Qt之对话框设计——利用QPalette改变控件颜色

QPalette类相当于对话框或控件的调色板，它管理着控件或窗体的所有颜色信息，每个窗体或控件都包含一个QPalette对象，在显示时按照它的QPalette对象中对各部分各状态下的颜色的描述来进行绘制。

QPalette类有两个基本的概念，一个是ColorGroup，另一个是ColorRole。

void QPalette::setColor ( ColorRole role, const QColor & color );

void QPalette::setColor ( ColorGroup group, ColorRole role, const QColor & color );

void QPalette::setBrush ( ColorRole role, const QBrush & brush );

void QPalette::setBrush ( ColorGroup group, ColorRole role, const QBrush & brush );

ColorGroup：

QPalette::Disabled	不可用状态
QPalette::Active	活跃状态（获得焦点）
QPalette::Inactive	不活跃状态（未获得焦点）

ColorRole：

QPalette::Window	一个常规的背景颜色
QPalette::Background	这个值是废弃的，使用window代替
QPalette::WindowText	一个一般的前景颜色
QPalette::Foreground	这个值是废弃的，使用windowText代替.
QPalette::Base	最长使用来作为text背景颜色为整个widget，但是也能被用来为其他的绘画，像combobox的上下清单的背景和工具栏句柄。它通常是白的或者其他亮的颜色.
QPalette::AlternateBase	被用来作为轮流的背景颜色，轮流的行颜色
QPalette::ToolTipBase	被用来作为背景颜色为QToolTip和QWhatsThis。工具尖端使用QPalette不活跃的颜色组，因为工具尖端不是活跃的窗口.
QPalette::ToolTipText	被用来作为前景颜色为QToolTip和QWhatsThis.工具尖端使用QPalette不活跃的颜色组，因为工具尖端不是活跃的窗口.
QPalette::Text	前景颜色使用base.这通常和windowText相同，它一定提供好的对比window和base
QPalette::Button	button背景颜色。这个背景颜色能是不同于window作为一些风格，要求一个不同的背景颜色作为button
QPalette::ButtonText	一个前景颜色被用来作为button颜色.
QPalette::BrightText	一个text颜色是很不同于windowText，很好的对比与dark。典型的被用来为text，需要被画，在text或者windowText将给差的对比，就像在按下的button。注意text颜色能被用来为事情，而不只是单词；text颜色通常被用来为text，但是他是相当普通的使用text颜色角色为行，图标，等等。

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另外，在设置对话框和控件的背景色时还会用到：

void setAutoFillBackground ( bool enabled )；

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maindlg.h

#ifndef MAINDLG_H
#define MAINDLG_H

#include <QtGui/QDialog>
#include <QFrame>
#include <QComboBox>


class MainDlg : public QDialog
{
	Q_OBJECT

public:
	MainDlg(QWidget *parent = 0, Qt::WFlags flags = 0);
	~MainDlg();

	void createCtrlFrame();
	void createContentFrame();
	void fillColorList(QComboBox *);

public slots:
	void sl_window();
	void sl_windowText();
	void sl_button();
	void sl_buttonText();
	void sl_base();

private:
	QFrame *ctrlFrame;	//颜色选择面板
	QFrame *contentFrame;	//具体显示面板
	QComboBox *cbbWindow;
	QComboBox *cbbWindowText;
	QComboBox *cbbButton;
	QComboBox *cbbButtonText;
	QComboBox * cbbBase;
	
};

#endif // MAINDLG_H

maindlg.cpp

#include "maindlg.h"
#include <QPalette>
#include <QHBoxLayout>
#include <QVBoxLayout>
#include <QGridLayout>
#include <QStringList>
#include <QColor>
#include <QPixmap>
#include <QSpinBox>
#include <QTextEdit>
#include <QLineEdit>
#include <QPushButton>
#include <QLabel>

MainDlg::MainDlg(QWidget *parent, Qt::WFlags flags)
	: QDialog(parent, flags)
{
	createCtrlFrame();
	createContentFrame();

	QHBoxLayout *mainLayout = new QHBoxLayout(this);
	mainLayout->addWidget(ctrlFrame);
	mainLayout->addWidget(contentFrame);
	mainLayout->setMargin(10);
	mainLayout->setSpacing(5);
	mainLayout->setSizeConstraint(QLayout::SetFixedSize);
}

MainDlg::~MainDlg()
{

}

void MainDlg::fillColorList(QComboBox *cbb)
{
	QStringList colorNameList = QColor::colorNames();

	QString colorName;
	foreach(colorName,colorNameList)
	{
		QPixmap pix_color(70,20);
		pix_color.fill(QColor(colorName));

		cbb->addItem(QIcon(pix_color),NULL);
		cbb->setIconSize(QSize(70,20));
		cbb->setSizeAdjustPolicy(QComboBox::AdjustToContents);	//设置下拉列表的尺寸符合内容的大小
	}
}

void MainDlg::createCtrlFrame()
{
	ctrlFrame = new QFrame;

