/*
* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores
* CA 94065 USA or visit www.oracle.com if you need additional information or
* have any questions.
*/
package com.codename1.ui;
import com.codename1.ui.geom.Dimension;
import com.codename1.ui.geom.Rectangle;
/**
* A peer component is essentially a "dummy" Codename One component used to calculate the position
* of the actual native platform specific component. The behavior of a peer component is
* very platform specific, it is meant for platforms where a native component can be
* integrated with a Codename One component.
* Codename One features such as glass pane, z-ordering, dialogs & menus might not work
* as expected in all situations where peer components are involved. E.g. a peer component
* might hide itself when a menu/dialog is shown and recreate itself when it is hidden/disposed.
*
* @author Shai Almog
*/
public class PeerComponent extends Component {
private Object nativePeer;
private Rectangle lastPos = new Rectangle(-1, -1, -1, -1);
private Image peerImage;
/**
* This constructor is used by the platform implementation to create instances
* of this class use the static create method.
*
* @param nativePeer the native platform specific peer component.
*/
protected PeerComponent(Object nativePeer) {
this.nativePeer = nativePeer;
}
/**
* The peer image is drawn when the component doesn't exist or during transition
* a placeholder image can be placed in the beginning to show something while
* the peer is being created asynchronously. This image might be replaced by
* an internal image representing the actual content of the peer
* @return an image
*/
protected Image getPeerImage() {
if(peerImage == null) {
peerImage = generatePeerImage();
}
return peerImage;
}
/**
* The native implementation should implement this method to generate a native peer
* image representing the component
* @return a screenshot of the component
*/
protected Image generatePeerImage() {
return null;
}
/**
* The peer image is drawn when the component doesn't exist or during transition
* a placeholder image can be placed in the beginning to show something while
* the peer is being created asynchronously. This image might be replaced by
* an internal image representing the actual content of the peer
*
* @param i the peer image
*/
protected void setPeerImage(Image i) {
peerImage = i;
}
/**
* Subclasses should return true here if the peer image should be rendered instead of the actual peer
* @return true to render the peer image
*/
protected boolean shouldRenderPeerImage() {
return false;
}
/**
* Use this method to encapsulate a native UI object
*
* @param nativePeer the native platform specific peer component.
*/
public static PeerComponent create(Object nativePeer) {
if(nativePeer == null) {
return null;
}
return Display.impl.createNativePeer(nativePeer);
}
/**
* Returns the native peer instance
*
* @return the native peer
*/
public Object getNativePeer() {
return nativePeer;
}
void setNativePeer(Object nativePeer) {
this.nativePeer = nativePeer;
}
/**
* {@inheritDoc}
*/
public boolean animate() {
return false;
}
/**
* {@inheritDoc}
*/
protected Dimension calcPreferredSize() {
return super.calcPreferredSize();
}
/**
* {@inheritDoc}
*/
protected Dimension calcScrollSize() {
return super.calcScrollSize();
}
/**
* {@inheritDoc}
*/
protected void deinitialize() {
Form.activePeerCount--;
super.deinitialize();
}
/**
* {@inheritDoc}
*/
protected void fireClicked() {
}
/**
* {@inheritDoc}
*/
protected void focusGained() {
super.focusGained();
}
/**
* {@inheritDoc}
*/
protected void focusLost() {
super.focusLost();
}
/**
* {@inheritDoc}
*/
public boolean handlesInput() {
return super.handlesInput();
}
/**
* {@inheritDoc}
*/
protected void initComponent() {
Form.activePeerCount++;
super.initComponent();
}
/**
* {@inheritDoc}
*/
public void keyPressed(int keyCode) {
}
/**
* {@inheritDoc}
*/
public void keyReleased(int keyCode) {
}
/**
* {@inheritDoc}
*/
public void keyRepeated(int keyCode) {
}
/**
* {@inheritDoc}
*/
public void paint(Graphics g) {
onPositionSizeChangeImpl();
if(shouldRenderPeerImage() && getWidth() > 0 && getHeight() > 0) {
Image img = getPeerImage();
if(img != null) {
g.drawImage(img, getX(), getY(), getWidth(), getHeight());
}
} else {
super.paint(g);
g.drawPeerComponent(this);
}
}
private void onPositionSizeChangeImpl() {
if(isInitialized() && getWidth() > 0 && getHeight() > 0) {
int scrollX = getScrollX();
int scrollY = getScrollY();
int x = getAbsoluteX() + scrollX;
int y = getAbsoluteY() + scrollY;
if(x != lastPos.getX() || y != lastPos.getY() || getWidth() != lastPos.getSize().getWidth() || getHeight() != lastPos.getSize().getHeight()) {
lastPos.setX(x);
lastPos.setY(y);
lastPos.getSize().setWidth(getWidth());
lastPos.getSize().setHeight(getHeight());
onPositionSizeChange();
}
}
}
/**
* {@inheritDoc}
*/
void onParentPositionChange() {
onPositionSizeChangeImpl();
}
/**
* {@inheritDoc}
*/
protected void paintBackground(Graphics g) {
}
/**
* {@inheritDoc}
*/
public void paintBackgrounds(Graphics g) {
}
/**
* {@inheritDoc}
*/
protected void paintBorder(Graphics g) {
}
/**
* {@inheritDoc}
*/
protected void paintScrollbarX(Graphics g) {
}
/**
* {@inheritDoc}
*/
protected void paintScrollbarY(Graphics g) {
}
/**
* {@inheritDoc}
*/
protected void paintScrollbars(Graphics g) {
}
/**
* {@inheritDoc}
*/
public void pointerDragged(int[] x, int[] y) {
}
/**
* {@inheritDoc}
*/
public void pointerDragged(int x, int y) {
}
/**
* {@inheritDoc}
*/
public void pointerHover(int[] x, int[] y) {
}
/**
* {@inheritDoc}
*/
public void pointerHoverReleased(int[] x, int[] y) {
}
/**
* {@inheritDoc}
*/
public void pointerPressed(int[] x, int[] y) {
}
/**
* {@inheritDoc}
*/
public void pointerPressed(int x, int y) {
}
/**
* {@inheritDoc}
*/
public void pointerReleased(int[] x, int[] y) {
}
/**
* {@inheritDoc}
*/
public void pointerReleased(int x, int y) {
}
/**
* Updates the size of the component from the native widget
*/
public void invalidate() {
setShouldCalcPreferredSize(true);
getComponentForm().revalidate();
}
/**
* Callback useful for sublclasses that need to track the change in size/position
* of the component (notice that this might be invoked too many times for a single change)!
*/
protected void onPositionSizeChange() {
}
/**
* An optional callback for peers indicating that the peer is now rendered as part of
* a transition or some other state and is thus not truly visible. In this case the
* peer should either make itself invisible or render itself as an image instead of
* natively
*
* @param l true to enable lightweight mode, false to disable it
*/
protected void setLightweightMode(boolean l) {
}
}