Full instance of Image Viewer in Java implementation _java

Source: Internet
Author: User

This article describes the Java implementation of the image viewer. Share to everyone for your reference. Specifically as follows:

1. Mycanvas.java:

Package pictureviewer;
Import java.awt.*;
Import java.awt.event.*;
Import java.awt.image.*;
  public class MyCanvas extends Canvas implements componentlistener{private BufferedImage bi;
  Private Image im;
  private int image_width;
  private int image_height;
    public void SetImage (BufferedImage bi) {this.bi = bi;
  This.zoom (); public void Paint (Graphics g) {G.drawimage (IM, (This.getwidth ()-image_width)/2, (This.getheight ()-image_height)/2,t
  His);
      public void componentresized (ComponentEvent e) {if (bi!= null) {System.out.println ("resize!!");
      This.zoom ();
    This.repaint (); Componentmoved (ComponentEvent e) {} public void Componentshown (ComponentEvent e) {} is public void comp
    Onenthidden (ComponentEvent e) {} public void Zoom () {if (bi = null) return;
    int screen_width = This.getwidth ();
    int screen_height = This.getheight ();
    Double screen_proportion = 1.0 * SCREEN_HEIGHT/SCREEN_WIDTH; System.out.pRintln ("Screen:w" +screen_width+ ", H" +screen_height+ ", P0" +screen_proportion);
    Image_width = Bi.getwidth (this);
    Image_height = Bi.getheight (this);
    Double image_proportion = 1.0 * IMAGE_HEIGHT/IMAGE_WIDTH;
    System.out.println ("Image:w" +image_width+ ", H" +image_height+ ", p1" +image_proportion);
      if (Image_proportion > screen_proportion) {image_height = Screen_height;  
      image_width = (int) (image_height/image_proportion);
    System.out.println ("P1>p0 w=" +image_width);
      }else{image_width = screen_width;  
      Image_height = (int) (image_width * image_proportion);
    System.out.println ("P0>p1 h=" +image_height);
  im = Bi.getscaledinstance (image_width,image_height,image.scale_smooth);

 }
}

2. Myfilter.java:

Package pictureviewer;
Import Java.io.File;
Import Java.io.FilenameFilter;
public class Myfilter implements filenamefilter{
  private string[] extension;  
  Public Myfilter () {
    extension = new string[]{". jpg", ". JPG ",". gif ",". GIF ",". png ",". PNG ",". jpeg ",". JPEG "}; 
  }
  Public Myfilter (string[] extension) {
    this.extension = extension; 
  }
  Public Boolean accept (File dir,string name) {for
    (String s:extension) {
      if (Name.endswith (s)) {
        return true;
      }  
    return false; 
  }  
}

3. Pictureviewer.java:

Package pictureviewer;
Import java.awt.*;
Import java.awt.event.*;
Import java.awt.image.*;
Import java.io.*;
Import javax.imageio.*;
  public class PictureViewer implements actionlistener{private frame frame;
  Private MyCanvas MC;
  Private String Fpath;
  Private String fname;
  Private file[] files;
  private int findex; 
  Private FileDialog fd_load;
  private Myfilter filter;
  Private Button Previous;
  Private Button Next;
  public static void Main (String args[]) throws Exception {new PictureViewer (). Init ();
    The public void init () {frame = new frame ("PictureViewer");
    panel PB = new Panel ();
    Button select = New Button ("Select Picture");
    Previous = New button ("Last Sheet");
    Next = New button ("Next sheet");
    Select.addactionlistener (this);
    Previous.addactionlistener (this);
    Next.addactionlistener (this);
    Pb.add (select);
    Pb.add (previous); 
    Pb.add (next);
    MC = new MyCanvas ();
    Mc.setbackground (New Color (200,210,230)); Mc.addcomponentlistener(MC);
    Frame.add (Pb, "North");
    Frame.add (MC, "Center");
    Frame.setsize (360,360);
    Frame.setlocation (400,200); 
      Frame.addwindowlistener (New Windowadapter () {public void windowclosing (WindowEvent e) {system.exit (0); 
    }  
    }); 
    Frame.setvisible (TRUE);
    This.validatebutton ();
    Filter = new Myfilter ();
    Fd_load = new FileDialog (frame, "Open file", filedialog.load);
  Fd_load.setfilenamefilter (filter);
    The public void actionperformed (ActionEvent e) {String command = E.getactioncommand ();
      if (Command.equals ("select Picture")) {fd_load.setvisible (true);
      Fpath = Fd_load.getdirectory ();
      fname = Fd_load.getfile (); 
        if ((Fpath!= null) && (fname!= null)) {This.display (new File (Fpath + fname));
        Files = new File (Fpath). Listfiles (filter);
      This.setindex ();
      }}else if (Command.equals ("previous")) {findex--;
      if (findex<0) Findex = 0;
    This.display (Files[findex]); }elseif (command.equals ("next Sheet")) {findex++;
      if (Findex >= files.length) Findex = files.length-1;
    This.display (Files[findex]);
  } This.validatebutton ();
      public void display (File f) {try{BufferedImage bi = imageio.read (f);
      Mc.setimage (BI);
    Frame.settitle ("PictureViewer-[" + f.getname () + "]");
    }catch (Exception e) {e.printstacktrace ();
  } mc.repaint (); 
    public void Setindex () {File current = new file (Fpath + fname); 
        if (Files!= null) {for (int i=0;i<files.length;i++) {if (Current.equals (files[i))) {Findex = i; }}} public void Validatebutton () {previous.setenabled (files!=null) && (Findex >
    0)); 
  Next.setenabled ((files!=null) && (findex< (files.length-1)); }
}

I hope this article will help you with your Java programming.

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