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showimg-example.html

Last change on this file was 190, checked in by rudi, 14 years ago
reference documentation added
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[190]	1	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
	2	<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/examples/showimg/showimg.doc:4 -->
	3	<html>
	4	<head>
	5	<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
	6	<title>Show Image</title>
	7	<style type="text/css"><!--
	8	fn { margin-left: 1cm; text-indent: -1cm; }
	9	a:link { color: #004faf; text-decoration: none }
	10	a:visited { color: #672967; text-decoration: none }
	11	body { background: #ffffff; color: black; }
	12	--></style>
	13	</head>
	14	<body>
	15
	16	<table border="0" cellpadding="0" cellspacing="0" width="100%">
	17	<tr bgcolor="#E5E5E5">
	18	<td valign=center>
	19	<a href="index.html">
	20	<font color="#004faf">Home</font></a>
	21	\| <a href="classes.html">
	22	<font color="#004faf">All Classes</font></a>
	23	\| <a href="mainclasses.html">
	24	<font color="#004faf">Main Classes</font></a>
	25	\| <a href="annotated.html">
	26	<font color="#004faf">Annotated</font></a>
	27	\| <a href="groups.html">
	28	<font color="#004faf">Grouped Classes</font></a>
	29	\| <a href="functions.html">
	30	<font color="#004faf">Functions</font></a>
	31	</td>
	32	<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Show Image</h1>
	33
	34
	35	<p>
	36	This example reads and displays an image in any supported image
	37	format (GIF, BMP, PPM, XMP, etc.).
	38	<p> <hr>
	39	<p> Header file:
	40	<p> <pre>/****************************************************************************
	41	** $Id: showimg-example.html 2051 2007-02-21 10:04:20Z chehrlic $
	42	**
	43	** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved.
	44	**
	45	** This file is part of an example program for Qt. This example
	46	** program may be used, distributed and modified without limitation.
	47	**
	48	*****************************************************************************/
	49
	50	#ifndef SHOWIMG_H
	51	#define SHOWIMG_H
	52
	53	#include <<a href="qwidget-h.html">qwidget.h</a>>
	54	#include <<a href="qimage-h.html">qimage.h</a>>
	55
	56
	57	class QLabel;
	58	class QMenuBar;
	59	class QPopupMenu;
	60
	61	class ImageViewer : public <a href="qwidget.html">QWidget</a>
	62	{
	63	<a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a>
	64	public:
	65	ImageViewer( <a href="qwidget.html">QWidget</a> parent=0, const char name=0, int wFlags=0 );
	66	~ImageViewer();
	67	bool loadImage( const <a href="qstring.html">QString</a>& );
	68	protected:
	69	void paintEvent( <a href="qpaintevent.html">QPaintEvent</a> * );
	70	void resizeEvent( <a href="qresizeevent.html">QResizeEvent</a> * );
	71	void mousePressEvent( <a href="qmouseevent.html">QMouseEvent</a> * );
	72	void mouseReleaseEvent( <a href="qmouseevent.html">QMouseEvent</a> * );
	73	void mouseMoveEvent( <a href="qmouseevent.html">QMouseEvent</a> * );
	74
	75	private:
	76	void scale();
	77	int conversion_flags;
	78	bool smooth() const;
	79	bool useColorContext() const;
	80	int alloc_context;
	81	bool convertEvent( <a href="qmouseevent.html">QMouseEvent</a>* e, int& x, int& y );
	82	<a href="qstring.html">QString</a> filename;
	83	<a href="qimage.html">QImage</a> image; // the loaded image
	84	<a href="qpixmap.html">QPixmap</a> pm; // the converted pixmap
	85	<a href="qpixmap.html">QPixmap</a> pmScaled; // the scaled pixmap
	86
	87	<a href="qmenubar.html">QMenuBar</a> *menubar;
	88	<a href="qpopupmenu.html">QPopupMenu</a> *file;
	89	<a href="qpopupmenu.html">QPopupMenu</a> *saveimage;
	90	<a href="qpopupmenu.html">QPopupMenu</a> *savepixmap;
	91	<a href="qpopupmenu.html">QPopupMenu</a> *edit;
	92	<a href="qpopupmenu.html">QPopupMenu</a> *options;
	93
	94	<a href="qwidget.html">QWidget</a> *helpmsg;
	95	<a href="qlabel.html">QLabel</a> *status;
	96	int si, sp, ac, co, mo, fd, bd, // Menu item ids
	97	td, ta, ba, fa, au, ad, dd,
	98	ss, cc, t1, t8, t32;
	99	void updateStatus();
	100	void setMenuItemFlags();
	101	bool reconvertImage();
	102	int pickx, picky;
	103	int clickx, clicky;
	104	bool may_be_other;
	105	static ImageViewer* other;
	106	void setImage(const <a href="qimage.html">QImage</a>& newimage);
	107
	108	private slots:
	109	void to1Bit();
	110	void to8Bit();
	111	void to32Bit();
	112	void toBitDepth(int);
	113
	114	void copy();
	115	void paste();
	116
	117	void hFlip();
	118	void vFlip();
	119	void rot180();
	120
	121	void editText();
	122
	123	void newWindow();
	124	void openFile();
	125	void saveImage(int);
	126	void savePixmap(int);
	127	void giveHelp();
	128	void doOption(int);
	129	void copyFrom(ImageViewer*);
	130	};
	131
	132
	133	#endif // SHOWIMG_H
	134	</pre>
	135
	136	<p> <hr>
	137	<p> Implementation:
	138	<p> <pre>/****************************************************************************
	139	** $Id: showimg-example.html 2051 2007-02-21 10:04:20Z chehrlic $
	140	**
	141	** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved.
