MacTech 1 to 12/MacTech-vol-1-12.toast/Source/MacTech® Magazine/Volume 12 - 1996/12.10 Oct 96/AdownsJavaObjects/Demo.java

Text File | 1996-09-11 | 4.6 KB | 197 lines | [TEXT/R*ch]

/*

Listing 1: Demo.java

Demo.java
Define and create a new instance of our applet.

*/

// Import the generic Java classes.
import java.applet.*;
import java.awt.*;
import java.io.*;
import java.lang.*;

//    Our applet class definition.
public    class Demo extends java.applet.Applet
{
    //    Instances of classes we need.
    ToolPalette            theToolPalette;
    public    Demo        myDemo;
    BackdropCanvas        theBackdropCanvas;
    NewButtonFrame        theNewButtonFrame;

//    Our first method.
    public void init()
    {
        //    Variables local to this method, used only to setup our applet.
        int            tempX = 320, tempY = 100;
        int            tempWidth = 300, tempHeight = 300;
        int            theColor;
        Color        menuColor[] = {     Color.black, Color.green,
                                                        Color.pink, Color.blue,
                                                        Color.lightGray, Color.red,
                                                        Color.cyan, Color.magenta,
                                                        Color.white, Color.darkGray,
                                                        Color.orange, Color.yellow,
                                                        Color.gray };

        //    Setup our applet display area.
        setBackground( Color.gray );
        setForeground( Color.black );
        setLayout( new BorderLayout() );

        //    We will want to refer to our applet later.
        myDemo = this;

        //    Create an instance of our drawing canvas.
        theBackdropCanvas = new BackdropCanvas();

        //    Now that our graphics canvas is ready, add it to the center of our applet.
        add( "Center", theBackdropCanvas );

        //    Our tool palette.
        theToolPalette = new ToolPalette( myDemo );

        //    A "dialog" to solicit input from the user.
        theNewButtonFrame = new NewButtonFrame( myDemo );

        //    Retrieve some default color information from our tool palette.
        theColor = theToolPalette.doGetColor( 0 );

        //    Call a method within our graphics canvas and tell it to set the background color.
        theBackdropCanvas.doSetBackgroundColor(
                menuColor[ theColor ] );

        //    Our applet should draw everything it knows about the first time through.
        repaint();
    }

    //    Haven't made use of this yet.
    public void start()
    {
    }

    //    Stop loading/running when requested.
    public void stop()
    {
        myDemo.doDestroy();
        System.exit( 0 );
    }

    //    Graceful exit when requested.
    public void doDestroy()
    {
        theToolPalette.hide();
        theBackdropCanvas.hide();
        theNewButtonFrame.hide();
        System.exit( 0 );
    }

    //    Create a panel/rectangle object upon request from the tool palette.
    public boolean doAddRect()
    {
        boolean        doRepaint = false;
        int                theColor;
        String        theNewString = new String( "" );

        theColor = theToolPalette.doGetColor( 1 );
        theBackdropCanvas.doChangeColor( 1, theColor );

        theColor = theToolPalette.doGetColor( 2 );
        theBackdropCanvas.doChangeColor( 2, theColor );

        doRepaint = theBackdropCanvas.doAddDecafObject( 0,
                theNewString );

        if ( doRepaint )
            theBackdropCanvas.repaint();

        return true;
    }

    //    Setup our dialog that will request a button label from the user.
    public boolean doCreateButtonFrame()
    {
        boolean        doRepaint = false;
        boolean        dummy = false;

        dummy = theNewButtonFrame.doSetupDefaults();
        theNewButtonFrame.show();

        if ( doRepaint )
            repaint();

        return true;
    }

    //    Add a "button" object upon request from the tool palette.
    public boolean doAddButton( String theNewString )
    {
        boolean        doRepaint = false;
        int                theColor;

        theColor = theToolPalette.doGetColor( 3 );
        theBackdropCanvas.doChangeColor( 3, theColor );

        theColor = theToolPalette.doGetColor( 4 );
        theBackdropCanvas.doChangeColor( 4, theColor );

        doRepaint = theBackdropCanvas.doAddDecafObject( 1,
                theNewString );

        if ( doRepaint )
            theBackdropCanvas.repaint();

        return true;
    }

    //    Change the color for one or more of our objects upon request from the tool palette.
    public boolean doChangeColor( int theItem, int theColor )
    {
        boolean        doRepaint = false;

        doRepaint = theBackdropCanvas.doChangeColor( theItem,
                theColor );

        if ( doRepaint )
            theBackdropCanvas.repaint();

        return true;
    }

    //    Delete one selected item upon request from the tool palette.
    public boolean doDeleteItem()
    {
        boolean        doRepaint = false;

        doRepaint = theBackdropCanvas.doDeleteDecafObject();

        if ( doRepaint )
            theBackdropCanvas.repaint();

        return true;
    }

    //    Change the background color for our drawing area on request from the tool palette.
    public boolean doSetBackColor( int theColor )
    {
        Color        menuColor[] = {     Color.black, Color.green,
                                                        Color.pink, Color.blue,
                                                        Color.lightGray, Color.red,
                                                        Color.cyan, Color.magenta,
                                                        Color.white, Color.darkGray,
                                                        Color.orange, Color.yellow,
                                                        Color.gray };

        theBackdropCanvas.doSetBackgroundColor( menuColor[
                theColor ] );

        theBackdropCanvas.repaint();

        return true;
    }

}