我正在尝试模拟排序算法。所以我需要移动两个数字以显示它们之间的交换。但大多数时候，它开始从错误的地方搬到另一个错误的地方。这是我使用TranslateTransition的代码：
public static void showSwap(Text t1, Text t2)
{
double x1, x2, z;
x1=t1.getX();
x2=t2.getX();
z=x2-x1;
pt = new PauseTransition(Duration.millis(1000));
t1up = new TranslateTransition(Duration.millis(900), t1);
t1up.setFromY(0);
t1up.setToY(-55);
t1up.setCycleCount(1);
t1right = new TranslateTransition(Duration.millis(900), t1);
t1right.setFromX(0);
t1right.setToX(z);
t1right.setCycleCount(1);
t1down = new TranslateTransition(Duration.millis(900), t1);
t1down.setFromY(-55);
t1down.setToY(0);
t1down.setCycleCount(1);
t1.toFront();
sequentialTransition1.getChildren().addAll(t1up,t1right,t1down,pt);
t2down = new TranslateTransition(Duration.millis(900), t2);
t2down.setFromY(0);
t2down.setToY(55);
t2down.setCycleCount(1);
t2left = new TranslateTransition(Duration.millis(900), t2);
t2left.setFromX(0);
t2left.setToX(-z);
t2left.setCycleCount(1);
t2up = new TranslateTransition(Duration.millis(900), t2);
t2up.setFromY(55);
t2up.setToY(0);
t2up.setCycleCount(1);
t2.toFront();
sequentialTransition2.getChildren().addAll(t2down,t2left,t2up,pt);
}
我也试过这部分，但它得到了NullPointerException。
public static void showSwap2(Text t1, Text t2)
{
double x1, x2, y;
x1=t1.getX();
x2=t2.getX();
y=t1.getY();
MoveTo start1 = new MoveTo( x1, y );
ArcTo end1 = new ArcTo();
end1.setX(x2);
end1.setY(y);
end1.setRadiusX(100);
end1.setRadiusY(100);
Path path1 = new Path();
path1.getElements().addAll(start1, end1);
PathTransition transition1 = new PathTransition();
transition1.setDuration(Duration.millis(900));
transition1.setPath(path1);
sequentialTransition1.getChildren().addAll(transition1);
MoveTo start2 = new MoveTo( x1, y );
ArcTo end2 = new ArcTo();
end2.setX(x2);
end2.setY(y);
end2.setRadiusX(100);
end2.setRadiusY(100);
Path path2 = new Path();
path2.getElements().addAll( start2, end2 );
PathTransition transition2 = new PathTransition();
transition2.setDuration(Duration.millis(900));
transition2.setPath(path2);
sequentialTransition2.getChildren().addAll(transition2);
}
以下是我调用showSwap（）方法的部分：
public final class BubbleSort extends SimulatorController implements Initializable
{
public BubbleSort(Pane root,int totalNumbers)
{
int i, j, temp;
for (i = totalNumbers - 2; i >= 0; i--)
{
for (j = 0; j <= i; j++)
{
Simulator.showCompare(rect.get(j), rect.get(j+1));
if (numbers.get(j) > numbers.get(j + 1))
{
Simulator.showSwap(textNumbers.get(j),textNumbers.get(j+1));
temp = numbers.get(j);
numbers.set(j,numbers.get(j+1));
numbers.set(j+1,temp);
}
}
}
}
}
这是控制器类：
public class SimulatorController implements Initializable
{
@FXML protected Canvas img ;
@FXML protected Button prev;
@FXML protected Button next;
@FXML protected BorderPane root;
protected static SequentialTransition sequentialTransition1;
protected static SequentialTransition sequentialTransition2;
protected int totalNumbers=5;
protected static boolean nextMove=false;
protected static boolean prevMove=false;
protected static boolean simulateAutomatically=false;
protected static ArrayList<Rectangle> rect = new ArrayList<Rectangle>();
protected static ArrayList<Text> textNumbers=new ArrayList<Text>();
protected ArrayList<Text> textIndex=new ArrayList<Text>();
protected static ArrayList<Integer> numbers=new ArrayList<Integer>();
protected ArrayList<Integer> index=new ArrayList<Integer>();
protected static TranslateTransition t1right;
protected static TranslateTransition t1up;
protected static TranslateTransition t1down;
protected static TranslateTransition t2left;
protected static TranslateTransition t2down;
protected static TranslateTransition t2up;
protected static PauseTransition pt;
@Override