	142	**
	143	** This file is part of an example program for Qt. This example
	144	** program may be used, distributed and modified without limitation.
	145	**
	146	*****************************************************************************/
	147
	148	#include "showimg.h"
	149	#include "imagetexteditor.h"
	150	#include <<a href="qmenubar-h.html">qmenubar.h</a>>
	151	#include <<a href="qfiledialog-h.html">qfiledialog.h</a>>
	152	#include <<a href="qmessagebox-h.html">qmessagebox.h</a>>
	153	#include <<a href="qpopupmenu-h.html">qpopupmenu.h</a>>
	154	#include <<a href="qlabel-h.html">qlabel.h</a>>
	155	#include <<a href="qpainter-h.html">qpainter.h</a>>
	156	#include <<a href="qapplication-h.html">qapplication.h</a>>
	157	#include <<a href="qclipboard-h.html">qclipboard.h</a>>
	158
	159
	160	/*
	161	In the constructor, we just pass the standard parameters on to
	162	QWidget.
	163
	164	The menu uses a single slot to simplify the process of adding
	165	more items to the options menu.
	166	*/
	167	<a name="f405"></a>ImageViewer::ImageViewer( <a href="qwidget.html">QWidget</a> parent, const char name, int wFlags )
	168	: <a href="qwidget.html">QWidget</a>( parent, name, wFlags ),
	169	conversion_flags( PreferDither ),
	170	helpmsg( 0 )
	171	{
	172	pickx = -1;
	173	picky = -1;
	174	clickx = -1;
	175	clicky = -1;
	176	alloc_context = 0;
	177
	178	menubar = new <a href="qmenubar.html">QMenuBar</a>(this);
	179	<a name="x1326"></a> menubar-><a href="qmenubar.html#setSeparator">setSeparator</a>( QMenuBar::InWindowsStyle );
	180
	181	<a name="x1323"></a> <a href="qstrlist.html">QStrList</a> fmt = QImage::<a href="qimage.html#outputFormats">outputFormats</a>();
	182	saveimage = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	183	savepixmap = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	184	<a name="x1344"></a><a name="x1343"></a> for (const char* f = fmt.<a href="qptrlist.html#first">first</a>(); f; f = fmt.<a href="qptrlist.html#next">next</a>()) {
	185	<a name="x1327"></a> saveimage-><a href="qmenudata.html#insertItem">insertItem</a>( f );
	186	savepixmap-><a href="qmenudata.html#insertItem">insertItem</a>( f );
	187	}
	188	<a name="x1341"></a> <a href="qobject.html#connect">connect</a>( saveimage, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(saveImage(int)) );
	189	<a href="qobject.html#connect">connect</a>( savepixmap, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(savePixmap(int)) );
	190
	191	file = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	192	menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&File", file );
	193	file-><a href="qmenudata.html#insertItem">insertItem</a>( "&New window", this, SLOT(newWindow()), CTRL+Key_N );
	194	file-><a href="qmenudata.html#insertItem">insertItem</a>( "&Open...", this, SLOT(openFile()), CTRL+Key_O );
	195	si = file-><a href="qmenudata.html#insertItem">insertItem</a>( "Save image", saveimage );
	196	sp = file-><a href="qmenudata.html#insertItem">insertItem</a>( "Save pixmap", savepixmap );
	197	<a name="x1328"></a> file-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	198	file-><a href="qmenudata.html#insertItem">insertItem</a>( "E&xit", qApp, SLOT(<a href="qapplication.html#quit">quit</a>()), CTRL+Key_Q );
	199
	200	edit = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	201	menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Edit", edit );
	202	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Copy", this, SLOT(copy()), CTRL+Key_C);
	203	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Paste", this, SLOT(paste()), CTRL+Key_V);
	204	edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	205	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Horizontal flip", this, SLOT(hFlip()), ALT+Key_H);
	206	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Vertical flip", this, SLOT(vFlip()), ALT+Key_V);
	207	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Rotate 180", this, SLOT(rot180()), ALT+Key_R);
	208	edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	209	edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Text...", this, SLOT(editText()));
	210	edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	211	t1 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &1 bit", this, SLOT(to1Bit()) );
	212	t8 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &8 bit", this, SLOT(to8Bit()) );
	213	t32 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &32 bit", this, SLOT(to32Bit()) );
	214
	215	options = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	216	menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Options", options );
	217	ac = options-><a href="qmenudata.html#insertItem">insertItem</a>( "AutoColor" );
	218	co = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ColorOnly" );
	219	mo = options-><a href="qmenudata.html#insertItem">insertItem</a>( "MonoOnly" );
