Swing Hacks

Display Dates in a Custom Calendar #4

Chapter 1, Basic JComponents

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HACK

This loads the images in the constructor and sets up date formatters for the

month, year, and day. Override the

paintComponent( ) method to turn on

anti-aliasing, draw the background, and then draw the month and year for

the current date.

You’ll notice that there is a default date in case the devel-

oper doesn’t set one (always a good practice).

Draw the Days of the Month

The java.util.Calendar object handles all date calculations, so let’s start

there. You’ll need two calendars: one to represent the current date (

today)

and one that you update as you loop through the grid of dates (

cal). Here’s

what that looks like in code:

Calendar today = Calendar.getInstance( );

today.setTime(date);

Calendar cal = Calendar.getInstance( );

cal.setTime(date);

protected SimpleDateFormat year = new SimpleDateFormat("yyyy");

protected SimpleDateFormat day = new SimpleDateFormat("d");

protected Date date = new Date( );

public void setDate(Date date) {

this.date = date;

}

public CalendarHack( ) {

background = new ImageIcon("calendar.png").getImage( );

highlight = new ImageIcon("highlight.png").getImage( );

day_img = new ImageIcon("day.png").getImage( );

this.setPreferredSize(new Dimension(300,280));

}

public void paintComponent(Graphics g) {

((Graphics2D)g).setRenderingHint(RenderingHints.KEY_ANTIALIASING,

RenderingHints.VALUE_ANTIALIAS_ON); ...