), str2double(get( hObject, 'string'))) )

Vinayak Appasaheb Bhatte 2018-7-10

Thanks a lot @Walter for your kind explanation, I did work finally.

请先登录，再进行评论。

Answer 2

Image Analyst 2017-11-20

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/367892-change-the-numer-rows-of-a-uitable-in-matlab-gui-automatically-using-guide#answer_292222

在 MATLAB Online 中打开

You can just assign the data to it and it will automatically adjust its size to handle/display all the rows and columns in your data matrix:

handles.uitable1.Data = yourData;

Or, you can just click on the little icon in the Columns entry in the Property Inspector, which you can bring up in GUIDE by double clicking on the table control.

3 个评论
显示 1更早的评论隐藏 1更早的评论

Image Analyst 2017-11-21

在 MATLAB Online 中打开

Basically get the string from the edit box

contentsString = handles.edit1.String;

Then parse contentsString to get what you want and expect - a row or whole matrix of whatever - and load that into yourData and then use the code I originally gave you:

handles.uitable1.Data = yourData;

Nikhil Tamhankar 2017-11-25

Thank you sir. Will try to understand your suggestion and try to implement it.

请先登录，再进行评论。

Change the numer rows of a uitable in MATLAB gui automatically using GUIDE?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

回答（2 个）

10 个评论
显示 8更早的评论隐藏 8更早的评论

3 个评论
显示 1更早的评论隐藏 1更早的评论

另请参阅

类别

标签

Community Treasure Hunt

Change the numer rows of a uitable in MATLAB gui automatically using GUIDE?

0 个评论 显示 -2更早的评论隐藏 -2更早的评论

回答（2 个）

10 个评论 显示 8更早的评论隐藏 8更早的评论

3 个评论 显示 1更早的评论隐藏 1更早的评论

另请参阅

类别

标签

Community Treasure Hunt

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

10 个评论
显示 8更早的评论隐藏 8更早的评论

3 个评论
显示 1更早的评论隐藏 1更早的评论