Preview in image file selection dialogs

2026-09-25 08:20:45 +00:00 · 2021-03-12 22:12:39 +01:00
parent ea7ced017d
commit 9a394e422a
6 changed files with 134 additions and 11 deletions
@@ -0,0 +1,104 @@
+package com.jpexs.decompiler.flash.gui;
+
+import javax.swing.*;
+import java.beans.*;
+import java.awt.*;
+import java.io.File;
+import javax.swing.border.Border;
+
+public class FileChooserImagePreview extends JComponent
+        implements PropertyChangeListener {
+
+    ImageIcon thumbnail = null;
+    File file = null;
+
+    public static final int PREVIEW_SIZE = 150;
+
+    public FileChooserImagePreview(JFileChooser fc) {
+        setPreferredSize(new Dimension(PREVIEW_SIZE, 50));
+        fc.addPropertyChangeListener(this);
+
+        JLabel topLabel = new JLabel(AppStrings.translate("FileChooser.preview"), SwingConstants.CENTER);
+        Border b = UIManager.getBorder("FileChooser.listViewBorder");
+        topLabel.setBorder(b);
+        JPanel previewPanel = new JPanel() {
+            @Override
+            protected void paintComponent(Graphics g) {
+                if (thumbnail == null) {
+                    loadImage();
+                }
+                if (thumbnail != null) {
+                    int x = getWidth() / 2 - thumbnail.getIconWidth() / 2;
+                    int y = getHeight() / 2 - thumbnail.getIconHeight() / 2;
+
+                    if (y < 0) {
+                        y = 0;
+                    }
+
+                    if (x < 5) {
+                        x = 5;
+                    }
+                    thumbnail.paintIcon(this, g, x, y);
+                } else {
+                    String str = AppStrings.translate("FileChooser.previewNotAvailable");
+                    g.drawString(str, getWidth() / 2 - g.getFontMetrics().stringWidth(str) / 2, getHeight() / 2 + g.getFontMetrics().getHeight() / 2);
+                }
+            }
+        };
+        JPanel fullPanel = new JPanel(new BorderLayout());
+        fullPanel.add(topLabel, BorderLayout.NORTH);
+        fullPanel.add(previewPanel, BorderLayout.CENTER);
+        setLayout(new BorderLayout());
+        add(new JScrollPane(fullPanel), BorderLayout.CENTER);
+
+    }
+
+    public void loadImage() {
+        if (file == null) {
+            thumbnail = null;
+            return;
+        }
+
+        ImageIcon tmpIcon = new ImageIcon(file.getPath());
+
+        if (tmpIcon != null) {
+            if (tmpIcon.getImageLoadStatus() == MediaTracker.COMPLETE) {
+                if (tmpIcon.getIconWidth() > PREVIEW_SIZE) {
+                    thumbnail = new ImageIcon(tmpIcon.getImage().getScaledInstance(PREVIEW_SIZE, -1, Image.SCALE_DEFAULT));
+                } else { //no need to miniaturize
+                    thumbnail = tmpIcon;
+                }
+            } else {
+                thumbnail = null;
+            }
+
+        }
+    }
+
+    @Override
+    public void propertyChange(PropertyChangeEvent e) {
+        boolean update = false;
+        String prop = e.getPropertyName();
+
+        //If the directory changed, don't show an image.
+        if (JFileChooser.DIRECTORY_CHANGED_PROPERTY.equals(prop)) {
+            file = null;
+            update = true;
+
+            //If a file became selected, find out which one.
+        } else if (JFileChooser.SELECTED_FILE_CHANGED_PROPERTY.equals(prop)) {
+            file = (File) e.getNewValue();
+            update = true;
+        }
+
+        //Update the preview accordingly.
+        if (update) {
+            thumbnail = null;
+            if (isShowing()) {
+                loadImage();
+                repaint();
+            }
+        }
+    }
+
+}