在ImageView中缩放图像（javafx）
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我正在尝试使用滑块在ImageView中缩放选定的图像。我唯一能做的就是用图像调整整个ImageView的大小。但这不是我要寻找的。我想只使用具有相同大小的ImageView来缩放图像。这应该是焦距的证明。我也在使用场景建设者。我只是初学者，所以我非常感谢你的帮助。这就是我所拥有的。
public void openImage(ActionEvent event) {
FileChooser fc = new FileChooser();
File f = fc.showOpenDialog(null);
if (f != null) {
System.out.println(f.toURI().toString());
Obrazok = new Image(f.toURI().toString());
imageView.setImage(Obrazok);
imageView.setSmooth(true);
imageView.setCache(true);
}
}
public void setOnZoom (MouseEvent e){
imageView.scaleXProperty().bind(slider.valueProperty());
imageView.scaleYProperty().bind(slider.valueProperty());
Rectangle2D viewpoint = new Rectangle2D(0, 0, Obrazok.getRequestedHeight(), Obrazok.getRequestedWidth());
imageView.setViewport(viewpoint);
imageView.setViewport(viewpoint);
imageView.setImage(Obrazok);
}
答案
我不确定你想做什么！我有点使用James_D的建议
好吧我也是初学者，我花了差不多两个小时为你写这篇文章，希望有人读到这篇文章并发现它很有用
我只为png和jpg添加了ExtensionFilters，但是你可以添加javaFx支持的任何扩展名
（我使用滑块而不是滚动条导致我讨厌处理滚动条，但我相信你可以自己做）
更新：现在您可以在imageview上拖动以移动视口
package application;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import javafx.application.Application;
import javafx.geometry.Orientation;
import javafx.geometry.Pos;
import javafx.geometry.Rectangle2D;
import javafx.stage.FileChooser;
import javafx.stage.Stage;
import javafx.stage.FileChooser.ExtensionFilter;
import javafx.scene.Cursor;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Slider;
import javafx.scene.control.TextField;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
public class Main extends Application {
static double initx;
static double inity;
static int height;
static int width;
public static String path;
static Scene initialScene,View;
static double offSetX,offSetY,zoomlvl;
@Override
public void start(Stage s) {
s.setResizable(false);
GridPane grid = new GridPane();
grid.setHgap(20);grid.setVgap(20);
grid.setAlignment(Pos.CENTER);
Label hint = new Label("Select Your Image");
TextField URL = new TextField();
URL.setEditable(false);
URL.setPrefWidth(350);
Button browse = new Button("Browse");
FileChooser fc = new FileChooser();
ExtensionFilter png = new ExtensionFilter("png", "*.png");
ExtensionFilter jpg = new ExtensionFilter("jpg", "*.jpg");
fc.getExtensionFilters().addAll(png,jpg);
browse.setOnAction(e->{
URL.setText(fc.showOpenDialog(s).getAbsolutePath());
});
Button open = new Button("Open");
open.setOnAction(e->{
path = URL.getText();
initView();
s.setScene(View);
});
grid.add(hint, 0, 0);
grid.add(URL, 1, 0);
grid.add(browse, 2, 0);
grid.add(open, 2, 1);
initialScene = new Scene(grid,600,100);
s.setScene(initialScene);
s.show();
}
public static void initView(){
VBox root = new VBox(20);
root.setAlignment(Pos.CENTER);
Label title = new Label(path.substring(path.lastIndexOf("\")+1));
Image source = null;
try {
source = new Image(new FileInputStream(path));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
ImageView image = new ImageView(source);
double ratio = source.getWidth()/source.getHeight();
if(500/ratio < 500) {
width=500;
height=(int) (500/ratio);
}else if(500*ratio < 500){
height=500;
width=(int) (500*ratio);
}else {
height=500;
width=500;
}
image.setPreserveRatio(false);
image.setFitWidth(width);
image.setFitHeight(height);
height = (int) source.getHeight();