public void initialize(URL location, ResourceBundle resources)
{
drawArrayAndNumbers();
sequentialTransition1 = new SequentialTransition(); sequentialTransition2 = new SequentialTransition(); sequentialTransition1.setCycleCount(1); sequentialTransition2.setCycleCount(1);
new BubbleSort(root,totalNumbers);
sequentialTransition1.play();
sequentialTransition2.play();
root.setOnMouseClicked(new EventHandler<MouseEvent>()
{
@Override public void handle(MouseEvent mouseEvent)
{
System.out.println(("X="+mouseEvent.getScreenX()+" || Y="+mouseEvent.getScreenY()));
}
});
}
void drawArrayAndNumbers()
{
int i, x=50, y=250, rectSizeX=70, rectsizeY=50;
for(i=0;i<totalNumbers;i++,x+=rectSizeX+35)
{
rect.add(i, new Rectangle(x, y, rectSizeX, rectsizeY));
rect.get(i).setArcHeight(10);
rect.get(i).setArcWidth(10);
rect.get(i).setFill(Color.SKYBLUE);
numbers.add(i,100+(int)(Math.random()*899));
index.add(i);
textNumbers.add(i, new Text (x+15, y+30, Integer.toString(numbers.get(i))));
textNumbers.get(i).setFill(Color.BLACK);
textNumbers.get(i).setFont(new Font(25));
textIndex.add(i, new Text (x+30, y+rectsizeY+15, Integer.toString(i)));
textIndex.get(i).setFill(Color.BLACK);
textIndex.get(i).setFont(new Font(15));
root.getChildren().addAll(rect.get(i),textNumbers.get(i),textIndex.get(i));
}
}
}
这是完成TranslateTrasitions后的屏幕截图。我需要将数字保留在框内。但他们没有搬到正确的地方。
我该如何解决这些问题？
以下是完整套餐的下载链接：https://drive.google.com/folderview?id=0B7pxly3GctSNQ1FaajY4LTFOQnM&usp=sharing
答案 0 :(得分：1)
您使用x的{{1}}和y位置。然而，这是所有Text不常见的属性。动画属性是Node和translateX属性。因此
translateY导致x1=t1.getX();
x2=t2.getX();
z=x2-x1;
是原点x坐标之间差异的差异，而不是前一次转换后位置之间的差异。此外，您在动画完成之前调用此方法，因此即使您修复了前面提到的问题，也可以使用当前位置进行计算，而不是上一个动画之后z s的位置。
要解决此问题，请保存初始位置并使用Node属性定位节点：
translate圆形过渡的替代方案：
public class SwapAnimationQueue<T extends Node> {
private final SequentialTransition transitionUpper;
private final SequentialTransition transitionLower;
private final T[] nodes;
private final double[] positionX;
public SwapAnimationQueue(T... nodes) {
this.transitionLower = new SequentialTransition();
this.transitionUpper = new SequentialTransition();
this.nodes = nodes.clone();
positionX = new double[nodes.length];
for (int i = 0; i < nodes.length; i++) {
positionX[i] = nodes[i].getTranslateX();
}
}
public void play() {
this.transitionLower.play();
this.transitionUpper.play();
}
public void swap(int index1, int index2) {
if (index1 == index2) {
return;
}
T temp;
createTransition(transitionUpper, index1, index2, temp = nodes[index1], true);
createTransition(transitionLower, index2, index1, nodes[index2], false);
nodes[index1] = nodes[index2];
nodes[index2] = temp;
}
private void createTransition(SequentialTransition transition, int startPosition, int endPosition, Node node, boolean upper) {
double dy = upper ? -55 : 55;
TranslateTransition vertical1 = new TranslateTransition(Duration.millis(900), node);
vertical1.setByY(dy);
TranslateTransition horizontal = new TranslateTransition(Duration.millis(900), node);
horizontal.setByX(positionX[endPosition] - positionX[startPosition]);
TranslateTransition vertical2 = new TranslateTransition(Duration.millis(900), node);
vertical2.setByY(-dy);
transition.getChildren().addAll(vertical1, horizontal, vertical2);
}
}
private void createTransition(SequentialTransition transition, int startPosition, int endPosition, Node node, boolean upper) {
double x1 = positionX[startPosition];
double x2 = positionX[endPosition];
MoveTo move = new MoveTo(x1, node.getTranslateY());
double radius = Math.abs(x2-x1) / 2;
ArcTo arc = new ArcTo(radius, 20, 0, x2-x1, 0, upper, true);
arc.setAbsolute(false);
transition.getChildren().add(new PathTransition(Duration.millis(900), new Path(move, arc), node));
}