1 Java Swing Application Flow By mr. Hanley 11/7/2005

2 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

3 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); }

4 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

5 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

6 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));

7 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));

8 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));

9 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));

10 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");

11 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);

12 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); }

13 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

14 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