	220	options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	221	fd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "DiffuseDither" );
	222	bd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "OrderedDither" );
	223	td = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ThresholdDither" );
	224	options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	225	ta = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ThresholdAlphaDither" );
	226	ba = options-><a href="qmenudata.html#insertItem">insertItem</a>( "OrderedAlphaDither" );
	227	fa = options-><a href="qmenudata.html#insertItem">insertItem</a>( "DiffuseAlphaDither" );
	228	options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	229	ad = options-><a href="qmenudata.html#insertItem">insertItem</a>( "PreferDither" );
	230	dd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "AvoidDither" );
	231	options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	232	ss = options-><a href="qmenudata.html#insertItem">insertItem</a>( "Smooth scaling" );
	233	cc = options-><a href="qmenudata.html#insertItem">insertItem</a>( "Use color context" );
	234	<a name="x1309"></a> if ( QApplication::<a href="qapplication.html#colorSpec">colorSpec</a>() == QApplication::ManyColor )
	235	<a name="x1331"></a> options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( cc, FALSE );
	236	<a name="x1342"></a> options-><a href="qpopupmenu.html#setCheckable">setCheckable</a>( TRUE );
	237	setMenuItemFlags();
	238
	239	menubar-><a href="qmenudata.html#insertSeparator">insertSeparator</a>();
	240
	241	<a href="qpopupmenu.html">QPopupMenu</a>* help = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar );
	242	menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Help", help );
	243	help-><a href="qmenudata.html#insertItem">insertItem</a>( "Help!", this, SLOT(giveHelp()), CTRL+Key_H );
	244
	245	<a href="qobject.html#connect">connect</a>( options, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(doOption(int)) );
	246
	247	status = new <a href="qlabel.html">QLabel</a>(this);
	248	status-><a href="qframe.html#setFrameStyle">setFrameStyle</a>( QFrame::WinPanel \| QFrame::Sunken );
	249	<a name="x1354"></a> status-><a href="qwidget.html#setFixedHeight">setFixedHeight</a>( <a href="qwidget.html#fontMetrics">fontMetrics</a>().height() + 4 );
	250
	251	<a href="qwidget.html#setMouseTracking">setMouseTracking</a>( TRUE );
	252	}
	253
	254	ImageViewer::~ImageViewer()
	255	{
	256	if ( alloc_context )
	257	<a name="x1313"></a> QColor::<a href="qcolor.html#destroyAllocContext">destroyAllocContext</a>( alloc_context );
	258	if ( other == this )
	259	other = 0;
	260	}
	261
	262	/*
	263	This function modifies the conversion_flags when an options menu item
	264	is selected, then ensures all menu items are up to date, and reconverts
	265	the image if possibly necessary.
	266	*/
	267	void <a name="f406"></a>ImageViewer::doOption(int item)
	268	{
	269	if ( item == ss \|\| item == cc ) {
	270	// Toggle
	271	<a name="x1329"></a> bool newbool = !options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(item);
	272	<a name="x1330"></a> options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>(item, newbool);
	273	// And reconvert...
	274	reconvertImage();
	275	<a href="qwidget.html#repaint">repaint</a>(image.hasAlphaBuffer()); // show image in widget
	276	return;
	277	}
	278
	279	if ( options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>( item ) ) return; // They are all radio buttons
	280
	281	int ocf = conversion_flags;
	282
	283	if ( item == ac ) {
	284	conversion_flags = ( conversion_flags & ~ColorMode_Mask ) \| AutoColor;
	285	} else if ( item == co ) {
	286	conversion_flags = ( conversion_flags & ~ColorMode_Mask ) \| ColorOnly;
	287	} else if ( item == mo ) {
	288	conversion_flags = ( conversion_flags & ~ColorMode_Mask ) \| MonoOnly;
	289	} else if ( item == fd ) {
	290	conversion_flags = ( conversion_flags & ~Dither_Mask ) \| DiffuseDither;
	291	} else if ( item == bd ) {
	292	conversion_flags = ( conversion_flags & ~Dither_Mask ) \| OrderedDither;
	293	} else if ( item == td ) {
	294	conversion_flags = ( conversion_flags & ~Dither_Mask ) \| ThresholdDither;
	295	} else if ( item == ta ) {
	296	conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) \| ThresholdAlphaDither;
	297	} else if ( item == fa ) {
	298	conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) \| DiffuseAlphaDither;
	299	} else if ( item == ba ) {
	300	conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) \| OrderedAlphaDither;
	301	} else if ( item == ad ) {
	302	conversion_flags = ( conversion_flags & ~DitherMode_Mask ) \| PreferDither;
	303	} else if ( item == dd ) {
	304	conversion_flags = ( conversion_flags & ~DitherMode_Mask ) \| AvoidDither;
	305	}
	306
	307	if ( ocf != conversion_flags ) {
	308	setMenuItemFlags();
	309	// And reconvert...
