File selector and Color picker

File Selector

The file selector JFileChooser is a common class for opening and saving files, and is commonly used to construct the following methods:

Construction Method Name Method meaning

JFileChooser () Create a file selector for the user's default directory

The JFileChooser (file currentdirectory) uses the specified file as the path to construct a filename selector

JFileChooser (String currentdirectorypath) creates a file selector using the specified path

Common methods of the file selector JFileChooser class

public void Showsavedialog (Component parent): Pop-up Save File Selector dialog box

public void Showopendialog (Component parent): Popup Open File Selector dialog box

Public file Getselecedfile (): Gets the selected file

Public file[] Getselectedfiles (): Get a list of multiple selected files, you need to set the file selector to multiple selection

Public File getcurrentdirectory (): Gets the current directory

public void SetCurrentDirectory (): Sets the current directory

public void Setdialogtitle (string dialogtitle): Sets the string displayed in the title bar of the file selector window

public void setmultiselectionenabled (Boolean B): Set to select multiple files

Attention:

Filechooser.addchoosablefilefilter (New Filenameextensionfilter ("JPEG picture file", "JPG", "jpeg"));

Filechooser.addchoosablefilefilter (New Filenameextensionfilter ("gif picture file", "GIF", "GIF"));

Filenameextensionfilter is a file filter, only jpeg,gif styles are displayed in this sample

Color Picker

The color picker, which is the Javax.swing.JcolorChooser class, can be used as a separate dialog box or as a component in any container, making it easy to develop an interface that contains a color selector

The JColorChooser is constructed as follows:

Public JColorChooser (): Create a color selector with an initial color of white

Public JColorChooser (Color Initialcolor): Creates a color selector with the specified initial color

Common methods of JColorChooser class

Public Color GetColor (): Gets the current color value of the color picker

public void SetColor (int c): Specifies the color Picker's current color

public void SetColor (int r,nt g,int b): Specifies the color picker's current color (RGB)

code example:

Package Ch10;import Java.awt.borderlayout;import Java.awt.color;import java.awt.event.*;import javax.swing.*;import Javax.swing.filechooser.filenameextensionfilter;public class Colorchoosertest extends JFrame implements     actionlistener{JPanel JP = new JPanel ();     JButton color = new JButton ("Click the color of My Settings label");     JButton open = new JButton ("Click I can open File");     Private jbutton[] Jbuttonarray = new Jbutton[]{color,open};     JLabel JL = new JLabel ("Click on the two buttons above, set the text color here or open the file");     JFileChooser filechooser = new JFileChooser ("g:\\");     Public Colorchoosertest () {for (int i=0;i<jbuttonarray.length;i++) {jp.add (jbuttonarray[i]);     Jbuttonarray[i].addactionlistener (this);     } this.add (Jl,borderlayout.south);     This.add (JP);     Filechooser.removechoosablefilefilter (Filechooser.getchoosablefilefilters () [0]);//Initialize the file selector and delete the original file selector     Filechooser.addchoosablefilefilter (New Filenameextensionfilter ("JPEG picture file", "JPG", "jpeg")); Filechooser.addchoosablefilefilter (New Filenameextensionfilter ("gif picture file", "GIF", "GIF"));     Filenameextensionfilter file filter, this sample can only display jpg,gif style this.settitle ("File and color selection");     This.setbounds (200,200,400,300);     This.setvisible (TRUE);     This.setdefaultcloseoperation (Jframe.exit_on_close); } public void actionperformed (ActionEvent a) {if (A.getsource () ==jbuttonarray[0]) {Color r = Jcolorch     Ooser.showdialog (This, "Choose desired Color", Color.cyan),//Popup Color selection Dialog jl.settext ("The color of the text becomes the color of your choice");     Jl.setforeground (R); } else if (A.getsource () ==jbuttonarray[1]) {filechooser.showopendialog (this);//Popup Open File Dialog Jl.settext ("You choose to play     Open a file selector ");     }} public static void Main (String args[]) {new colorchoosertest (); }}

File selector and Color picker