投稿
  1. 首页
  2. 软件运维

C++应用程序中，画图程序 创建画笔的代码 急~~

英语手抄报图片 • 2023-4-12 • 软件运维 • 阅读 5

C++应用程序中，画图程序 创建画笔的代码 急~~,第1张

要想在MFC中画出有颜色的线条，首先就要设置DC的画笔，我们可以按如下方法来设置画笔：

第一步：在View类中添加一个COLORREF类型的数据成员m_Color（用来保存画笔颜色值），在构造函数中对其初始化，

m_Color(RGB(255,0,0))

第二步：在WM_LBUTTONDOWN和WM_LBUTTONUP消息的处理函数OnLButtonDown和OnLButtonUp中添加如下代码：

void CdrView::OnLButtonDown(UINT nFlags, CPoint point)

{

// TODO: Add your message handler code here and/or call default

m_StartPoint=point//用来保存画线起始点的位置，即鼠标左键第一次按下时的位置，类型为CPoint

CView::OnLButtonDown(nFlags, point)

}

void CdrView::OnLButtonUp(UINT nFlags, CPoint point)

{

// TODO: Add your message handler code here and/or call default

//第一种方法，用HDC绘图，使用API函数设置画笔颜色

/*HDC hdc

hdc=::GetDC(m_hWnd)

::SelectObject(hdc,CreatePen(PS_SOLID,1,m_Color))//向设备上下文（设备描述表）中插入由CreatePen函数创建的画笔

::MoveToEx(hdc,m_StartPoint.x,m_StartPoint.y,NULL)

::LineTo(hdc,point.x,point.y)

::ReleaseDC(m_hWnd,hdc)*/

//第二种，用CDC类绘图，使用CPen类构造画笔

/*CDC aDC

CPen pen(PS_SOLID,1,m_Color)//建立一个画笔类对象，构造时设置画笔属性

aDC.m_hDC=::GetDC(m_hWnd)

aDC.SelectObject(&pen)

aDC.MoveTo(m_StartPoint)

aDC.LineTo(point)

::ReleaseDC(m_hWnd,aDC.m_hDC)*/

//第三种，用CClient类绘图，使用CPen类构造画笔，跟第二种方法不同的是用CClientDC时不用手动去获取DC，和释放DC

CClientDC aDC(this)//CClientDC的构造函数需要一个参数，这个参数是指向绘图窗口的指针，我们用this指针就可以了

CPen pen(PS_SOLID,1,m_Color)////建立一个画笔类对象，构造时设置画笔属性

aDC.SelectObject(&pen)

aDC.MoveTo(m_StartPoint)

aDC.LineTo(point)

CView::OnLButtonUp(nFlags, point)

}

void CdrView::OnMouseMove(UINT nFlags, CPoint point)

{

// TODO: Add your message handler code here and/or call default

CView::OnMouseMove(nFlags, point)

}

运行程序，就可以画出红色的线条来，如果想画其它颜色，只需要设置m_Color的值即可，例如，要设置成绿色，可以在View类的构造函数处把m_Color(RGB(255,0,0))改写成m_Color(RGB(0,255,0))。颜色的改变是通过设置RGB(0,255,0)中的三个参数来实现的。RGB中的三个参数分别对应三原色的红、绿、蓝，每一个参数的取值范围都是0～255，通过不同数值的组合，就可以画出各种各样的颜色来了。

新建一个java文件,取名叫做PaintJava.java

代码如下:

import java.applet.*

import java.awt.*

import java.awt.event.*

import java.util.*

import javax.swing.*

import java.awt.geom.*

import java.io.*

class Point implements Serializable

{

int x,y

Color col

int tool

int boarder

Point(int x, int y, Color col, int tool, int boarder)

{

this.x = x

this.y = y

this.col = col

this.tool = tool

this.boarder = boarder

}

}

class paintboard extends Frame implements ActionListener,MouseMotionListener,MouseListener,ItemListener

{

int x = -1, y = -1

int con = 1//画笔大小

int Econ = 5//橡皮大小

int toolFlag = 0//toolFlag:工具标记

//toolFlag工具对应表：

//（0--画笔）；（1--橡皮）；（2--清除）；

//（3--直线）；（4--圆）；（5--矩形）；

Color c = new Color(0,0,0)//画笔颜色

BasicStroke size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)//画笔粗细

Point cutflag = new Point(-1, -1, c, 6, con)//截断标志

Vector paintInfo = null//点信息向量组

int n = 1

FileInputStream picIn = null

FileOutputStream picOut = null

ObjectInputStream VIn = null

ObjectOutputStream VOut = null

// *工具面板--画笔，直线，圆，矩形，多边形,橡皮，清除*/

Panel toolPanel

Button eraser, drLine,drCircle,drRect

Button clear ,pen

Choice ColChoice,SizeChoice,EraserChoice

Button colchooser

Label 颜色,大小B,大小E

//保存功能

Button openPic,savePic

FileDialog openPicture,savePicture

paintboard(String s)