	310	reconvertImage();
	311	<a href="qwidget.html#repaint">repaint</a>(image.hasAlphaBuffer()); // show image in widget
	312	}
	313	}
	314
	315	/*
	316	Set the options menu to reflect the conversion_flags value.
	317	*/
	318	void <a name="f407"></a>ImageViewer::setMenuItemFlags()
	319	{
	320	// File
	321	bool valid_image = pm.size() != QSize( 0, 0 );
	322	file-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( si, valid_image );
	323	file-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( sp, valid_image );
	324
	325	// Edit
	326	edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t1, image.depth() != 1 );
	327	edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t8, image.depth() != 8 );
	328	edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t32, image.depth() != 32 );
	329
	330	// Options
	331	bool may_need_color_dithering =
	332	!valid_image
	333	\|\| image.depth() == 32 && QPixmap::<a href="qpixmap.html#defaultDepth">defaultDepth</a>() < 24;
	334	bool may_need_dithering = may_need_color_dithering
	335	\|\| image.depth() > 1 && options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(mo)
	336	\|\| image.depth() > 1 && QPixmap::<a href="qpixmap.html#defaultDepth">defaultDepth</a>() == 1;
	337	bool has_alpha_mask = !valid_image \|\| image.hasAlphaBuffer();
	338
	339	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( fd, may_need_dithering );
	340	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( bd, may_need_dithering );
	341	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( td, may_need_dithering );
	342
	343	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ta, has_alpha_mask );
	344	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( fa, has_alpha_mask );
	345	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ba, has_alpha_mask );
	346
	347	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ad, may_need_color_dithering );
	348	options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( dd, may_need_color_dithering );
	349
	350	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ac, (conversion_flags & ColorMode_Mask) == AutoColor );
	351	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( co, (conversion_flags & ColorMode_Mask) == ColorOnly );
	352	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( mo, (conversion_flags & ColorMode_Mask) == MonoOnly );
	353	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( fd, (conversion_flags & Dither_Mask) == DiffuseDither );
	354	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( bd, (conversion_flags & Dither_Mask) == OrderedDither );
	355	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( td, (conversion_flags & Dither_Mask) == ThresholdDither );
	356	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ta, (conversion_flags & AlphaDither_Mask) == ThresholdAlphaDither );
	357	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( fa, (conversion_flags & AlphaDither_Mask) == DiffuseAlphaDither );
	358	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ba, (conversion_flags & AlphaDither_Mask) == OrderedAlphaDither );
	359	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ad, (conversion_flags & DitherMode_Mask) == PreferDither );
	360	options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( dd, (conversion_flags & DitherMode_Mask) == AvoidDither );
	361	}
	362
	363	void <a name="f408"></a>ImageViewer::updateStatus()
	364	{
	365	if ( pm.size() == QSize( 0, 0 ) ) {
	366	if ( !filename.isEmpty() )
	367	status-><a href="qlabel.html#setText">setText</a>("Could not load image");
	368	else
	369	status-><a href="qlabel.html#setText">setText</a>("No image - select Open from File menu.");
	370	} else {
	371	<a href="qstring.html">QString</a> message, moremsg;
	372	message.<a href="qstring.html#sprintf">sprintf</a>("%dx%d", image.width(), image.height());
	373	if ( pm.size() != pmScaled.size() ) {
	374	moremsg.sprintf(" [%dx%d]", pmScaled.width(),
	375	pmScaled.height());
	376	message += moremsg;
	377	}
	378	moremsg.sprintf(", %d bits ", image.depth());
	379	message += moremsg;
	380	if (image.valid(pickx,picky)) {
	381	moremsg.sprintf("(%d,%d)=#%0*x ",
	382	pickx, picky,
	383	image.hasAlphaBuffer() ? 8 : 6,
	384	image.pixel(pickx,picky));
	385	message += moremsg;
	386	}
	387	if ( image.numColors() > 0 ) {
	388	if (image.valid(pickx,picky)) {
	389	moremsg.sprintf(", %d/%d colors", image.pixelIndex(pickx,picky),
	390	image.numColors());
	391	} else {
	392	moremsg.sprintf(", %d colors", image.numColors());
	393	}
	394	message += moremsg;
	395	}
	396	if ( image.hasAlphaBuffer() ) {
	397	if ( image.depth() == 8 ) {
	398	int i;
	399	bool alpha[256];
	400	int nalpha=0;
	401
	402	for (i=0; i<256; i++)
	403	alpha[i] = FALSE;
	404
	405	for (i=0; i<image.numColors(); i++) {
	406	int alevel = image.color(i) >> 24;
	407	if (!alpha[alevel]) {
	408	alpha[alevel] = TRUE;
	409	nalpha++;
	410	}
	411	}
	412	moremsg.sprintf(", %d alpha levels", nalpha);
	413	} else {
	414	// Too many pixels to bother counting.
