从网格窗格的各行内的动态创建的文本字段中提取文本 [英] Extracting text from dynamically created textfields inside various rows of gridpane
问题描述
我正在尝试在每行上创建一个带有文本框的网格，用户可以在其中输入一个数字，并添加相应数量的新行。这很有效，如下面的屏幕截图所示。
I'm trying to create a grid with a textbox on each row where user can enter a number, and corresponding number of new rows are added. This works well, as shown below in the screenshot.
现在我正在尝试从基于有多少问题创建的文本字段中提取文本？因为它们嵌套在各种节点元素中，所以我很难找到正确的方法。任何人都可以告诉我我做错了什么？我尝试使用保存按钮测试它，但我总是进入其他语句Vboxgrid2为空！在我的控制台上。我不知道为什么它说我的VBoxgrid2是空的！
Now I'm trying to extract the text from those textfields created based on the question "how many?" and since they are nested within various node elements, I'm having a hard time identifying the right way.Can anyone tell me what I'm doing wrong? I tried testing it using the save button, but I always go into the else statement of "Vboxgrid2 is empty!"on my console. I don't know why it says that my VBoxgrid2 is empty!
以下是我重新创建的一个Minimal，Complete和Verifiable示例：
Following is a Minimal, Complete, and Verifiable example I've recreated:
package testing;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class ExtractThatText extends Application {
@Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("GridPane Experiment");
GridPane gridPane = new GridPane();
for(int i=0;i<5;i++) {
VBox mainVBox = new VBox();
VBox vboxgrid1 = new VBox();
VBox vboxgrid2 = new VBox();
HBox hboxgrid = new HBox();
hboxgrid.setPadding(new Insets(5,5,5,5));
RadioButton rbYes = new RadioButton("Yes");
RadioButton rbNo = new RadioButton("No");
Label howmanyLabel = new Label(" How many? ");
TextField howManytxtB = new TextField();
hboxgrid.getChildren().add(rbYes);
hboxgrid.getChildren().add(rbNo);
hboxgrid.getChildren().add(howmanyLabel);
hboxgrid.getChildren().add(howManytxtB);
vboxgrid1.getChildren().add(hboxgrid);
howManytxtB.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
vboxgrid2.getChildren().clear();
Integer howManyNum = Integer.valueOf(howManytxtB.getText());
for(int row=0;row<howManyNum;row++) {
//creating rows for entering the new entities
HBox innerRowbox = new HBox();
TextField name = new TextField();
ComboBox cb = new ComboBox(); //empty cb for now
name.setPromptText("Enter name of the new Entity");
name.setMinWidth(200);
innerRowbox.getChildren().add(name);
innerRowbox.getChildren().add(cb);
vboxgrid2.getChildren().add(innerRowbox);
}
}
});
mainVBox.getChildren().add(vboxgrid1);
mainVBox.getChildren().add(vboxgrid2);
gridPane.add(mainVBox,1, i);
}
for(int i=0;i<5;i++) {
gridPane.add(new Label("row"+i), 0 , i);
}
Button saveButton = new Button("save content");
saveButton.setOnAction(e-> {
Node mainVBox = gridPane.getChildren().get(1); //get just the first row's 1th column which contains mainVBox
if(mainVBox instanceof VBox) {
Node vboxgrid2 = ((VBox) mainVBox).getChildren().get(1);
if(vboxgrid2 instanceof VBox) {
if(!((VBox) vboxgrid2).getChildren().isEmpty()) {
Node innerRowBox = ((VBox) vboxgrid2).getChildren().get(0);
if(innerRowBox instanceof HBox) {
for(Node howmanyTB:((HBox)innerRowBox).getChildren()) {
if(howmanyTB instanceof TextField) {
System.out.println(((TextField) howmanyTB).getText()); //content to save, extracted from the dnamic textfields created.
