SystemTray/src/dorkbox/systemTray/swing/SwingSystemTray.java

/*
 * Copyright 2014 dorkbox, llc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package dorkbox.systemTray.swing;

import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Image;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.SystemTray;
import java.awt.TrayIcon;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.File;
import java.util.concurrent.atomic.AtomicInteger;

import javax.swing.ImageIcon;

import dorkbox.systemTray.MenuEntry;
import dorkbox.systemTray.SystemTrayMenuAction;
import dorkbox.systemTray.util.ImageUtils;
import dorkbox.util.ScreenUtil;
import dorkbox.util.SwingUtil;

/**
 * Class for handling all system tray interaction, via SWING.
 *
 * It doesn't work well on linux. See bugs:
 * http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6267936
 * http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6453521
 * https://stackoverflow.com/questions/331407/java-trayicon-using-image-with-transparent-background/3882028#3882028
 */
@SuppressWarnings({"SynchronizationOnLocalVariableOrMethodParameter", "WeakerAccess"})
public
class SwingSystemTray extends dorkbox.systemTray.SystemTray {
    static final AtomicInteger MENU_ID_COUNTER = new AtomicInteger();

    volatile SwingSystemTrayMenuPopup menu;

    volatile SystemTray tray;
    volatile TrayIcon trayIcon;

    volatile boolean isActive = false;

    /**
     * Creates a new system tray handler class.
     */
    public
    SwingSystemTray() {
        super();

        ImageUtils.determineIconSize(dorkbox.systemTray.SystemTray.TYPE_SWING);

        SwingUtil.invokeAndWait(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray.this.tray = SystemTray.getSystemTray();
                if (SwingSystemTray.this.tray == null) {
                    logger.error("The system tray is not available");
                }
            }
        });
    }


    @Override
    public
    void shutdown() {
        SwingUtil.invokeAndWait(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray tray = SwingSystemTray.this;
                synchronized (tray) {
                    tray.tray.remove(tray.trayIcon);

                    for (MenuEntry menuEntry : tray.menuEntries) {
                        menuEntry.remove();
                    }
                    tray.menuEntries.clear();
                }
            }
        });
    }

    protected SwingSystemTrayMenuPopup getMenu() {
        return menu;
    }


    @Override
    public
    String getStatus() {
        synchronized (menuEntries) {
            MenuEntry menuEntry = menuEntries.get(0);
            if (menuEntry instanceof SwingMenuEntryStatus) {
                return menuEntry.getText();
            }
        }

        return null;
    }

    protected
    void dispatch(final Runnable runnable) {
        // this will properly check if we are running on the EDT
        SwingUtil.invokeLater(runnable);
    }

    @Override
    public
    void setStatus(final String statusText) {
        dispatch(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray tray = SwingSystemTray.this;
                synchronized (tray) {
                    synchronized (menuEntries) {
                        // status is ALWAYS at 0 index...
                        SwingMenuEntry menuEntry = null;
                        if (!menuEntries.isEmpty()) {
                            menuEntry = (SwingMenuEntry) menuEntries.get(0);
                        }

                        if (menuEntry instanceof SwingMenuEntryStatus) {
                            // set the text or delete...

                            if (statusText == null) {
                                // delete
                                removeMenuEntry(menuEntry);
                            }
                            else {
                                // set text
                                menuEntry.setText(statusText);
                            }

                        } else {
                            // create a new one
                            menuEntry = new SwingMenuEntryStatus(statusText, tray);
                            // status is ALWAYS at 0 index...
                            menuEntries.add(0, menuEntry);
                        }
                    }
                }
            }
        });
    }


    @Override
    public
    void addMenuSpacer() {
        dispatch(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray tray = SwingSystemTray.this;
                synchronized (tray) {
                    synchronized (menuEntries) {
                        synchronized (menuEntries) {
                            MenuEntry menuEntry = new SwingMenuEntrySpacer(tray);
                            menuEntries.add(menuEntry);
                        }
                    }
                }
            }
        });
    }


    @Override
    protected
    void setIcon_(final File iconFile) {
        dispatch(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray tray = SwingSystemTray.this;

                // stupid java won't scale it right away, so we have to do this twice to get the correct size
                final Image trayImage = new ImageIcon(iconFile.getAbsolutePath()).getImage();
                trayImage.flush();

                synchronized (tray) {
                    if (!isActive) {
                        // here we init. everything
                        isActive = true;

                        menu = new SwingSystemTrayMenuPopup();
                        trayIcon = new TrayIcon(trayImage);

                        // appindicators don't support this, so we cater to the lowest common denominator
                        // trayIcon.setToolTip(SwingSystemTray.this.appName);

                        trayIcon.addMouseListener(new MouseAdapter() {
                            @Override
                            public
                            void mousePressed(MouseEvent e) {
                                Dimension size = menu.getPreferredSize();

                                Point point = e.getPoint();
                                Rectangle bounds = ScreenUtil.getScreenBoundsAt(point);

                                int x = point.x;
                                int y = point.y;

                                if (y < bounds.y) {
                                    y = bounds.y;
                                }
                                else if (y + size.height > bounds.y + bounds.height) {
                                    // our menu cannot have the top-edge snap to the mouse
                                    // so we make the bottom-edge snap to the mouse
                                    y -= size.height; // snap to edge of mouse
                                }

                                if (x < bounds.x) {
                                    x = bounds.x;
                                }
                                else if (x + size.width > bounds.x + bounds.width) {
                                    // our menu cannot have the left-edge snap to the mouse
                                    // so we make the right-edge snap to the mouse
                                    x -= size.width; // snap to edge of mouse
                                }

                                // voodoo to get this to popup to have the correct parent
                                // from: http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6285881
                                menu.setInvoker(menu);
                                menu.setLocation(x, y);
                                menu.setVisible(true);
                                menu.setFocusable(true);
                                menu.requestFocusInWindow();
                            }
                        });

                        try {
                            SwingSystemTray.this.tray.add(trayIcon);
                        } catch (AWTException e) {
                            logger.error("TrayIcon could not be added.", e);
                        }
                    } else {
                        tray.trayIcon.setImage(trayImage);
                    }
                }
            }
        });
    }

    /**
     * Will add a new menu entry, or update one if it already exists
     */
    protected
    void addMenuEntry_(final String menuText, final File imagePath, final SystemTrayMenuAction callback) {
        if (menuText == null) {
            throw new NullPointerException("Menu text cannot be null");
        }

        dispatch(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray tray = SwingSystemTray.this;
                synchronized (tray) {
                    synchronized (menuEntries) {
                        MenuEntry menuEntry = getMenuEntry(menuText);

                        if (menuEntry != null) {
                            throw new IllegalArgumentException("Menu entry already exists for given label '" + menuText + "'");
                        }
                        else {
                            menuEntry = new SwingMenuEntryItem(menuText, imagePath, callback, tray);
                            menuEntries.add(menuEntry);
                        }
                    }
                }
            }
        });
    }
}