/*
* Copyright 2000-2015 JetBrains s.r.o.
*
* 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 com.intellij.ide;
import com.intellij.openapi.diagnostic.Logger;
import sun.awt.DisplayChangedListener;
import java.awt.*;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
public class DisplayChangeDetector {
private static final Logger LOG = Logger.getInstance(DisplayChangeDetector.class);
private static final DisplayChangeDetector INSTANCE = new DisplayChangeDetector();
public static DisplayChangeDetector getInstance() {
return INSTANCE;
}
@SuppressWarnings("FieldCanBeLocal") // we need to keep a strong reference to this listener, as GraphicsEnvironment keeps only weak references to them
private final DisplayChangeHandler myHandler = new DisplayChangeHandler();
private final List<Listener> myListeners = new CopyOnWriteArrayList<Listener>();
private DisplayChangeDetector() {
try {
GraphicsEnvironment env = GraphicsEnvironment.getLocalGraphicsEnvironment();
env.getScreenDevices(); // init
Class<?> aClass = Class.forName("sun.awt.DisplayChangedListener"); // might be absent
if (aClass.isInstance(env)) { // Headless env does not implement sun.awt.DisplayChangedListener (and lacks addDisplayChangedListener)
env.getClass()
.getMethod("addDisplayChangedListener", new Class[]{aClass})
.invoke(env, myHandler);
}
}
catch (HeadlessException ignored) {}
catch (Throwable t) {
LOG.error("Cannot setup display change listener", t);
}
}
public void addListener(Listener listener) {
myListeners.add(listener);
}
public void removeListener(Listener listener) {
myListeners.remove(listener);
}
public interface Listener {
void displayChanged();
}
private class DisplayChangeHandler implements DisplayChangedListener {
@Override
public void displayChanged() {
runActions();
}
@Override
public void paletteChanged() {
runActions();
}
private void runActions() {
for (Listener listener : myListeners) {
listener.displayChanged();
}
}
}
}