/*
* Copyright 2000-2016 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.ui.components.panels;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.util.ui.JBInsets;
import org.jetbrains.annotations.NotNull;
import javax.swing.JPanel;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager2;
import java.awt.Rectangle;
/**
* This class is intended to lay out only one visible component.
* It takes into account not only a minimum size of a component,
* but also its maximum size. This class uses a component alignment
* to lay out a component whose maximum size less than a container size.
*
* @author Sergey.Malenkov
* @see Component#getAlignmentX
* @see Component#getAlignmentY
*/
public class StatelessCardLayout implements LayoutManager2 {
public static final StatelessCardLayout INSTANCE = new StatelessCardLayout();
/**
* Creates a simple panel with this layout manager and the specified component.
*
* @param component a component to add if necessary
* @return new panel with this layout manager and the specified component
* @see Wrapper
*/
@NotNull
public static JPanel wrap(Component component) {
JPanel panel = new JPanel(INSTANCE);
if (component != null) panel.add(component);
panel.setOpaque(false);
return panel;
}
/**
* Shows the specified component if necessary and
* hides other components in the same container.
*
* @param visible a component to show
*/
public static void show(Component visible) {
if (visible != null && !visible.isVisible()) {
Container container = visible.getParent();
if (container != null) {
synchronized (container.getTreeLock()) {
for (Component component : container.getComponents()) {
component.setVisible(component == visible);
}
}
}
}
}
private static Component getComponent(Container container) {
synchronized (container.getTreeLock()) {
for (Component component : container.getComponents()) {
if (component.isVisible()) return component;
}
}
return null;
}
private static Dimension getSize(Container container, Dimension size) {
Insets insets = container.getInsets();
if (insets != null) {
int width = size.width + insets.left + insets.right;
if (size.width < width) size.width = width;
int height = size.height + insets.top + insets.bottom;
if (size.height < height) size.height = height;
}
return size;
}
@Override
public void addLayoutComponent(String name, Component component) {
addLayoutComponent(component, name);
}
@Override
public void addLayoutComponent(Component component, Object constraints) {
if (constraints != null) throw new IllegalArgumentException("unsupported constraints: " + constraints);
Container container = component.getParent();
component.setVisible(container != null && 0 < container.getComponentCount());
}
@Override
public void removeLayoutComponent(Component component) {
}
@Override
public void invalidateLayout(Container container) {
}
@Override
public float getLayoutAlignmentX(Container container) {
Component component = getComponent(container);
return component != null ? component.getAlignmentX() : Component.CENTER_ALIGNMENT;
}
@Override
public float getLayoutAlignmentY(Container container) {
Component component = getComponent(container);
return component != null ? component.getAlignmentY() : Component.CENTER_ALIGNMENT;
}
@Override
public Dimension preferredLayoutSize(Container container) {
Component component = getComponent(container);
return getSize(container, component != null ? component.getPreferredSize() : new Dimension());
}
@Override
public Dimension minimumLayoutSize(Container container) {
Component component = getComponent(container);
return getSize(container, component != null ? component.getMinimumSize() : new Dimension());
}
@Override
public Dimension maximumLayoutSize(Container container) {
Component component = getComponent(container);
return getSize(container, component != null ? component.getMaximumSize() : new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE));
}
@Override
public void layoutContainer(Container container) {
synchronized (container.getTreeLock()) {
boolean logged = false;
boolean updated = false;
for (Component component : container.getComponents()) {
if (component.isVisible()) {
if (!updated) {
updated = true;
Dimension min = component.getMinimumSize();
Dimension max = component.getMaximumSize();
if (max.height < min.height) max.height = min.height;
Rectangle bounds = new Rectangle(container.getWidth(), container.getHeight());
JBInsets.removeFrom(bounds, container.getInsets());
if (max.width < min.width) max.width = min.width;
if (bounds.width > max.width) {
bounds.x += (int)(.5f + (bounds.width - max.width) * component.getAlignmentX());
bounds.width = max.width;
}
else if (bounds.width < min.width) {
bounds.x += (int)(.5f + (bounds.width - min.width) * component.getAlignmentX());
bounds.width = min.width;
}
if (max.height < min.height) max.height = min.height;
if (bounds.height > max.height) {
bounds.y += (int)(.5f + (bounds.height - max.height) * component.getAlignmentY());
bounds.height = max.height;
}
else if (bounds.height < min.height) {
bounds.y += (int)(.5f + (bounds.height - min.height) * component.getAlignmentY());
bounds.height = min.height;
}
component.setBounds(bounds);
}
else {
component.setVisible(false);
if (!logged) {
logged = true;
Logger.getInstance(StatelessCardLayout.class).warn("too many visible components");
}
}
}
}
}
}
}