aclock.cpp

基于qte 2.3.7做的 趋势图控件

/****************************************************************************
** $Id: qt/examples/aclock/aclock.cpp   2.3.7   edited 2001-01-26 $
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of an example program for Qt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/

#include "aclock.h"
#include <qtimer.h>
#include <qpainter.h>
#include <qbitmap.h>
#include <stdio.h>
#include <stdlib.h>
#include <iostream.h>
#include <math.h>

/*
 监控volt值的变化，每0.5秒刷新一次
 使用方法：
 	Hwt_trend *m = new Hwt_trend( this, "Hwt_trend" );
    m->runDemo(1);  //自动演示，正弦变化
    
    定时设置 m->setVol(p); Hwt_trend自动监控volt值的变化，
    每0.5秒刷新一次，并显示柱状图及转换
	
	问题：
		绿色柱落后白线一格
*/

Hwt_trend::Hwt_trend( QWidget *parent, const char *name )
    : QWidget( parent, name )
{
    c = 0; flag=1; volt=0.0;
    demo =0;
    
    QTimer *internalTimer = new QTimer( this );	// create internal timer
    connect( internalTimer, SIGNAL(timeout()), SLOT(timeout()) );
    internalTimer->start( 500,false );	
    setMinimumSize( 396, 220 );
    setMaximumSize( 396, 220 );
    setBackgroundPixmap( QPixmap("trend0.png") );
    
    int i;
    pts = new QPointArray(60);
    for(i=0; i<30; i++){
    	point[i] = 0;
    	pts->putPoints( 2*i, 1, i*11+45,102 ); 
    	pts->putPoints( 2*i+1, 1, i*11+45,102 ); 
    }
    
    for(i=1; i<4; i++){
    	s[i].sprintf( "%d", i*10-30);
    }
    s[0] = s[3];
}


//
// The QTimer::timeout() signal is received by this slot.
//

void Hwt_trend::timeout()
{
    int t = c%30;
    
    if(demo)//test
    	volt = sin(c/2.2)*10; //c%7 - 3.0;
    //cout<<sin(t)<<endl;

    point[t] = volt;
    if(volt >10) 
    	point[t] = 10.0;
    else if (volt <-10) 
    	point[t] = -10.0;
    
    
    if(point[t] >= 1) {
    	pts->putPoints( 2*t+1, 1, t*11+45,50); 
    	pts->putPoints( (2*t+2)%60, 1, ((t+1)%30)*11+45,50); 
    }else{
    	pts->putPoints( 2*t+1, 1, t*11+45,102); 
    	pts->putPoints( (2*t+2)%60, 1, ((t+1)%30)*11+45,102); 
    }
    update();
    c++;
}


void Hwt_trend::paintEvent( QPaintEvent * )
{
    QPainter paint( this );
    //paint.setFont( QFont( "simsun", 14, QFont::Normal) );
    drawClock( &paint );
    
}

void Hwt_trend::drawClock( QPainter *paint )
{
    paint->save();
    paint->setPen( Qt::red );
    paint->drawPolyline( *pts );

    int i;
    paint->setPen( Qt::green );
    paint->setBrush( Qt::green );
    for(i=0; i<30; i++){
    	if(i==0)
    		paint->drawRect ( i*11+45, 113, 3, -point[i]*5 ) ;
    	else
    		paint->drawRect ( i*11+43, 113, 6, -point[i]*5 ) ;
    }
    paint->setPen( Qt::white );
    paint->drawLine( (c%30)*11+45, 43, (c%30)*11+45, 180);	
    
    paint->setPen( Qt::blue );
    s[c%30/10].sprintf( "%d", (c/10)*10);
    s[3] = s[0];
	for(i=0;i<4;i++){
    	paint->drawText( i*107+45-3*s[i].length(), 205, s[i] );	
    }
   paint->restore();
}

void Hwt_trend::setVol( float pvolt)
{
	if(pvolt > 10.0) 
		volt = 10.0;
	else if(pvolt < -10.0) 
		volt = -10.0;
	else
		volt = pvolt;
}

void Hwt_trend::runDemo( int t)
{
	if(t==0) demo = 0;
	else demo = 1;
}

//end