How do I constrain nodes added to a GridPane in code?

Question

I have a need to add custom JavaFX controls to a grid pane in code. I set up the grid pane row and column constraints like so:

//These are doubles for the purposes of calculating more accurate percentages, see below.
//I feel like there should be a better way to accomplish this but I only want 5
//players per row, so the number of columns would be between 1 and 5 depending on the
//number of players, but if there are 5 or more, modulus doesn't work (5 % 5 = 0)... 
//I'm really bothered by this bit but it was the best I could devise.
double ColumnCount = Math.min(5, this.Settings.PlayerCount());
//This I feel fine with.
double RowCount = this.Settings.PlayerCount() / 5;

//The method encapsulating this code is for starting a new game. 
//This bit is for capturing player names for reassignment.
ArrayList<String> Names = new ArrayList<>();
if (this.Players.size()> 0)
    this.Players.stream().forEach((EQLPlayer plr) ->
        Names.add(plr.PlayerName())
    );

//This is for clearing the fields so they can be repopulated appropriately.
this.Players.clear();
this.gpPlayerField.getChildren().clear(); //<---- gpPlayerField is the GridPane with which I am working that I am trying to populate.
this.gpPlayerField.getColumnConstraints().clear();
this.gpPlayerField.getRowConstraints().clear();

//This bit is for setting up the Column and Row constraints.
for (int x = 0; x < ColumnCount; x++){
    ColumnConstraints CC = new ColumnConstraints();
    CC.setMaxWidth(200.00);
    CC.setPercentWidth( 100.00 / ColumnCount );
    CC.setHgrow(Priority.ALWAYS);
    this.gpPlayerField.getColumnConstraints().add(CC);
}
for (int x = 0; x < RowCount; x++){
    RowConstraints RC = new RowConstraints();
    RC.setMaxHeight(100.00);
    RC.setPercentHeight( 100.00 / RowCount );
    RC.setVgrow(Priority.ALWAYS);
    this.gpPlayerField.getRowConstraints().add(RC);
}

THIS is the problem area (I think, the rest of the code is in case I missed something stupidly obvious.

//I really feel like this should be working but it isn't.
//I want the rows and columns constrained to the size of the GridPane 
//(which is constrained to the stage) so that they will grow and shrink with it, but
//they are pretty much ignoring it.
for (int x = 0; x < this.Settings.PlayerCount(); x++){
    EQLPlayer plr = new EQLPlayer(x + 1);
    plr.GameMode(this.Settings.Mode());
    if (x < Names.size()) plr.PlayerName(Names.get(x));
    this.gpPlayerField.add(plr, x % 5, x / 5);
    GridPane.setHgrow(plr, Priority.ALWAYS);
    GridPane.setVgrow(plr, Priority.ALWAYS);
}

So the controls that I am adding have methods tied into them that will rescale all the labels when the control size changes. This worked fine when they were simply on a stage or scene, but now it won't work because they are just ignoring the constraints and I'm not certain why. I couldn't really find an example that demonstrated what it was I needed to do. I checked here and followed the example but that didn't work either. So... what am I doing wrong here? Is there a better way to go about achieving the results for which I am looking?

score 1 · Accepted Answer · answered Jul 28 '14 at 00:55

Alright so everything I did was correct. The issue I was having was the custom controls Minimum size and Maximum size were not set properly. To make this work (for the future in the unlikely event anyone runs into this), make certain your minimum size (both X and Y) and your maximum size (again) are set appropriately.

How do I constrain nodes added to a GridPane in code?

1 Answers1