我有一个JavaFX 2 GUI，其中包括一个HBox填充GridPane的单元格之一。我所有的组件都是动态调整大小的。这显示正常，没有问题。
第一个问题：我想将HBox的内容剪切到它们所在的GridPane单元格的边缘，这样就不会显示任何溢出，但是我无法解决。我尝试将HBox的剪辑设置为相同大小的矩形，但这不起作用。我猜是因为它使用的是用于布局的尺寸，而不是所显示内容的尺寸。我应该改用GridPane本身，还是至少使用其属性？
第二个问题（要点）：剪辑与Node的平移和缩放如何相互作用？
谢谢你的帮助。
最佳答案
我尝试了一些简短的程序，试图在GridPane中剪辑节点。
我没有一个很好的尝试剪辑实现的方法，尽管它们大多数都以某种方式或其他方式根据要求工作。
看起来最适合您的描述的剪辑尝试是最后一次使用其自身的大小指定符将修剪的节点包装到一个区域中，从而使修剪的区域的布局与应用于该节点的剪贴节点的大小匹配。
class ClippedNode extends Region {
private final Node content;
private final double width;
private final double height;
ClippedNode(Node content, double width, double height) {
this.content = content;
this.width = width;
this.height = height;
content.setClip(new Rectangle(width, height));
getChildren().setAll(content);
}
@Override protected double computeMinWidth(double d) { return width; }
@Override protected double computeMinHeight(double d) { return height; }
@Override protected double computePrefWidth(double d) { return width; }
@Override protected double computePrefHeight(double d) { return height; }
@Override protected double computeMaxWidth(double d) { return width; }
@Override protected double computeMaxHeight(double d) { return height; }
}
下面提供了演示各种剪辑方法的完整可执行示例：
import java.util.Iterator;
import javafx.application.Application;
import javafx.beans.value.*;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.scene.shape.Rectangle;
import javafx.scene.text.Text;
import javafx.stage.Stage;
public class GridClipping extends Application {
String buttonText[] = "The quick brown fox jumped over the lazy dog".split(" ");
String[] colors = { "aqua", "coral", "cornsilk", "cornflowerblue" };
@Override public void start(Stage stage) throws Exception {
final GridPane grid = new GridPane();
grid.addRow(0, createHBox("aqua"), createHBox("coral"));
grid.addRow(1, createHBox("cornsilk"), createHBox("cornflowerblue"));
grid.setStyle("-fx-border-color: red;");
final GridPane gridWithClippedBoxes = new GridPane();
gridWithClippedBoxes.addRow(0, createClipWrappedHBox("aqua"), createClipWrappedHBox("coral"));
gridWithClippedBoxes.addRow(1, createClipWrappedHBox("cornsilk"), createClipWrappedHBox("cornflowerblue"));
gridWithClippedBoxes.setStyle("-fx-border-color: red;");
final RadioButton noClip = new RadioButton("No Clip");
final RadioButton restrictGridSize = new RadioButton("Restrict Max Grid Size (doesn't work)");
final RadioButton clipGrid = new RadioButton("Clip Grid");
final RadioButton clipHBoxes = new RadioButton("Clip HBoxes");
final RadioButton clipWrappedHBoxes = new RadioButton("Clip Wrapped HBoxes");
final ToggleGroup clipRadios = new ToggleGroup();
clipRadios.getToggles().setAll(
noClip,
restrictGridSize,
clipGrid,
clipHBoxes,
clipWrappedHBoxes
);
final Rectangle gridClip = new Rectangle(0, 0, 100, 25);
clipGrid.selectedProperty().addListener(new ChangeListener<Boolean>() {
@Override public void changed(ObservableValue<? extends Boolean> ov, Boolean wasClipped, Boolean clipped) {
if (clipped != null) {
if (clipped) {
grid.setClip(gridClip);
} else {
grid.setClip(null);
}
}
}
});
restrictGridSize.selectedProperty().addListener(new ChangeListener<Boolean>() {
@Override public void changed(ObservableValue<? extends Boolean> ov, Boolean wasClipped, Boolean clipped) {
if (clipped != null) {
if (clipped) {
// this does not work in our case.
// the minimum size of the grid components > the max size of the grid.
// so the grid expands in size to fit the minimum size of it's components anyway.
grid.setMaxSize(100, 25);
} else {
grid.setMaxSize(Double.MAX_VALUE, Double.MAX_VALUE);
}
}
}
});
clipHBoxes.selectedProperty().addListener(new ChangeListener<Boolean>() {
@Override public void changed(ObservableValue<? extends Boolean> ov, Boolean wasClipped, Boolean clipped) {
if (clipped != null) {
if (clipped) {
for (Node gridCell: grid.getChildren()) {
Rectangle cellClip = new Rectangle(100, 12);
gridCell.setClip(cellClip);
}
} else {
for (Node gridCell: grid.getChildren()) {
gridCell.setClip(null);
}
}
}
}
});
final VBox layout = new VBox(10);
clipWrappedHBoxes.selectedProperty().addListener(new ChangeListener<Boolean>() {
@Override public void changed(ObservableValue<? extends Boolean> ov, Boolean wasClipped, Boolean clipped) {
if (clipped != null) {
if (clipped) {
layout.getChildren().set(0, gridWithClippedBoxes);
} else {
layout.getChildren().set(0, grid);
}
}
}
});
noClip.fire();
layout.setStyle("-fx-background-color: cornsilk; -fx-padding: 10;");
layout.getChildren().setAll(
grid,
noClip,
restrictGridSize,
clipGrid,
clipHBoxes,
clipWrappedHBoxes
);
stage.setScene(new Scene(layout));
stage.show();
}
private Region createHBox(String webColor) {
HBox box = new HBox(5);
box.setStyle("-fx-background-color: " + webColor + ";");
for (String text: buttonText) {
box.getChildren().add(new Text(text));
}
box.setOpacity(0.5);
return box;
}
private Region createClipWrappedHBox(String webColor) {
return new ClippedNode(createHBox(webColor), 100, 12);
}
class ClippedNode extends Region {
private final Node content;
private final double width;
private final double height;
ClippedNode(Node content, double width, double height) {
this.content = content;
this.width = width;
this.height = height;
content.setClip(new Rectangle(width, height));
getChildren().setAll(content);
}
@Override protected double computeMinWidth(double d) { return width; }
@Override protected double computeMinHeight(double d) { return height; }
@Override protected double computePrefWidth(double d) { return width; }
@Override protected double computePrefHeight(double d) { return height; }
@Override protected double computeMaxWidth(double d) { return width; }
@Override protected double computeMaxHeight(double d) { return height; }
}
public static void main(String[] args) { Application.launch(args); }
}
关于javafx-2 - 在GridPane中剪辑HBox，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/15476063/