[JavaFX]绘制简易时钟(二)

原标题：[JavaFX] 绘制简易时钟(二)

在前一篇博客中，我们已经绘制了一个静止时钟。
绘制简易时钟（一）

• 首先进行一个微调：让表盘根据窗口大小自动调整大小：
  在 ShowClock.start() 中，添加对面板长宽的监听。

pane.widthProperty().addListener(ov -> clock.setW(pane.getWidth()));
pane.heightProperty().addListener(ov -> clock.setH(pane.getHeight()));


• 添加对时间和钟表大小的更改方法
  在 ClockPane 类中添加：

/** Construct a clock with specified hour, minute, and second */
public ClockPane(int hour, int minute, int second) {
this.hour = hour;
this.minute = minute;
this.second = second;
paintClock();
}
/** Set a new hour */
public void setHour(int hour) {
this.hour = hour;
paintClock();
}
/** Set a new minute */
public void setMinute(int minute) {
this.minute = minute;
paintClock();
}
/** Set a new second */
public void setSecond(int second) {
this.second = second;
paintClock();
}
/** Return clock pane's width */
public double getW() {
return w;
}
/** Set clock pane's width */
public void setW(double w) {
this.w = w;
paintClock();
}
/** Return clock pane's height */
public double getH() {
return h;
}
/** Set clock pane's height */
public void setH(double h) {
this.h = h;
paintClock();
}


• 用 Timeline 实现动态钟表
  在 ShowClock 类中添加：

//设置事件处理对象
EventHandler<ActionEvent> eventHandler = e -> {
clock.setCurrentTime();
};
//每秒结束后触发eventHandler
Timeline animation = new Timeline(
new KeyFrame(Duration.millis(1000), eventHandler));
animation.setCycleCount(Timeline.INDEFINITE); //无限循环
animation.play(); //开始动画


就可以让时钟动起来了。

完整代码
ShowClock.java

package primier;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.scene.layout.*;
import javafx.scene.control.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.util.Duration;
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
public class ShowClock extends Application {
@Override //Override the start method in the Application class
public void start(Stage primaryStage) {
ClockPane clock = new ClockPane();
/文章来源地址34654.html/设置事件处理对象
EventHandler<ActionEvent> eventHandler = e -> {
clock.setCurrentTime();
};
//每秒结束后触发eventHandler
Timeline animation = new Timeline(
new KeyFrame(Duration.millis(1000), eventHandler));
animation.setCycleCount(Timeline.INDEFINITE); //无限循环
animation.play(); //开始动画
BorderPane pane = new BorderPane();
pane.setCenter(clock);
Scene scene = new Scene(pane, 250,250);
p文章来源站点https://www.yii666.com/rimaryStage.setTitle("Display Clock");
primaryStage.setScene(scene);
primaryStage.show();
pane.widthProperty().addListener(ov ->
clock.setW(pane.getWidth()));
pane.heightProperty().addListener(ov ->
clock.setH(pane.getHeight()));
}
public static void main (String[] args) { Application.launch(args); }
}


ClockPane.java

package primier;
import java.util.Calendar;
import java.util.GregorianCalendar;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Line;
import javafx.scene.text.Text;
public class ClockPane extends Pane {
private int hour;
private int minute;
private int second;
// Clock pane's width and height
private double w = 250, h = 250;
/** Construct a default clock with the current time*/
public ClockPane() {
setCurrentTime();
}
/** Construct a clock with specified hour, minute, and second */
public ClockPane(int hour, int minute, int second) {
this.hour = hour;
this.min文章来源地址34654.htmlute = minute;
this.second = second;
paintClock();
}
/** Return hour */
public int getHour() {
return hour;
}
/** Set a new hour */
public void setHour(int hour) {
this.hour = hour;
paintClock();
}
/** Return minute */
public int getMinute() {
return minute;
}
/*www.yii666.com* Set a new minute */
public void setMinute(int minute) {
this.minute = minute;
paintClock();
}
/** Return second */
public int getSecond() {
return second;
}
/** Set a new second */
public void setSecond(int second) {
this.second = second;
paintClock();
}
/** Return clock pane's width */
public double getW() {
return w;
}
/** Set clock pane's width */
public void setW(double w) {
this.w = w;
paintClock();
}
/** Return clock pane's height */
public double getH() {
return h;
}
/** Set clock pane's height */
public void setH(double h) {
this.h = h;
paintClock();
}
/** Set the current time for the clock */
public void setCurrentTime() {
//Construct a calendar for the current date and time
Calendar calendar = new GregorianCalewww.yii666.comndar();
//Set current hour, minute and second
this.hour = calendar.get(Calendar.HOUR_OF_DAY);
this.minute = calendar.get(Calendar.MINUTE);
this.second = calendar.get(Calendar.SECOND);
paintClock();
}
/** Paint the clock */
protected void paintClock() {
// Initialize clock parameters
double clockRadius = Math.min(w,h)*0.8*0.5;
double centerX = w/2;
double centerY = h/2;
// Draw circle
Circle circle = new Circle(centerX, centerY, clockRadius);
circle.setFill(Color.WHITE);
circle.setStroke(Color.BLACK);
Text t1 = new Text(centerX-5, centerY-clockRadius+12,"12");
Text t2 = new Text(centerX-clockRadius+3, centerY +5, "9");
Text t3 = new Text(centerX+clockRadius-10, centerY+3, "3");
Text t4 = new Text(centerX-3, centerY+clockRadius-3,"6");
// Draw second hand
double sLength = clockRadius * 0.8;
double secondX = centerX + sLength * Math.sin(second * (2 * Math.PI / 60));
double secondY = centerY - sLength * Math.cos(second * (2 * Math.PI / 60));
Line sLine = new Line(centerX, centerY, secondX, secondY);
sLine.setStroke(Color.GRAY);
// Draw minute hand
double mLength = clockRadius * 0.65;
double minuteX = centerX + mLength * Math.sin(minute * (2 * Math.PI / 60));
double minuteY = centerY - mLength * Math.cos(minute * (2 * Math.PI / 60));
Line mLine = new Line(centerX, centerY, minuteX, minuteY);
mLine.setStroke(Color.BLUE);
// Draw hour hand
double hLength = clockRadius * 0.5;
double hourX = centerX + hLength *
Math.sin((hour % 12 + minute / 60.0) * (2 * Math.PI / 12));
double hourY = centerY - hLength *
Math.cos((hour % 12 + minute / 60.0) * (2 * Math.PI / 12));
Line hLine = new Line(centerX, centerY, hourX, hourY);
sLine.setStroke(Color.GREEN);
getChildren().clear();
getChildren().addAll(circle, t1, t2, t3, t4, sLine, mLine, hLine);
}
}


来源于：[JavaFX] 绘制简易时钟(二)