	415	moremsg = ", 8-bit alpha channel";
	416	}
	417	message += moremsg;
	418	}
	419	status-><a href="qlabel.html#setText">setText</a>(message);
	420	}
	421	}
	422
	423	/*
	424	This function saves the image.
	425	*/
	426	void <a name="f409"></a>ImageViewer::saveImage( int item )
	427	{
	428	<a name="x1332"></a> const char* fmt = saveimage-><a href="qmenudata.html#text">text</a>(item);
	429	<a name="x1319"></a> <a href="qstring.html">QString</a> savefilename = QFileDialog::<a href="qfiledialog.html#getSaveFileName">getSaveFileName</a>(QString::null, <a href="qstring.html#QString-null">QString::null</a>,
	430	this, filename);
	431	if ( !savefilename.<a href="qstring.html#isEmpty">isEmpty</a>() )
	432	if ( !image.save( savefilename, fmt ) )
	433	<a name="x1333"></a> QMessageBox::<a href="qmessagebox.html#warning">warning</a>( this, "Save failed", "Error saving file" );
	434	}
	435
	436	/*
	437	This function saves the converted image.
	438	*/
	439	void <a name="f410"></a>ImageViewer::savePixmap( int item )
	440	{
	441	const char* fmt = savepixmap-><a href="qmenudata.html#text">text</a>(item);
	442	<a href="qstring.html">QString</a> savefilename = QFileDialog::<a href="qfiledialog.html#getSaveFileName">getSaveFileName</a>(QString::null,
	443	QString::null, this, filename);
	444	if ( !savefilename.<a href="qstring.html#isEmpty">isEmpty</a>() )
	445	if ( !pmScaled.save( savefilename, fmt ) )
	446	QMessageBox::<a href="qmessagebox.html#warning">warning</a>( this, "Save failed", "Error saving file" );
	447	}
	448
	449
	450	void <a name="f411"></a>ImageViewer::newWindow()
	451	{
	452	ImageViewer* that = new ImageViewer(0, "new window", WDestructiveClose);
	453	that->options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( that->cc, useColorContext() );
	454	that-><a href="qwidget.html#show">show</a>();
	455	}
	456
	457	/*
	458	This function is the slot for processing the Open menu item.
	459	*/
	460	void <a name="f412"></a>ImageViewer::openFile()
	461	{
	462	<a name="x1318"></a> <a href="qstring.html">QString</a> newfilename = QFileDialog::<a href="qfiledialog.html#getOpenFileName">getOpenFileName</a>( QString::null,
	463	QString::null,
	464	this );
	465	if ( !newfilename.<a href="qstring.html#isEmpty">isEmpty</a>() ) {
	466	loadImage( newfilename ) ;
	467	<a href="qwidget.html#repaint">repaint</a>(); // show image in widget
	468	}
	469	}
	470
	471	/*
	472	This function loads an image from a file and resizes the widget to
	473	exactly fit the image size. If the file was not found or the image
	474	format was unknown it will resize the widget to fit the errorText
	475	message (see above) displayed in the current font.
	476
	477	Returns TRUE if the image was successfully loaded.
	478	*/
	479
	480	bool <a name="f413"></a>ImageViewer::loadImage( const <a href="qstring.html">QString</a>& fileName )
	481	{
	482	filename = fileName;
	483	bool ok = FALSE;
	484	if ( !filename.isEmpty() ) {
	485	<a name="x1312"></a> QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time
	486	ok = image.load(filename, 0);
	487	pickx = -1;
	488	clickx = -1;
	489	if ( ok )
	490	ok = reconvertImage();
	491	if ( ok ) {
	492	<a href="qwidget.html#setCaption">setCaption</a>( filename ); // set window caption
	493	int w = pm.width();
	494	int h = pm.height();
	495
	496	const int reasonable_width = 128;
	497	if ( w < reasonable_width ) {
	498	// Integer scale up to something reasonable
	499	int multiply = ( reasonable_width + w - 1 ) / w;
	500	w *= multiply;
	501	h *= multiply;
	502	}
	503
	504	<a name="x1347"></a><a name="x1325"></a> h += menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>(w) + status-><a href="qwidget.html#height">height</a>();
	505	<a href="qwidget.html#resize">resize</a>( w, h ); // we resize to fit image
	506	} else {
	507	pm.resize(0,0); // couldn't load image
	508	<a href="qwidget.html#update">update</a>();
	509	}
	510	<a name="x1311"></a> QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor
	511	}
	512	updateStatus();
	513	setMenuItemFlags();
	514	return ok;
	515	}
	516
	517	bool <a name="f414"></a>ImageViewer::reconvertImage()
	518	{
	519	bool success = FALSE;
	520
	521	if ( image.isNull() ) return FALSE;
	522
	523	if ( alloc_context ) {
	524	QColor::<a href="qcolor.html#destroyAllocContext">destroyAllocContext</a>( alloc_context );
	525	alloc_context = 0;
	526	}
	527	if ( useColorContext() ) {
	528	<a name="x1314"></a> alloc_context = QColor::<a href="qcolor.html#enterAllocContext">enterAllocContext</a>();
