How to pause calculation waiting for the variable return from Dialog box

Questions
,
1

I have a long script, in the middle of it I have this dialog window:

CreateWindow[
  DialogNotebook[{TextCell["Where to insert new rows? "], 
    InputField[Dynamic[nm], String], 
    Row[{DefaultButton[DialogReturn[kk = nm]], CancelButton[]}]}]];

How can I pause and wait till one enters the value nm and then after it proceed with updated variable kk which is being used further forward? Thanks.

2

Use DialogInput instead of CreateWindow.

3

Thanks.

4

But even with this it doesn’t seem to pause and wait. In the code below, it should bring a matrix of InputFields and then when you increase n (main entry variable), it should Insert a row in the matrix, but it doesn’t:

Clear[f, kk];
T = {}; kk = Null;
InputField[Dynamic[n,
  {n = #;
    
    AppendTo[T, n];
    
    If[Length[T] == 1, A = Array[c, 3 n],
     
     If[Length[T] >= 2,   
      
      DialogInput[
       DialogNotebook[{TextCell["Where to insert new rows? "], 
         InputField[Dynamic[nm], String], 
         Row[{DefaultButton[DialogReturn[kk = nm]], 
           CancelButton[]}]}]];
      
      A = 
       Flatten@Insert[A, Table[c, {i, 3 ( T[[-1]] - T[[-2]])}], 
         3 kk]; Print[kk];
      
      ]
     ];
    Print[kk];
    Print@
     Grid[Table[{"Amp", i, " = ", 
        With[{i = i}, 
         InputField[Dynamic[A[[3 i - 2]]], FieldSize -> Tiny]],
        
        "\[Mu]", i, " = ", 
        With[{i = i}, 
         InputField[Dynamic[A[[3 i - 1]]], FieldSize -> Tiny]],
        
        "\[Sigma]", i, " = ", 
        With[{i = i}, InputField[Dynamic[A[[3 i]]], FieldSize -> Tiny]]
        
        }, {i, n}]];
    
    f = Sum[
      A[[3 i - 2]] *Sqrt[2 \[Pi]]
        A[[3 i]] PDF[NormalDistribution[A[[3 i - 1]], A[[3 i]]], 
        t], {i, n}];
    
    
    Print@
     Show[ListPlot[gr3, Joined -> True], 
      Plot[f, {t, -1.8, -1.10}, PlotStyle -> Red]]
    
    
    } &]]

Not sure I understand why.

5

The problem is that Dynamic uses preemptive link, which is not queued. It does what it can as soon as it can. Take a look at Advanced Dynamic Functionality tutorial.

Currently only Button and ActionMenu is able to execute on main link, with Method->"Queued".

You could try to walk-around that with SynchronousUpdating->False which will send evaluation from Dynamic object via main link. It does not really work with Dynamic inside controllers like InputField.

6

I see the problem now. thanks.

Why is it when I put semicolon after Dynamics it’s not being evaluated?

7

If you are interested in Dynamic and making user interfaces with Mathematica then:

  • Introdution to Dynamic
  • Advanced Dynamic Functionality

tutorials are a must. I’m higly encouraging you to go through them before you proceed, it will save your time in the future.

Your problem is described in the former one. This is a fundamental property of Dynamic, it matters only when displayed.