{

super(s)

addMouseMotionListener(this)

addMouseListener(this)

paintInfo = new Vector()

/*各工具按钮及选择项*/

//颜色选择

ColChoice = new Choice()

ColChoice.add("black")

ColChoice.add("red")

ColChoice.add("blue")

ColChoice.add("green")

ColChoice.addItemListener(this)

//画笔大小选择

SizeChoice = new Choice()

SizeChoice.add("1")

SizeChoice.add("3")

SizeChoice.add("5")

SizeChoice.add("7")

SizeChoice.add("9")

SizeChoice.addItemListener(this)

//橡皮大小选择

EraserChoice = new Choice()

EraserChoice.add("5")

EraserChoice.add("9")

EraserChoice.add("13")

EraserChoice.add("17")

EraserChoice.addItemListener(this)

////////////////////////////////////////////////////

toolPanel = new Panel()

clear = new Button("清除")

eraser = new Button("橡皮")

pen = new Button("画笔")

drLine = new Button("画直线")

drCircle = new Button("画圆形")

drRect = new Button("画矩形")

openPic = new Button("打开图画")

savePic = new Button("保存图画")

colchooser = new Button("显示调色板")

//各组件事件监听

clear.addActionListener(this)

eraser.addActionListener(this)

pen.addActionListener(this)

drLine.addActionListener(this)

drCircle.addActionListener(this)

drRect.addActionListener(this)

openPic.addActionListener(this)

savePic.addActionListener(this)

colchooser.addActionListener(this)

颜色 = new Label("画笔颜色",Label.CENTER)

大小B = new Label("画笔大小",Label.CENTER)

大小E = new Label("橡皮大小",Label.CENTER)

//面板添加组件

toolPanel.add(openPic)

toolPanel.add(savePic)

toolPanel.add(pen)

toolPanel.add(drLine)

toolPanel.add(drCircle)

toolPanel.add(drRect)

toolPanel.add(颜色)toolPanel.add(ColChoice)

toolPanel.add(大小B)toolPanel.add(SizeChoice)

toolPanel.add(colchooser)

toolPanel.add(eraser)

toolPanel.add(大小E)toolPanel.add(EraserChoice)

toolPanel.add(clear)

//工具面板到APPLET面板

add(toolPanel,BorderLayout.NORTH)

setBounds(60,60,900,600)setVisible(true)

validate()

//dialog for save and load

openPicture = new FileDialog(this,"打开图画",FileDialog.LOAD)

openPicture.setVisible(false)

savePicture = new FileDialog(this,"保存图画",FileDialog.SAVE)

savePicture.setVisible(false)

openPicture.addWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ openPicture.setVisible(false)}

})

savePicture.addWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ savePicture.setVisible(false)}

})

addWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ System.exit(0)}

})

}

public void paint(Graphics g)

{

Graphics2D g2d = (Graphics2D)g

Point p1,p2

n = paintInfo.size()

if(toolFlag==2)

g.clearRect(0,0,getSize().width,getSize().height)//清除

for(int i=0i<n i++){

p1 = (Point)paintInfo.elementAt(i)

p2 = (Point)paintInfo.elementAt(i+1)

size = new BasicStroke(p1.boarder,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

g2d.setColor(p1.col)

g2d.setStroke(size)

if(p1.tool==p2.tool)

{

switch(p1.tool)

{

case 0://画笔

Line2D line1 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y)

g2d.draw(line1)

break

case 1://橡皮

g.clearRect(p1.x, p1.y, p1.boarder, p1.boarder)

break

case 3://画直线

Line2D line2 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y)

g2d.draw(line2)

break

case 4://画圆

Ellipse2D ellipse = new Ellipse2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y))

g2d.draw(ellipse)

break

case 5://画矩形

Rectangle2D rect = new Rectangle2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y))

g2d.draw(rect)

break

case 6://截断，跳过

i=i+1

break

default :

}//end switch

}//end if

}//end for

}

public void itemStateChanged(ItemEvent e)

{

if(e.getSource()==ColChoice)//预选颜色

{

String name = ColChoice.getSelectedItem()

if(name=="black")

{c = new Color(0,0,0)}

else if(name=="red")

{c = new Color(255,0,0)}

else if(name=="green")

{c = new Color(0,255,0)}

else if(name=="blue")

{c = new Color(0,0,255)}

}

else if(e.getSource()==SizeChoice)//画笔大小

{

String selected = SizeChoice.getSelectedItem()

if(selected=="1")

{

con = 1

size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

}

else if(selected=="3")

{

con = 3

size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

}

else if(selected=="5")