	529	// Clear the image to hide flickering palette
	530	<a href="qpainter.html">QPainter</a> painter(this);
	531	<a name="x1338"></a> painter.<a href="qpainter.html#eraseRect">eraseRect</a>(0, menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ), width(), height());
	532	}
	533
	534	QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time
	535	if ( pm.convertFromImage(image, conversion_flags) )
	536	{
	537	pmScaled = QPixmap();
	538	scale();
	539	<a href="qwidget.html#resize">resize</a>( <a href="qwidget.html#width">width</a>(), height() );
	540	success = TRUE; // load successful
	541	} else {
	542	pm.resize(0,0); // couldn't load image
	543	}
	544	updateStatus();
	545	setMenuItemFlags();
	546	QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor
	547
	548	if ( useColorContext() )
	549	<a name="x1315"></a> QColor::<a href="qcolor.html#leaveAllocContext">leaveAllocContext</a>();
	550
	551	return success; // TRUE if loaded OK
	552	}
	553
	554	bool <a name="f415"></a>ImageViewer::smooth() const
	555	{
	556	return options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(ss);
	557	}
	558
	559	bool <a name="f416"></a>ImageViewer::useColorContext() const
	560	{
	561	return options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(cc);
	562	}
	563
	564	/*
	565	This functions scales the pixmap in the member variable "pm" to fit the
	566	widget size and puts the resulting pixmap in the member variable "pmScaled".
	567	*/
	568
	569	void <a name="f417"></a>ImageViewer::scale()
	570	{
	571	int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>();
	572
	573	if ( image.isNull() ) return;
	574
	575	QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time
	576	if ( <a href="qwidget.html#width">width</a>() == pm.width() && h == pm.height() )
	577	{ // no need to scale if widget
	578	pmScaled = pm; // size equals pixmap size
	579	} else {
	580	if (smooth()) {
	581	pmScaled.convertFromImage(image.smoothScale(<a href="qwidget.html#width">width</a>(), h),
	582	conversion_flags);
	583	} else {
	584	<a href="qwmatrix.html">QWMatrix</a> m; // <a href="qwmatrix.html#TransformationMode">transformation matrix</a>
	585	<a name="x1357"></a> m.<a href="qwmatrix.html#scale">scale</a>(((double)<a href="qwidget.html#width">width</a>())/pm.width(),// define scale factors
	586	((double)h)/pm.height());
	587	pmScaled = pm.xForm( m ); // create scaled pixmap
	588	}
	589	}
	590	QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor
	591	}
	592
	593	/*
	594	The resize event handler, if a valid pixmap was loaded it will call
	595	scale() to fit the pixmap to the new widget size.
	596	*/
	597
	598	<a name="x1353"></a>void ImageViewer::<a href="qwidget.html#resizeEvent">resizeEvent</a>( <a href="qresizeevent.html">QResizeEvent</a> * )
	599	{
	600	<a name="x1355"></a> status-><a href="qwidget.html#setGeometry">setGeometry</a>(0, height() - status-><a href="qwidget.html#height">height</a>(),
	601	<a href="qwidget.html#width">width</a>(), status-><a href="qwidget.html#height">height</a>());
	602
	603	if ( pm.size() == QSize( 0, 0 ) ) // we couldn't load the image
	604	return;
	605
	606	int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>();
	607	if ( <a href="qwidget.html#width">width</a>() != pmScaled.width() \|\| h != pmScaled.height())
	608	{ // if new size,
	609	scale(); // scale pmScaled to window
	610	updateStatus();
	611	}
	612	if ( image.hasAlphaBuffer() )
	613	<a href="qwidget.html#erase">erase</a>();
	614	}
	615
	616	bool <a name="f418"></a>ImageViewer::convertEvent( <a href="qmouseevent.html">QMouseEvent</a>* e, int& x, int& y)
	617	{
	618	if ( pm.size() != QSize( 0, 0 ) ) {
	619	int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>();
	620	<a name="x1335"></a> int nx = e-><a href="qmouseevent.html#x">x</a>() * image.width() / width();
	621	<a name="x1336"></a> int ny = (e-><a href="qmouseevent.html#y">y</a>()-menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() )) * image.height() / h;
	622	if (nx != x \|\| ny != y ) {
	623	x = nx;
	624	y = ny;
	625	updateStatus();
	626	return TRUE;
	627	}
	628	}
	629	return FALSE;
	630	}
	631
	632	void ImageViewer::<a href="qwidget.html#mousePressEvent">mousePressEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> *e )
	633	{
	634	may_be_other = convertEvent(e, clickx, clicky);
	635	}
	636
	637	<a name="x1350"></a>void ImageViewer::<a href="qwidget.html#mouseReleaseEvent">mouseReleaseEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> * )
	638	{
	639	if ( may_be_other )
	640	other = this;
