Skip to main content

dynamic - What is wrong with combining two programs with event handlers?


I can delete the unwanted nodes of a RandomGraph by double-clicking on them from the first program, and I can change the positions of the nodes by dragging them from the second program. They both work nicely. However, when I combined the two programs into one, the nodes can't be dragged anymore. What is wrong with the combined promgram? Please help.


(* First program, nodes can be deleted by double-clicking on them *)
DynamicModule[{rg },
 rg = RandomGraph[{7, 10}];
 edglst = EdgeList[rg];
 vlst = VertexList[rg];
 VPOS = VertexCoordinates /. AbsoluteOptions[rg, VertexCoordinates];

 VPOS = Rescale[#, 1 + Through[{Min, Max}[VPOS]], {0, 1}] & /@ VPOS;

 Vnthlrs = MapThread[EventHandler[#, {
      "MouseDown" :> If[CurrentValue["MouseClickCount"] == 2, ( 
         ep = First@Position[vlst, #];
         vlst = Drop[vlst, ep ];
         VPOS = Drop[VPOS, ep ];
         edglst = 
          Delete[edglst, Map[List, Position[edglst, #][[All, 1]]]];
         Vnthlrs = Drop[Vnthlrs, ep  ])]

      }] &, {vlst}];

  g = Dynamic@Graph[Vnthlrs, edglst,
    VertexCoordinates -> VPOS,
    VertexSize -> {.02, .02},
    VertexLabels -> "Name",
    PlotRange -> 1,
    EdgeStyle -> {Thick}
     ] 
  ]


(* Second program, nodes can be moved by dragging them *)
DynamicModule[{rg, refr = True},
 rg = RandomGraph[{7, 10}];
 edglst = EdgeList[rg];
 vlst = VertexList[rg];
 VPOS = VertexCoordinates /. AbsoluteOptions[rg, VertexCoordinates];
 VPOS = Rescale[#, 1 + Through[{Min, Max}[VPOS]], {0, 1}] & /@ VPOS;

 EventHandler[

  g = Dynamic@
    Graph[vlst, edglst, VertexCoordinates -> VPOS, 
     VertexSize -> {.02, .02},
     VertexLabels -> "Name",
     PlotRange -> 1,
     EdgeStyle -> {Thick}],
  {"MouseDown" :> (
      With[{pos = MousePosition["Graphics"]}, 
      ind = Position[VPOS, Nearest[VPOS, pos][[1]]][[1, 1]]]),


   "MouseDragged" :> 
    (VPOS[[ind ]] = MousePosition["Graphics"] )
     },
  PassEventsDown -> True
    ]
 ]

(* Combined *)
DynamicModule[{rg },
 rg = RandomGraph[{7, 10}];

 edglst = EdgeList[rg];
 vlst = VertexList[rg];
 VPOS = VertexCoordinates /. AbsoluteOptions[rg, VertexCoordinates];
 VPOS = Rescale[#, 1 + Through[{Min, Max}[VPOS]], {0, 1}] & /@ VPOS;

 Vnthlrs = MapThread[EventHandler[#, {
      "MouseDown" :> If[CurrentValue["MouseClickCount"] == 2, ( 
         ep = First@Position[vlst, #];
         vlst = Drop[vlst, ep ];
         VPOS = Drop[VPOS, ep ];

         edglst = 
          Delete[edglst, Map[List, Position[edglst, #][[All, 1]]]];
         Vnthlrs = Drop[Vnthlrs, ep  ])]
      }] &, {vlst}];

 EventHandler[
  g = Dynamic@
    Graph[Vnthlrs, edglst, VertexCoordinates -> VPOS, 
     VertexSize -> {.02, .02},
     VertexLabels -> "Name",

     PlotRange -> 1,
     EdgeStyle -> {Thick}],
  {"MouseDown" :> (
      With[{pos = MousePosition["Graphics"]}, 
      ind = Position[VPOS, Nearest[VPOS, pos][[1]]][[1, 1]]]),

   "MouseDragged" :> 
    (VPOS[[ind ]] = MousePosition["Graphics"] )
     },
  PassEventsDown -> True

  ]
 ]

Answer



Finally, I discovered that the combined program works fine as long as the dragging just begin from the point close to the node (not right on the top of it). Thanks.


Comments

Post a Comment

Popular posts from this blog

front end - keyboard shortcut to invoke Insert new matrix

I frequently need to type in some matrices, and the menu command Insert > Table/Matrix > New... allows matrices with lines drawn between columns and rows, which is very helpful. I would like to make a keyboard shortcut for it, but cannot find the relevant frontend token command (4209405) for it. Since the FullForm[] and InputForm[] of matrices with lines drawn between rows and columns is the same as those without lines, it's hard to do this via 3rd party system-wide text expanders (e.g. autohotkey or atext on mac). How does one assign a keyboard shortcut for the menu item Insert > Table/Matrix > New... , preferably using only mathematica? Thanks! Answer In the MenuSetup.tr (for linux located in the $InstallationDirectory/SystemFiles/FrontEnd/TextResources/X/ directory), I changed the line MenuItem["&New...", "CreateGridBoxDialog"] to read MenuItem["&New...", "CreateGridBoxDialog", MenuKey["m", Modifiers-...
Post a Comment
Read more

How to thread a list

I have data in format data = {{a1, a2}, {b1, b2}, {c1, c2}, {d1, d2}} Tableform: I want to thread it to : tdata = {{{a1, b1}, {a2, b2}}, {{a1, c1}, {a2, c2}}, {{a1, d1}, {a2, d2}}} Tableform: And I would like to do better then pseudofunction[n_] := Transpose[{data2[[1]], data2[[n]]}]; SetAttributes[pseudofunction, Listable]; Range[2, 4] // pseudofunction Here is my benchmark data, where data3 is normal sample of real data. data3 = Drop[ExcelWorkBook[[Column1 ;; Column4]], None, 1]; data2 = {a #, b #, c #, d #} & /@ Range[1, 10^5]; data = RandomReal[{0, 1}, {10^6, 4}]; Here is my benchmark code kptnw[list_] := Transpose[{Table[First@#, {Length@# - 1}], Rest@#}, {3, 1, 2}] &@list kptnw2[list_] := Transpose[{ConstantArray[First@#, Length@# - 1], Rest@#}, {3, 1, 2}] &@list OleksandrR[list_] := Flatten[Outer[List, List@First[list], Rest[list], 1], {{2}, {1, 4}}] paradox2[list_] := Partition[Riffle[list[[1]], #], 2] & /@ Drop[list, 1] RM[list_] := FoldList[Transpose[{First@li...
Post a Comment
Read more

mathematical optimization - Minimizing using indices, error: Part::pkspec1: The expression cannot be used as a part specification

I want to use Minimize where the variables to minimize are indices pointing into an array. Here a MWE that hopefully shows what my problem is. vars = u@# & /@ Range[3]; cons = Flatten@ { Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; Minimize[{Total@((vec1[[#]] - vec2[[u[#]]])^2 & /@ Range[1, 3]), cons}, vars, Integers] The error I get: Part::pkspec1: The expression u[1] cannot be used as a part specification. >> Answer Ok, it seems that one can get around Mathematica trying to evaluate vec2[[u[1]]] too early by using the function Indexed[vec2,u[1]] . The working MWE would then look like the following: vars = u@# & /@ Range[3]; cons = Flatten@{ Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; NMinimize[ {Total@((vec1[[#]] - Indexed[vec2, u[#]])^2 & /@ R...
Post a Comment
Read more