Java Swing Application Flow By mr. Hanley 11/7/2005
How does a swing app flow? • In our Swing Applications, we have used two files, an app file and a frame file • Let’s take the SnowFall Assignment as an Example
How does a swing app flow? • 1. A java application looks for a main method • import java.awt.*; • import javax.swing.*; • public class Proj2App { • public static void main(String[] args) { • Proj2Frame p = new Proj2Frame(); • p.setSize(500,400); • p.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); • p.setTitle("Project 2 Basic Mathematical Problems"); • p.setVisible(true); • }
How does a swing app flow? • 2. When the first line of the main is encountered, a new Proj2Frame object is created • Proj2Frame p = new Proj2Frame(); • 3. Since we are creating a new object, a constructor is called • A constructor is a method with the same name of the class
How does a swing app flow? • public Proj2Frame() { • try { • jbInit(); • } • catch (Exception ex) { • ex.printStackTrace(); • } • } • 4. All global variables are created and initialized to either 0 or null • 5. The constructor calls a method called jbInit, which stands for jbuilder initialize
How does a swing app flow? • private void jbInit() throws Exception { • this.getContentPane().setLayout(null); • tabPane.setBounds(new Rectangle(30, 20, 348, 273)); • snowAvgPAN.setLayout(null); • sodaCompPAN.setLayout(null); • areaCirPAN.setLayout(null); • areaLBL.setText("Area"); • areaLBL.setBounds(new Rectangle(24, 93, 90, 24)); • areaTF.setEnabled(false); • areaTF.setEditable(false); • areaTF.setText(""); • areaTF.setBounds(new Rectangle(23, 121, 90, 25)); • cirLBL.setText("Circumference"); • cirLBL.setBounds(new Rectangle(25, 164, 90, 24));
How does a swing app flow? • cirTF.setEditable(false); • cirTF.setBounds(new Rectangle(23, 190, 90, 25)); • radiusLBL.setText("Radius"); • radiusLBL.setBounds(new Rectangle(24, 21, 90, 24)); • radiusTF.setBounds(new Rectangle(23, 50, 90, 25)); • acBUT.setBounds(new Rectangle(154, 47, 90, 29)); • acBUT.setText("Find A+C"); • cost2lTF.setEditable(false); • cost2lTF.setText(""); • cost2lTF.setBounds(new Rectangle(162, 42, 112, 26)); • price6packLBL.setText("Price in $ for a 6 pack"); • price6packLBL.setBounds(new Rectangle(21, 82, 145, 18)); • cost6packTF.setEditable(false); • cost6packTF.setBounds(new Rectangle(161, 107, 112, 26)); • cost2lLBL.setText("Cost in $/L"); • cost2lLBL.setBounds(new Rectangle(161, 16, 145, 18)); • price2lTF.setBounds(new Rectangle(23, 43, 112, 26)); • cost6packLBL.setText("Cost in $/L"); • cost6packLBL.setBounds(new Rectangle(160, 81, 145, 18));
How does a swing app flow? • price2lLBL.setText("Price in $ for 2 Liter"); • price2lLBL.setBounds(new Rectangle(22, 17, 145, 18)); • price6packTF.setText(""); • price6packTF.setBounds(new Rectangle(22, 108, 112, 26)); • twolRB.setText(""); • twolRB.setBounds(new Rectangle(295, 40, 107, 27)); • sixPackRB.setText("jRadioButton1"); • sixPackRB.setBounds(new Rectangle(295, 105, 16, 19)); • includeDepCBX.setText(""); • includeDepCBX.setBounds(new Rectangle(20, 154, 19, 14)); • includeDepLBL.setText("Include Deposit"); • includeDepLBL.setBounds(new Rectangle(48, 152, 100, 18)); • compareBUT.setBackground(Color.orange); • compareBUT.setBounds(new Rectangle(160, 148, 97, 26)); • compareBUT.setActionCommand("compBUT"); • compareBUT.setText("Compare"); • monTF.setText(""); • monTF.setBounds(new Rectangle(21, 32, 75, 24)); • monLBL.setText("Snow Monday"); • monLBL.setBounds(new Rectangle(17, 9, 88, 20));
How does a swing app flow? • tuesTF.setBounds(new Rectangle(20, 85, 75, 24)); • tuesLBL.setText("Snow Tuesday"); • tuesLBL.setBounds(new Rectangle(17, 62, 88, 20)); • wedTF.setBounds(new Rectangle(20, 143, 75, 24)); • wedLBL.setText("Snow Wednesday"); • wedLBL.setBounds(new Rectangle(18, 120, 106, 20)); • thurTF.setBounds(new Rectangle(18, 197, 75, 24)); • thurLBL.setText("Snow Thursday"); • thurLBL.setBounds(new Rectangle(20, 174, 110, 20)); • friTF.setBounds(new Rectangle(165, 32, 75, 24)); • friLBL.setText("Snow Friday"); • friLBL.setBounds(new Rectangle(166, 8, 88, 20)); • avgBUT.setBounds(new Rectangle(160, 68, 90, 74)); • avgBUT.setIcon(flakeIC); • avgBUT.setText("Average"); • avgTF.setEditable(false); • avgTF.setBounds(new Rectangle(164, 195, 75, 24));
How does a swing app flow? • avgLBL.setText("Average"); • avgLBL.setBounds(new Rectangle(166, 172, 88, 20)); • this.getContentPane().add(tabPane); • snowAvgPAN.add(tuesLBL); • snowAvgPAN.add(tuesTF); • snowAvgPAN.add(monTF); • snowAvgPAN.add(wedLBL); • snowAvgPAN.add(wedTF); • snowAvgPAN.add(thurLBL); • snowAvgPAN.add(thurTF); • snowAvgPAN.add(friTF); • snowAvgPAN.add(friLBL); • snowAvgPAN.add(avgBUT); • snowAvgPAN.add(avgTF); • snowAvgPAN.add(avgLBL); • snowAvgPAN.add(monLBL); • tabPane.add(areaCirPAN, "Area/Cir");
How does a swing app flow? • areaCirPAN.add(areaTF); • areaCirPAN.add(radiusTF); • areaCirPAN.add(cirLBL); • areaCirPAN.add(radiusLBL); • areaCirPAN.add(cirTF); • areaCirPAN.add(areaLBL); • areaCirPAN.add(acBUT); • sodaCompPAN.add(price6packLBL); • sodaCompPAN.add(price2lTF); • sodaCompPAN.add(price2lLBL); • sodaCompPAN.add(cost2lLBL); • sodaCompPAN.add(cost6packLBL); • sodaCompPAN.add(cost6packTF); • sodaCompPAN.add(cost2lTF); • sodaCompPAN.add(price6packTF);
How does a swing app flow? • sodaCompPAN.add(twolRB); • sodaCompPAN.add(sixPackRB); • sodaCompPAN.add(includeDepCBX); • sodaCompPAN.add(includeDepLBL); • sodaCompPAN.add(compareBUT); • tabPane.add(sodaCompPAN, "Compare Sodas"); • tabPane.add(snowAvgPAN, "Snow Fall"); • acBUT.addActionListener(this); • compareBUT.addActionListener(this); • avgBUT.addActionListener(this); • }
How does a swing app flow? • 6, Now that the initialize method is done, the app sends various messages to the frame • P.setsize • P.setTitle • P.setVisible • P.setDefaultCloseOp
How does a swing app flow? • 7. The application waits for user initiated events • 8. These trigger the actionPerformed method • 9. The app file is essentially done at this point in time