	641	}
	642
	643	/*
	644	Record the pixel position of interest.
	645	*/
	646	void ImageViewer::<a href="qwidget.html#mouseMoveEvent">mouseMoveEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> *e )
	647	{
	648	if (convertEvent(e,pickx,picky)) {
	649	updateStatus();
	650	<a name="x1334"></a> if ((e-><a href="qmouseevent.html#state">state</a>()&LeftButton)) {
	651	may_be_other = FALSE;
	652	if ( clickx >= 0 && other) {
	653	copyFrom(other);
	654	}
	655	}
	656	}
	657	}
	658
	659	/*
	660	Draws the portion of the scaled pixmap that needs to be updated or prints
	661	an error message if no legal pixmap has been loaded.
	662	*/
	663
	664	void ImageViewer::<a href="qwidget.html#paintEvent">paintEvent</a>( <a href="qpaintevent.html">QPaintEvent</a> *e )
	665	{
	666	if ( pm.size() != QSize( 0, 0 ) ) { // is an image loaded?
	667	<a href="qpainter.html">QPainter</a> painter(this);
	668	<a name="x1340"></a><a name="x1339"></a> painter.<a href="qpainter.html#setClipRect">setClipRect</a>(e-><a href="qpaintevent.html#rect">rect</a>());
	669	<a name="x1337"></a> painter.<a href="qpainter.html#drawPixmap">drawPixmap</a>(0, menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ), pmScaled);
	670	}
	671	}
	672
	673
	674	/*
	675	Explain anything that might be confusing.
	676	*/
	677	void <a name="f419"></a>ImageViewer::giveHelp()
	678	{
	679	if (!helpmsg) {
	680	<a href="qstring.html">QString</a> helptext =
	681	"<b>Usage:</b> <tt>showimg [-m] <i>filename ...</i></tt>"
	682	"<blockquote>"
	683	"<tt>-m</tt> - use <i>ManyColor</i> color spec"
	684	"</blockquote>"
	685	"<p>Supported input formats:"
	686	"<blockquote>";
	687	<a name="x1321"></a> helptext += QImage::<a href="qimage.html#inputFormatList">inputFormatList</a>().join(", ");
	688	helptext += "</blockquote>";
	689
	690	helpmsg = new <a href="qmessagebox.html">QMessageBox</a>( "Help", helptext,
	691	QMessageBox::Information, QMessageBox::Ok, 0, 0, 0, 0, FALSE );
	692	}
	693	<a name="x1317"></a> helpmsg-><a href="qdialog.html#show">show</a>();
	694	<a name="x1352"></a> helpmsg-><a href="qwidget.html#raise">raise</a>();
	695	}
	696
	697	void <a name="f420"></a>ImageViewer::copyFrom(ImageViewer* s)
	698	{
	699	if ( clickx >= 0 ) {
	700	int dx = clickx;
	701	int dy = clicky;
	702	int sx = s->clickx;
	703	int sy = s->clicky;
	704	int sw = QABS(clickx - pickx)+1;
	705	int sh = QABS(clicky - picky)+1;
	706	if ( clickx > pickx ) {
	707	dx = pickx;
	708	sx -= sw-1;
	709	}
	710	if ( clicky > picky ) {
	711	dy = picky;
	712	sy -= sh-1;
	713	}
	714	<a href="qimage.html#bitBlt">bitBlt</a>( &image, dx, dy, &s->image, sx, sy, sw, sh );
	715	reconvertImage();
	716	<a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() );
	717	}
	718	}
	719	ImageViewer* ImageViewer::other = 0;
	720
	721	void <a name="f421"></a>ImageViewer::hFlip()
	722	{
	723	setImage(image.mirror(TRUE,FALSE));
	724	}
	725
	726	void <a name="f422"></a>ImageViewer::vFlip()
	727	{
	728	setImage(image.mirror(FALSE,TRUE));
	729	}
	730
	731	void <a name="f423"></a>ImageViewer::rot180()
	732	{
	733	setImage(image.mirror(TRUE,TRUE));
	734	}
	735
	736	void <a name="f424"></a>ImageViewer::copy()
	737	{
	738	#ifndef QT_NO_MIMECLIPBOARD
	739	<a name="x1308"></a> QApplication::<a href="qapplication.html#clipboard">clipboard</a>()->setImage(image); // Less information loss
	740	#endif
	741	}
	742
	743	void <a name="f425"></a>ImageViewer::paste()
	744	{
	745	#ifndef QT_NO_MIMECLIPBOARD
	746	<a href="qimage.html">QImage</a> p = QApplication::<a href="qapplication.html#clipboard">clipboard</a>()->image();
	747	<a name="x1322"></a> if ( !p.<a href="qimage.html#isNull">isNull</a>() ) {
	748	filename = "pasted";
	749	setImage(p);
	750	}
	751	#endif
	752	}
	753
	754	void <a name="f426"></a>ImageViewer::setImage(const <a href="qimage.html">QImage</a>& newimage)
	755	{
	756	image = newimage;
	757
	758	pickx = -1;
	759	clickx = -1;
	760	<a href="qwidget.html#setCaption">setCaption</a>( filename ); // set window caption
	761	int w = image.width();
	762	int h = image.height();
	763	if ( !w )
	764	return;
	765
