Event Handler with both Mouse and Paint event arguments

Question

Is it possible to construct an event handler which has both mouse and paint
event arguments. Are there examples out there which utilize this type of event
handler ? If so can someone please direct me to it. Thank you. Something like this ?! Is this legal ?

private void Painter_MouseDown(object sender, MouseEventArgs e, PaintEventArgs p)

Henry Lagos · Answer

The problem is the following: You have two objects a photo and a drawing both of which implement the interface IPhotoDraw which "decorates" the objects with a string tag and/or a colored border when an event is fired. I decided that the event would be a mouse click which would place the tag or the border on each of the objects. The problem was that I couldn't figure out a way in which to fire a paint event upon a mouse click. Refreshing the screen after implementing the decorators is an option. I tried creating an EventHandler Method + EventArgs Class for this problem but was sort of confused on where to place it and where to fire it from. If you have any suggestions they are welcome . Thank You.

Henry Lagos · Answer

Firstly, thank you for your replies. I fooled around with both suggestions and decided to apply the Invalidate( ) method since it requires less typing and is more direct. The program below utilizes the Invalidate( ) method and runs. However, I like the idea of creating the custom-generated event handler and would like to be able to execute programs in that manner as well. How would you apply the an EventHandler + EventArgs class for this problem ? Perhaps ... public class MousePaintEventArgs : EventArgs { public MousePaintEventArgs ( Object source,MouseEventArgs e, PaintEventArgs p ) { public MouseEventArgs me; public PaintEventArgs pe; this.me = e; this.pe = p; } ???????????????????????????? suggestions are welcome ???????????? using System; using System.Drawing; using System.Drawing.Drawing2D; using System.Windows.Forms; using System.Collections.Generic; using System.Text; using Given; // Decorator Pattern Example Judith Bishop Aug 2007 // Draws a photograph and a user-generated drawing in a window // of fixed size . Has decorators that are BorderedPhotos and // TaggedPhotos that can be composed and added in different // combinations namespace Given { interface IPhotoDraw { void Drawer( Object source, PaintEventArgs e ); void Drawer2( Object source, PaintEventArgs e ); } // The original Photo class public class Photo : Form, IPhotoDraw { Image image; public Photo ( ) { image = new Bitmap( "jug.jpg" ); this.Text = "Lemonade"; this.Paint += new PaintEventHandler( Drawer ); } public void Drawer( Object source, PaintEventArgs e ) { e.Graphics.DrawImage( image, 30, 20 ); } public void Drawer2( Object source, PaintEventArgs e ) { } } // Hominid class in which a user-drawing can be decorated // with tags and borders public class Hominid : Form, IPhotoDraw { static Image image; private Pen p; public string pen_color = "red"; private bool mouse_down = false; private Point last_point = Point.Empty; private Graphics graphics, gfx_seen; public Hominid ( ) { image = new Bitmap( "human.jpg" ); graphics = Graphics.FromImage(image); p = new Pen(Color.FromName(pen_color)); this.BackColor = Color.Blue; this.Text = "Hominid"; this.Paint += new PaintEventHandler( Drawer ); this.MouseDown += new MouseEventHandler(this.User_Drawing_MouseDown ); this.MouseUp += new MouseEventHandler(this.User_Drawing_MouseUp ); this.MouseMove += new MouseEventHandler(this.User_Drawing_MouseMove ); } private void User_Drawing_MouseDown(object sender, MouseEventArgs e ) { if ( e.Button == MouseButtons.Right ) { image.Save("human.bmp",System.Drawing.Imaging.ImageFormat.Bmp); } else { mouse_down = true; } } private void User_Drawing_MouseUp(object sender, MouseEventArgs e ) { last_point = new Point(e.X, e.Y); mouse_down = false; } protected void User_Drawing_MouseMove(object sender, MouseEventArgs e ) { if ( mouse_down ) { Point pMousePos = new Point(e.X, e.Y); gfx_seen = CreateGraphics(); gfx_seen.DrawLine(new Pen(Color.Black),pMousePos, last_point); graphics.DrawLine(new