{con = 5

size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

}

else if(selected=="7")

{con = 7

size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

}

else if(selected=="9")

{con = 9

size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL)

}

}

else if(e.getSource()==EraserChoice)//橡皮大小

{

String Esize = EraserChoice.getSelectedItem()

if(Esize=="5")

{ Econ = 5*2}

else if(Esize=="9")

{ Econ = 9*2}

else if(Esize=="13")

{ Econ = 13*2}

else if(Esize=="17")

{ Econ = 17*3}

}

}

public void mouseDragged(MouseEvent e)

{

Point p1

switch(toolFlag){

case 0://画笔

x = (int)e.getX()

y = (int)e.getY()

p1 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p1)

repaint()

break

case 1://橡皮

x = (int)e.getX()

y = (int)e.getY()

p1 = new Point(x, y, null, toolFlag, Econ)

paintInfo.addElement(p1)

repaint()

break

default :

}

}

public void mouseMoved(MouseEvent e) {}

public void update(Graphics g)

{

paint(g)

}

public void mousePressed(MouseEvent e)

{

Point p2

switch(toolFlag){

case 3://直线

x = (int)e.getX()

y = (int)e.getY()

p2 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p2)

break

case 4: //圆

x = (int)e.getX()

y = (int)e.getY()

p2 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p2)

break

case 5: //矩形

x = (int)e.getX()

y = (int)e.getY()

p2 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p2)

break

default :

}

}

public void mouseReleased(MouseEvent e)

{

Point p3

switch(toolFlag){

case 0://画笔

paintInfo.addElement(cutflag)

break

case 1: //eraser

paintInfo.addElement(cutflag)

break

case 3://直线

x = (int)e.getX()

y = (int)e.getY()

p3 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p3)

paintInfo.addElement(cutflag)

repaint()

break

case 4: //圆

x = (int)e.getX()

y = (int)e.getY()

p3 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p3)

paintInfo.addElement(cutflag)

repaint()

break

case 5: //矩形

x = (int)e.getX()

y = (int)e.getY()

p3 = new Point(x, y, c, toolFlag, con)

paintInfo.addElement(p3)

paintInfo.addElement(cutflag)

repaint()

break

default:

}

}

public void mouseEntered(MouseEvent e){}

public void mouseExited(MouseEvent e){}

public void mouseClicked(MouseEvent e){}

public void actionPerformed(ActionEvent e)

{

if(e.getSource()==pen)//画笔

{toolFlag = 0}

if(e.getSource()==eraser)//橡皮

{toolFlag = 1}

if(e.getSource()==clear)//清除

{

toolFlag = 2

paintInfo.removeAllElements()

repaint()

}

if(e.getSource()==drLine)//画线

{toolFlag = 3}

if(e.getSource()==drCircle)//画圆

{toolFlag = 4}

if(e.getSource()==drRect)//画矩形

{toolFlag = 5}

if(e.getSource()==colchooser)//调色板

{

Color newColor = JColorChooser.showDialog(this,"调色板",c)

c = newColor

}

if(e.getSource()==openPic)//打开图画

{

openPicture.setVisible(true)

if(openPicture.getFile()!=null)

{

int tempflag

tempflag = toolFlag

toolFlag = 2

repaint()

try{

paintInfo.removeAllElements()

File filein = new File(openPicture.getDirectory(),openPicture.getFile())

picIn = new FileInputStream(filein)

VIn = new ObjectInputStream(picIn)

paintInfo = (Vector)VIn.readObject()

VIn.close()

repaint()

toolFlag = tempflag

}

catch(ClassNotFoundException IOe2)

{

repaint()

toolFlag = tempflag

System.out.println("can not read object")

}

catch(IOException IOe)

{

repaint()

toolFlag = tempflag

System.out.println("can not read file")

}

}

}

if(e.getSource()==savePic)//保存图画

{

savePicture.setVisible(true)

try{

File fileout = new File(savePicture.getDirectory(),savePicture.getFile())

picOut = new FileOutputStream(fileout)

VOut = new ObjectOutputStream(picOut)

VOut.writeObject(paintInfo)

VOut.close()

}

catch(IOException IOe)

{

System.out.println("can not write object")

}

}

}

}//end paintboard

public class PaintJava

{

public static void main(String args[])

{ new paintboard("画图程序")}

}

累啊..给分吧...!!

欢迎分享，转载请注明来源：内存溢出

原文地址: http://outofmemory.cn/yw/8000973.html

赞 (0)
打赏 微信扫一扫 微信扫一扫 支付宝扫一扫 支付宝扫一扫
英语手抄报图片 英语手抄报图片 一级用户组
0 0
上一篇 2023-04-12
下一篇 2023-04-12

发表评论

登录后才能评论

评论列表（0条）

保存