width = (int) source.getWidth();
System.out.println("height = "+height+"
width = "+width);
HBox zoom = new HBox(10);
zoom.setAlignment(Pos.CENTER);
Slider zoomLvl = new Slider();
zoomLvl.setMax(4);
zoomLvl.setMin(1);
zoomLvl.setMaxWidth(200);
zoomLvl.setMinWidth(200);
Label hint = new Label("Zoom Level");
Label value = new Label("1.0");
offSetX = width/2;
offSetY = height/2;
zoom.getChildren().addAll(hint,zoomLvl,value);
Slider Hscroll = new Slider();
Hscroll.setMin(0);
Hscroll.setMax(width);
Hscroll.setMaxWidth(image.getFitWidth());
Hscroll.setMinWidth(image.getFitWidth());
Hscroll.setTranslateY(-20);
Slider Vscroll = new Slider();
Vscroll.setMin(0);
Vscroll.setMax(height);
Vscroll.setMaxHeight(image.getFitHeight());
Vscroll.setMinHeight(image.getFitHeight());
Vscroll.setOrientation(Orientation.VERTICAL);
Vscroll.setTranslateX(-20);
BorderPane imageView = new BorderPane();
BorderPane.setAlignment(Hscroll, Pos.CENTER);
BorderPane.setAlignment(Vscroll, Pos.CENTER_LEFT);
Hscroll.valueProperty().addListener(e->{
offSetX = Hscroll.getValue();
zoomlvl = zoomLvl.getValue();
double newValue = (double)((int)(zoomlvl*10))/10;
value.setText(newValue+"");
if(offSetX<(width/newValue)/2) {
offSetX = (width/newValue)/2;
}
if(offSetX>width-((width/newValue)/2)) {
offSetX = width-((width/newValue)/2);
}
image.setViewport(new Rectangle2D(offSetX-((width/newValue)/2), offSetY-((height/newValue)/2), width/newValue, height/newValue));
});
Vscroll.valueProperty().addListener(e->{
offSetY = height-Vscroll.getValue();
zoomlvl = zoomLvl.getValue();
double newValue = (double)((int)(zoomlvl*10))/10;
value.setText(newValue+"");
if(offSetY<(height/newValue)/2) {
offSetY = (height/newValue)/2;
}
if(offSetY>height-((height/newValue)/2)) {
offSetY = height-((height/newValue)/2);
}
image.setViewport(new Rectangle2D(offSetX-((width/newValue)/2), offSetY-((height/newValue)/2), width/newValue, height/newValue));
});
imageView.setCenter(image);
imageView.setTop(Hscroll);
imageView.setRight(Vscroll);
zoomLvl.valueProperty().addListener(e->{
zoomlvl = zoomLvl.getValue();
double newValue = (double)((int)(zoomlvl*10))/10;
value.setText(newValue+"");
if(offSetX<(width/newValue)/2) {
offSetX = (width/newValue)/2;
}
if(offSetX>width-((width/newValue)/2)) {
offSetX = width-((width/newValue)/2);
}
if(offSetY<(height/newValue)/2) {
offSetY = (height/newValue)/2;
}
if(offSetY>height-((height/newValue)/2)) {
offSetY = height-((height/newValue)/2);
}
Hscroll.setValue(offSetX);
Vscroll.setValue(height-offSetY);
image.setViewport(new Rectangle2D(offSetX-((width/newValue)/2), offSetY-((height/newValue)/2), width/newValue, height/newValue));
});
imageView.setCursor(Cursor.OPEN_HAND);
image.setOnMousePressed(e->{
initx = e.getSceneX();
inity = e.getSceneY();
imageView.setCursor(Cursor.CLOSED_HAND);
});
image.setOnMouseReleased(e->{
imageView.setCursor(Cursor.OPEN_HAND);
});
image.setOnMouseDragged(e->{
Hscroll.setValue(Hscroll.getValue()+(initx - e.getSceneX()));
Vscroll.setValue(Vscroll.getValue()-(inity - e.getSceneY()));
initx = e.getSceneX();
inity = e.getSceneY();
});
root.getChildren().addAll(title,imageView,zoom);
View = new Scene(root,(image.getFitWidth())+70,(image.getFitHeight())+150);
}
public static void main(String[] args) {
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