}
else System.out.println("howmanyTB not an instance of TextField error!");
}
}
else System.out.println("innerRowBox not an instance of HBox error!");
}
else System.out.println("Vboxgrid2 is empty!");
}
else System.out.println("vboxgrid2 not an instance of VBox error!");
}
else System.out.println("mainVbox not an instance of VBox error!");
});
gridPane.add(saveButton, 1, 5);
gridPane.setHgap(10);
gridPane.setVgap(10);
Scene scene = new Scene(gridPane, 500, 500);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
Application.launch(args);
}
}
**如果很难理解所有的嵌套我的节点，这是一个摘要：
** If it's difficult to understand the nesting of all my nodes, here is a summary:
gridPane - > mainVBox （在第二/第1列的每一行中） - > vboxgrid2 （以及<$ c）对于 mainVBox 中的radiobutton行，$ c> vboxgrid1 - > innerRowbox - > name （textfield）
gridPane -> mainVBox (in each row of the second/1th column) -> vboxgrid2 (along with vboxgrid1 above it for the radiobutton row in mainVBox) -> innerRowbox -> name (textfield)
推荐答案
如果很难理解我所有节点的嵌套
If it's difficult to understand the nesting of all my nodes
既然你似乎意识到你的嵌套有点令人困惑，最好将 TextField 保存在比场景层次结构更容易访问的数据结构中。在这种情况下，由于项目数量在创建之前是已知的，因此可以使用 TextField [] [] 数组，但您也可以使用列表< List< TextField>> ，允许您动态添加（内部）行。
Since you do seem to realize that your nesting is a bit confusing, it would be preferable to save the TextFields in a data structure that is easier to access than your scene hierarchy. In this case since the number of items is known before they are created, a TextField[][] array could be used, but you could also go for a List<List<TextField>> to allow you to dynamically add (inner) rows.
BTW：因为您使用索引 1 您访问第二行，而不是第一行。
BTW: since you use index 1 you access the second row, not the first one.
还使用 VBox 只是为了包含你的 HBox 似乎没必要。你可以直接使用 HBox ，因为 VBox 没有其他孩子。
Also using a VBox just to contain your HBox seems unnecessary. You could simply use the HBox directly, since the VBox has no other children.
Label howmanyLabel = new Label(" How many? ");
最好使用此间距而非空格的保证金。
Better use a margin for this spacing instead of spaces.
@Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("GridPane Experiment");
GridPane gridPane = new GridPane();
final int rowCount = 5;
TextField[][] textFields = new TextField[rowCount][0];
final Insets hboxPadding = new Insets(5);
final Insets labelMargin = new Insets(0, 15, 0, 15);
for (int i = 0; i < rowCount; i++) {
VBox vboxgrid2 = new VBox();
RadioButton rbYes = new RadioButton("Yes");
RadioButton rbNo = new RadioButton("No");
Label howmanyLabel = new Label("How many?");
HBox.setMargin(howmanyLabel, labelMargin);
TextField howManytxtB = new TextField();
HBox hboxgrid = new HBox(rbYes, rbNo, howmanyLabel, howManytxtB);
hboxgrid.setPadding(hboxPadding);
final int rowIndex = i;
howManytxtB.setOnAction(event -> {
vboxgrid2.getChildren().clear();
int howManyNum = Math.max(0, Integer.parseInt(howManytxtB.getText()));
TextField[] fields = new TextField[howManyNum];
for (int row = 0; row < howManyNum; row++) {
//creating rows for entering the new entities
TextField name = new TextField();
ComboBox cb = new ComboBox(); //empty cb for now
name.setPromptText("Enter name of the new Entity");
name.setMinWidth(200);
HBox innerRowbox = new HBox(name, cb);
vboxgrid2.getChildren().add(innerRowbox);
fields[row] = name;
}
textFields[rowIndex] = fields;
});
VBox mainVBox = new VBox(hboxgrid, vboxgrid2);
gridPane.addRow(i, new Label("row" + i), mainVBox);
}
Button saveButton = new Button("save content");
saveButton.setOnAction(e -> {
TextField[] secondRowFields = textFields[1];
if (secondRowFields.length == 0) {
System.out.println("no TextFields in row1");
} else {
for (TextField textField : secondRowFields) {
System.out.println(textField.getText());
}
}
});
gridPane.add(saveButton, 1, rowCount);
gridPane.setHgap(10);
gridPane.setVgap(10);
Scene scene = new Scene(gridPane, 500, 500);
primaryStage.setScene(scene);
primaryStage.show();
}
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