oopsie: class for page navigation

diff --git a/src/be/nikiroo/fanfix/reader/ui/GuiReaderNavBar.java b/src/be/nikiroo/fanfix/reader/ui/GuiReaderNavBar.java
new file mode 100644 (file)
index 0000000..0f3d8dc
--- /dev/null
+++ b/src/be/nikiroo/fanfix/reader/ui/GuiReaderNavBar.java
@@ -0,0 +1,329 @@
+package be.nikiroo.fanfix.reader.ui;
+
+import java.awt.Color;
+import java.awt.LayoutManager;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.swing.BoxLayout;
+import javax.swing.JButton;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+
+import be.nikiroo.fanfix.Instance;
+
+/**
+ * A Swing-based navigation bar, that displays first/previous/next/last page
+ * buttons.
+ * 
+ * @author niki
+ */
+public class GuiReaderNavBar extends JPanel {
+       private static final long serialVersionUID = 1L;
+
+       private JLabel label;
+       private int index = 0;
+       private int min = 0;
+       private int max = 0;
+       private JButton[] navButtons;
+       String extraLabel = null;
+
+       private List<ActionListener> listeners = new ArrayList<ActionListener>();
+
+       /**
+        * Create a new navigation bar.
+        * <p>
+        * The minimum must be lower or equal to the maximum.
+        * 
+        * @param min
+        *            the minimum page number
+        * @param max
+        *            the maximum page number
+        * 
+        * @throws IndexOutOfBoundsException
+        *             if min &gt; max
+        */
+       public GuiReaderNavBar(int min, int max) {
+               if (min > max) {
+                       throw new IndexOutOfBoundsException(String.format(
+                                       "min (%d) > max (%d)", min, max));
+               }
+
+               LayoutManager layout = new BoxLayout(this, BoxLayout.X_AXIS);
+               setLayout(layout);
+
+               navButtons = new JButton[4];
+
+               navButtons[0] = createNavButton("<<", new ActionListener() {
+                       @Override
+                       public void actionPerformed(ActionEvent e) {
+                               setIndex(GuiReaderNavBar.this.min);
+                       }
+               });
+               navButtons[1] = createNavButton(" < ", new ActionListener() {
+                       @Override
+                       public void actionPerformed(ActionEvent e) {
+                               setIndex(index - 1);
+                       }
+               });
+               navButtons[2] = createNavButton(" > ", new ActionListener() {
+                       @Override
+                       public void actionPerformed(ActionEvent e) {
+                               setIndex(index + 1);
+                       }
+               });
+               navButtons[3] = createNavButton(">>", new ActionListener() {
+                       @Override
+                       public void actionPerformed(ActionEvent e) {
+                               setIndex(GuiReaderNavBar.this.max);
+                       }
+               });
+
+               for (JButton navButton : navButtons) {
+                       add(navButton);
+               }
+
+               label = new JLabel("");
+               add(label);
+
+               this.min = min;
+               this.max = max;
+               this.index = min;
+
+               updateEnabled();
+               updateLabel();
+               fireEvent();
+       }
+
+       /**
+        * The current index, must be between {@link GuiReaderNavBar#min} and
+        * {@link GuiReaderNavBar#max}, both inclusive.
+        * 
+        * @return the index
+        */
+       public int getIndex() {
+               return index;
+       }
+
+       /**
+        * The current index, must be between {@link GuiReaderNavBar#min} and
+        * {@link GuiReaderNavBar#max}, both inclusive.
+        * 
+        * @param index
+        *            the new index
+        */
+       private void setIndex(int index) {
+               if (index != this.index) {
+                       if (index < min || index > max) {
+                               throw new IndexOutOfBoundsException(String.format(
+                                               "Index %d but min/max is [%d/%d]", index, min, max));
+                       }
+
+                       this.index = index;
+                       fireEvent();
+                       updateLabel();
+               }
+
+               updateEnabled();
+       }
+
+       /**
+        * The minimun page number.
+        * 
+        * @return the min
+        */
+       public int getMin() {
+               return min;
+       }
+
+       /**
+        * The minimum page number.
+        * <p>
+        * May update the index if needed (if the index is &lt; the new min).
+        * <p>
+        * Will also (always) update the label and enable/disable the required
+        * buttons.
+        * 
+        * @param min
+        *            the new min
+        */
+       public void setMin(int min) {
+               this.min = min;
+               if (index < min) {
+                       index = min;
+                       updateEnabled();
+                       updateLabel();
+                       fireEvent();
+               } else {
+                       updateEnabled();
+                       updateLabel();
+               }
+       }
+
+       /**
+        * The maximum page number.
