Multi-line area of Notepad (text area and scroll bar)

There are serious flaws in the input of single-line text, and it is not suitable for practical use, this section introduces a jtextare that can make multiple lines of input through a non-functional notepad.

JTextArea

JTextArea (): Create a text area with empty content

JTextArea (document DOC): Creates a text area with the specified document

JTextArea (document doc,string text,int rows,int columns): Create a text area with the specified document, number of rows, number of columns

JTextArea (int rows,int columns): Specifies the number of rows, the text area of the number of columns

JTextArea (String text): Specifies the text area of the text content

JTextArea (String text,int rows,int columns): Text area specifying text content and number of rows, columns

Some common methods of JTextArea:

public void append (String str): Appends the given text to the end of the document.

Boolean getlinewrap (): Gets the line wrapping policy for the text area.

public int getRows (): Returns the number of rows in the TextArea.

public boolean Getwrapstyleword (): Gets the line-wrapping method if the text area is to be wrapped.

public void Setwrapstyleword (Boolean word): Sets the line wrapping method (if the text area is to be wrapped)
public void Insert (String str, int pos): Inserts the specified text into the specified position.  
public void setcolumns (int columns): Sets the number of columns in this TextArea.

public void Setlinewrap (Boolean wrap): Sets the line wrapping policy for the text area.

public void setrows (int rows): Sets the number of rows for this TextArea.

public void Seteditable (Boolean B): Sets the editing state of the text area. A parameter of TRUE indicates an editable state, or false indicates a non-editable state

JScrollPane

JScrollPane (): Creates a scroll bar that can be displayed both horizontally and vertically

JScrollPane (Component view): Creates a scrollbar that displays the contents of the specified component, displaying horizontal and vertical scroll bars when the contents of the component exceed the view size
JScrollPane (Component view,int vsbpolicy,int hsbpolicy)  : Creates a scroll bar that displays the contents of the specified component with a scroll bar with the specified scroll policy
JScrollPane (int vsbpolicy,int hsbpolicy)  : Creates a scroll bar with the specified scroll policy
There are 6 main scrollbar strategies used in the construction method of the JScrollPane class:
     
    

      
     
 
      
 
       
Constant constant meaning
 
      
 
      
 
       
Horizontal_scrollbar_as_needed Show horizontal scroll bar when neededhorizontal_scrollbar_always always show horizontal scroll barhorizontal_scrollbar_never The horizontal scroll bar has not been displayed Vertical_scrollbar_as_needed Displays the vertical scrollbar Vertical_ when needed scrollbar_always                                                Always show vertical scroll bar   vertical_scrollbar_never No vertical scroll bar is displayed   
 
      
 
     
     
    
VERTICAL

public int gethorizontalscrollbarpolicy (): Gets the horizontal scrolling policy value

public int getverticalscrollbarpolicy (): Gets the vertical scrolling policy value

public void Gethorizontalscrollbarpolicy (): Set horizontal scrolling policy value

public void Getverticalscrollbarpolicy (): Set vertical scrolling policy value

public boolean iswheelscrollingenabled (): Sets whether to scroll in response to the mouse wheel

public void Setviewportview (conponent view): Sets the scroll component in the scroll bar

public void Setwheelscrollingenabled (Boolean Handlewheel): Start/Disable move response to mouse wheel scrolling

code example:

Package Ch10;import Java.awt.event.*;import javax.swing.*;p ublic class Notetextarea extends JFrame implements    actionlistener{private JPanel JP = new JPanel ();    JButton jb1 = new JButton ("Dot I wrap");    JButton jb2 = new JButton ("Dot I don't Break");    Private JTextArea JT = new JTextArea ();    Private JScrollPane js = new JScrollPane (JT);    Public Notetextarea () {jp.setlayout (null);    Jb1.setbounds (40,40,180,20);    Jb2.setbounds (280,40,180,20);    Jp.add (JB1);    Jp.add (JB2);    Jb1.addactionlistener (this);    Jb2.addactionlistener (this);    Js.setbounds (40,80,420,100);    Jp.add (JS);    Jt.setlinewrap (FALSE); for (int i=0;i<30;i++) {jt.append ("wrap line, no wrap!    ");    } this.add (JP);    This.setbounds (80,80,300,300);    This.setvisible (TRUE);    This.settitle ("Notepad multi-text area");    This.setdefaultcloseoperation (Jframe.exit_on_close);    public void actionperformed (ActionEvent a) {if (A.getsource () ==jb1) {Jt.setlinewrap (true);   } else if (A.getsource () ==jb2) {Jt.setlinewrap (false);    }} public static void Main (String args[]) {new Notetextarea (); }}

Multi-line area of Notepad (text area and scroll bar)