	766	const int reasonable_width = 128;
	767	if ( w < reasonable_width ) {
	768	// Integer scale up to something reasonable
	769	int multiply = ( reasonable_width + w - 1 ) / w;
	770	w *= multiply;
	771	h *= multiply;
	772	}
	773
	774	h += menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>(w) + status-><a href="qwidget.html#height">height</a>();
	775	<a href="qwidget.html#resize">resize</a>( w, h ); // we resize to fit image
	776
	777	reconvertImage();
	778	<a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() );
	779
	780	updateStatus();
	781	setMenuItemFlags();
	782	}
	783
	784	void <a name="f427"></a>ImageViewer::editText()
	785	{
	786	ImageTextEditor editor(image,this);
	787	editor.<a href="qdialog.html#exec">exec</a>();
	788	}
	789
	790	void <a name="f428"></a>ImageViewer::to1Bit()
	791	{
	792	toBitDepth(1);
	793	}
	794
	795	void <a name="f429"></a>ImageViewer::to8Bit()
	796	{
	797	toBitDepth(8);
	798	}
	799
	800	void <a name="f430"></a>ImageViewer::to32Bit()
	801	{
	802	toBitDepth(32);
	803	}
	804
	805	void <a name="f431"></a>ImageViewer::toBitDepth(int d)
	806	{
	807	image = image.convertDepth(d);
	808	reconvertImage();
	809	<a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() );
	810	}
	811	</pre>
	812
	813	<p> <hr>
	814	<p> Main:
	815	<p> <pre>/****************************************************************************
	816	** $Id: showimg-example.html 2051 2007-02-21 10:04:20Z chehrlic $
	817	**
	818	** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved.
	819	**
	820	** This file is part of an example program for Qt. This example
	821	** program may be used, distributed and modified without limitation.
	822	**
	823	*****************************************************************************/
	824
	825	#include "showimg.h"
	826	#include "imagefip.h"
	827	#include <<a href="qapplication-h.html">qapplication.h</a>>
	828	#include <<a href="qimage-h.html">qimage.h</a>>
	829
	830	int main( int argc, char **argv )
	831	{
	832	if ( argc > 1 && QString(argv[1]) == "-m" ) {
	833	<a name="x1361"></a> QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::ManyColor );
	834	argc--;
	835	argv++;
	836	}
	837	else if ( argc > 1 && QString(argv[1]) == "-n" ) {
	838	QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::NormalColor );
	839	argc--;
	840	argv++;
	841	}
	842	else {
	843	QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::CustomColor );
	844	}
	845
	846	<a href="qapplication.html">QApplication</a> a( argc, argv );
	847
	848	ImageIconProvider iip;
	849	<a name="x1362"></a> QFileDialog::<a href="qfiledialog.html#setIconProvider">setIconProvider</a>( &iip );
	850
	851	if ( argc <= 1 ) {
	852	// Create a window which looks after its own existence.
	853	ImageViewer *w =
	854	new ImageViewer(0, "new window", Qt::WDestructiveClose \| Qt::WResizeNoErase );
	855	<a name="x1364"></a> w-><a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Image Viewer");
	856	w-><a href="qwidget.html#show">show</a>();
	857	} else {
	858	for ( int i=1; i<argc; i++ ) {
	859	// Create a window which looks after its own existence.
	860	ImageViewer *w =
	861	new ImageViewer(0, argv[i], Qt::WDestructiveClose \| Qt::WResizeNoErase );
	862	w-><a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Image Viewer");
	863	w->loadImage( argv[i] );
	864	w-><a href="qwidget.html#show">show</a>();
	865	}
	866	}
	867
	868	QObject::<a href="qobject.html#connect">connect</a>(qApp, SIGNAL(<a href="qapplication.html#lastWindowClosed">lastWindowClosed</a>()), qApp, SLOT(<a href="qapplication.html#quit">quit</a>()));
	869
	870	return a.<a href="qapplication.html#exec">exec</a>();
	871	}
	872	</pre>
	873
	874	<p>See also <a href="examples.html">Examples</a>.
	875
	876	<!-- eof -->
	877	<p><address><hr><div align=center>
	878	<table width=100% cellspacing=0 border=0><tr>
	879	<td>Copyright © 2007
	880	<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
	881	<td align=right><div align=right>Qt 3.3.8</div>
	882	</table></div></address></body>
	883	</html>

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