Pen(Color.Black),pMousePos, last_point); } last_point = new Point(e.X, e.Y); } public void Drawer( Object source, PaintEventArgs e ) { e.Graphics.DrawImage( image, 30, 20 ); } public void Drawer2( Object source, PaintEventArgs e ) { } } } class DecoratorPatternExample { // This simple BorderedPhoto decorator adds a colored border of fixed size class BorderedPhoto : Form, IPhotoDraw { IPhotoDraw photo; Color color; public BorderedPhoto( IPhotoDraw p, Color c ) { photo = p; color = c; this.Paint += new PaintEventHandler( Drawer ); this.MouseDown += new MouseEventHandler( Border_Check ); } public void Drawer( Object source, PaintEventArgs e ) { photo.Drawer( source, e ); } public void Drawer2( Object source, PaintEventArgs e ) { photo.Drawer2( source, e ); e.Graphics.DrawRectangle( new Pen( color, 10 ), 25, 15, 215, 225 ); } public void Border_Check( Object source, MouseEventArgs e ) { if ( e.Button == MouseButtons.Left ) { this.Paint += new PaintEventHandler( Drawer2 ); Invalidate( ); } else { this.Paint -= new PaintEventHandler( Drawer2 ); Invalidate( ); } } } // The TaggedPhoto decorator keeps track of the tag number which it // a specific place to be written class TaggedPhoto : Form, IPhotoDraw { IPhotoDraw photo; string tag; int number; static int count; static List tags = new List ( ); public TaggedPhoto( IPhotoDraw p, string t ) { photo = p; tag = t; tags.Add(tag); number = ++count; this.Paint += new PaintEventHandler( Drawer ); this.MouseDown += new MouseEventHandler( Tag_Check ); } public void Drawer( Object source, PaintEventArgs e ) { photo.Drawer( source, e ); } public void Drawer2( Object source, PaintEventArgs e ) { photo.Drawer2( source, e ); e.Graphics.DrawString( tag, new Font( "Arial", 16 ), new SolidBrush( Color.Black ), new PointF( 80, 80+number*20 ) ); } public string ListTaggedPhotos( ) { string s = "Tagged Photos are: "; foreach( string tag in tags ) s+= tag+" "; return s; } public void Tag_Check( Object source, MouseEventArgs e ) { if ( e.Button == MouseButtons.Right ) { this.Paint += new PaintEventHandler( Drawer2 ); Invalidate( ); } else { this.Paint -= new PaintEventHandler( Drawer2 ); Invalidate( ); } } } // Application.Run acts as a simple client static void Main( ) { IPhotoDraw photo, drawing; TaggedPhoto colorTaggedPhoto, foodTaggedPhoto, composition2; BorderedPhoto composition1; // Compose a photo with two TaggedPhotos and a Green BorderedPhoto photo = new Photo( ); Application.Run( (Photo)photo ); foodTaggedPhoto = new TaggedPhoto( photo, "Lemonade" ); //Application.Run( foodTaggedPhoto ); colorTaggedPhoto = new TaggedPhoto( foodTaggedPhoto, "Green" ); Application.Run( colorTaggedPhoto ); composition1 = new BorderedPhoto( colorTaggedPhoto, Color.Green ); Application.Run( composition1 ); Console.WriteLine( colorTaggedPhoto.ListTaggedPhotos( ) ); // Compose a drawing with two TaggedPhotos and a Green Bordered Drawing drawing = new Hominid( ); Application.Run( (Hominid)drawing ); foodTaggedPhoto = new TaggedPhoto( drawing, "Hominid" ); Application.Run( foodTaggedPhoto ); colorTaggedPhoto = new TaggedPhoto( foodTaggedPhoto, "Orange" ); Application.Run( colorTaggedPhoto ); composition1 = new BorderedPhoto( colorTaggedPhoto, Color.Orange ); Application.Run( composition1 ); Console.WriteLine( colorTaggedPhoto.ListTaggedPhotos( ) ); // Compose a drawing with one TaggedPhoto and a Red Bordered Drawing drawing = new Hominid( ); Application.Run( (Hominid)drawing ); composition1 = new BorderedPhoto( drawing, Color.Red ); Application.Run( composition1 ); composition2 = new TaggedPhoto( composition1, "Stick Figure" ); Application.Run( composition2 ); Console.WriteLine( composition2.ListTaggedPhotos( ) ); } }

Ryan Alford · Answer

If you call the Invalidate() method inside of your Mouse Event, it will cause the Paint event to fire.....therefore firing both events.

Bechir Bejaoui · Answer

Not like this, you shoud derive an object from eventArgs and customize it so it supports a mouse tasks but tell me exactly what you want to do may be I give you a better idea

Event Handler with both Mouse and Paint event arguments

Answers (4)