	QLabel *labWindow = new QLabel(tr("QPalette::Window:"));
	QLabel *labWindowText = new QLabel(tr("QPalette::WindowText:"));
	QLabel *labButton = new QLabel(tr("QPalette::Button:"));
	QLabel *labButtonText = new QLabel(tr("QPalette::ButtonText:"));
	QLabel *labBase = new QLabel(tr("QPalette::Base:"));

	cbbWindow = new QComboBox;
	fillColorList(cbbWindow);
	connect(cbbWindow,SIGNAL(activated(int)),this,SLOT(sl_window()));
	cbbWindowText = new QComboBox;
	fillColorList(cbbWindowText);
	connect(cbbWindowText,SIGNAL(activated(int)),this,SLOT(sl_windowText()));
	cbbButton = new QComboBox;
	fillColorList(cbbButton);
	connect(cbbButton,SIGNAL(activated(int)),this,SLOT(sl_button()));
	cbbButtonText = new QComboBox;
	fillColorList(cbbButtonText);
	connect(cbbButtonText,SIGNAL(activated(int)),this,SLOT(sl_buttonText()));
	cbbBase = new QComboBox;
	fillColorList(cbbBase);
	connect(cbbBase,SIGNAL(activated(int)),this,SLOT(sl_base()));
	
	int col_lab = 0;
	int col_cbb = 1;
	QGridLayout *ctrlLayout = new QGridLayout(ctrlFrame);
	ctrlLayout->addWidget(labWindow,0,col_lab);
	ctrlLayout->addWidget(labWindowText,1,col_lab);
	ctrlLayout->addWidget(labButton,2,col_lab);
	ctrlLayout->addWidget(labButtonText,3,col_lab);
	ctrlLayout->addWidget(labBase,4,col_lab);
	ctrlLayout->addWidget(cbbWindow,0,col_cbb);
	ctrlLayout->addWidget(cbbWindowText,1,col_cbb);
	ctrlLayout->addWidget(cbbButton,2,col_cbb);
	ctrlLayout->addWidget(cbbButtonText,3,col_cbb);
	ctrlLayout->addWidget(cbbBase,4,col_cbb);
	ctrlLayout->setMargin(5);
	ctrlLayout->setSpacing(5);
}

void MainDlg::createContentFrame()
{
	contentFrame = new QFrame;
	
	QLabel *labValue = new QLabel(tr("Please select one of the values:"));
	QSpinBox *spbValue = new QSpinBox;
	QHBoxLayout *valueLayout = new QHBoxLayout;
	valueLayout->addWidget(labValue);
	valueLayout->addWidget(spbValue);
	valueLayout->setSpacing(5);

	QLabel *labString = new QLabel(tr("Please input a string"));
	QLineEdit *edtString = new QLineEdit;
	QHBoxLayout *stringLayout = new QHBoxLayout;
	stringLayout->addWidget(labString);
	stringLayout->addWidget(edtString);
	stringLayout->setSpacing(5);

	QTextEdit *edtHelloQt = new QTextEdit(tr("Hello Qt!"));
	
	QPushButton *btnOk = new QPushButton(tr("OK"));
	QPushButton *btnCancel =new QPushButton(tr("Cancel"));
	QHBoxLayout *buttonLayout = new QHBoxLayout;
	buttonLayout->addStretch(1);
	buttonLayout->addWidget(btnOk);
	buttonLayout->addWidget(btnCancel);
	buttonLayout->setSpacing(5);

	QVBoxLayout *contentLayout = new QVBoxLayout(contentFrame);
	contentLayout->addLayout(valueLayout);
	contentLayout->addLayout(stringLayout);
	contentLayout->addWidget(edtHelloQt);
	contentLayout->addLayout(buttonLayout);
	contentLayout->setMargin(5);
	contentLayout->setSpacing(5);

	btnOk->setAutoFillBackground(true);
	btnCancel->setAutoFillBackground(true);
	contentFrame->setAutoFillBackground(true);
}

void MainDlg::sl_window()
{
	QStringList colorList = QColor::colorNames();
	QColor color = QColor(colorList[cbbWindow->currentIndex()]);
	QPalette p = contentFrame->palette();
	p.setColor(QPalette::Window,color);
	contentFrame->setPalette(p);
}

void MainDlg::sl_windowText()
{
	QStringList colorList = QColor::colorNames();
	QColor color = QColor(colorList[cbbWindowText->currentIndex()]);
	QPalette p = contentFrame->palette();
	p.setColor(QPalette::WindowText,color);
	contentFrame->setPalette(p);
}

void MainDlg::sl_button()
{
	QStringList colorNameList = QColor::colorNames();
	QColor m_color = QColor(colorNameList[cbbButton->currentIndex()]);
	QPalette p = contentFrame->palette();
	p.setColor(QPalette::Button,m_color);
	contentFrame->setPalette(p);
}

void MainDlg::sl_buttonText()
{
	QStringList colorNameList = QColor::colorNames();
	QColor m_color = QColor(colorNameList[cbbButtonText->currentIndex()]);
	QPalette p = contentFrame->palette();
	p.setColor(QPalette::ButtonText,m_color);
	contentFrame->setPalette(p);
}


void MainDlg::sl_base()
{
	QStringList colorNameList = QColor::colorNames();
	QColor m_color = QColor(colorNameList[cbbBase->currentIndex()]);
	QPalette p = contentFrame->palette();
	p.setColor(QPalette::Base,m_color);
	contentFrame->setPalette(p);
}

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