+        * 
+        * @return the max
+        */
+       public int getMax() {
+               return max;
+       }
+
+       /**
+        * The maximum page number.
+        * <p>
+        * May update the index if needed (if the index is &gt; the new max).
+        * <p>
+        * Will also (always) update the label and enable/disable the required
+        * buttons.
+        * 
+        * @param max
+        *            the new max
+        */
+       public void setMax(int max) {
+               this.max = max;
+               if (index > max) {
+                       index = max;
+                       updateEnabled();
+                       updateLabel();
+                       fireEvent();
+               } else {
+                       updateEnabled();
+                       updateLabel();
+               }
+       }
+
+       /**
+        * The current extra label to display with the default
+        * {@link GuiReaderNavBar#computeLabel(int, int, int)} implementation.
+        * 
+        * @return the current label
+        */
+       public String getExtraLabel() {
+               return extraLabel;
+       }
+
+       /**
+        * The current extra label to display with the default
+        * {@link GuiReaderNavBar#computeLabel(int, int, int)} implementation.
+        * 
+        * @param currentLabel
+        *            the new current label
+        */
+       public void setExtraLabel(String currentLabel) {
+               this.extraLabel = currentLabel;
+               updateLabel();
+       }
+
+       /**
+        * Add a listener that will be called on each page change.
+        * 
+        * @param listener
+        *            the new listener
+        */
+       public void addActionListener(ActionListener listener) {
+               listeners.add(listener);
+       }
+
+       /**
+        * Remove the given listener if possible.
+        * 
+        * @param listener
+        *            the listener to remove
+        * @return TRUE if it was removed, FALSE if it was not found
+        */
+       public boolean removeActionListener(ActionListener listener) {
+               return listeners.remove(listener);
+       }
+
+       /**
+        * Remove all the listeners.
+        */
+       public void clearActionsListeners() {
+               listeners.clear();
+       }
+
+       /**
+        * Notify a chnge of page.
+        */
+       private void fireEvent() {
+               for (ActionListener listener : listeners) {
+                       try {
+                               listener.actionPerformed(new ActionEvent(this,
+                                               ActionEvent.ACTION_FIRST, "page changed"));
+                       } catch (Exception e) {
+                               Instance.getTraceHandler().error(e);
+                       }
+               }
+       }
+
+       /**
+        * Create a single navigation button.
+        * 
+        * @param text
+        *            the text to display
+        * @param action
+        *            the action to take on click
+        * @return the button
+        */
+       private JButton createNavButton(String text, ActionListener action) {
+               JButton navButton = new JButton(text);
+               navButton.addActionListener(action);
+               navButton.setForeground(Color.BLUE);
+               return navButton;
+       }
+
+       /**
+        * Update the label displayed in the UI.
+        */
+       private void updateLabel() {
+               label.setText(computeLabel(index, min, max));
+       }
+
+       /**
+        * Update the navigation buttons "enabled" state according to the current
+        * index value.
+        */
+       private void updateEnabled() {
+               navButtons[0].setEnabled(index > min);
+               navButtons[1].setEnabled(index > min);
+               navButtons[2].setEnabled(index < max);
+               navButtons[3].setEnabled(index < max);
+       }
+
+       /**
+        * Return the label to display for the given index.
+        * <p>
+        * Swing HTML (HTML3) is supported if surrounded by &lt;HTML&gt; and
+        * &lt;/HTML&gt;.
+        * <p>
+        * By default, return "Page 1/5: current_label" (with the current index and
+        * {@link GuiReaderNavBar#getCurrentLabel()}).
+        * 
+        * @param index
+        *            the new index number
+        * @param mix
+        *            the minimum index (inclusive)
+        * @param max
+        *            the maximum index (inclusive)
+        * @return the label
+        */
+       protected String computeLabel(int index,
+                       @SuppressWarnings("unused") int min, int max) {
+
+               String base = "&nbsp;&nbsp;<B>Page <SPAN COLOR='#444466'>%d</SPAN>&nbsp;/&nbsp;%d</B>";
+               String ifLabel = ": %s";
+
+               String display = base;
+               String label = getExtraLabel();
+               if (label != null && !label.trim().isEmpty()) {
+                       display += ifLabel;
+               }
+
+               display = "<HTML>" + display + "</HTML>";
+
+               return String.format(display, index, max, label);
+       }
+}