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=== 7. Implement Delete Student option ===
7.1. In the <code>ViewStudentApp</code> implement <code>DeleteCommandHandler</code> by adding anonymous class:
<presource lang="java">
deleteItem.setCommand(new Command(new CommandHandler(){
public void execute(ReadOnlyCommandMetadata metadata, Object context) {
}
}));
</presource>
7.2. Add the <code>deleteElement()</code> method to the <code>StudentList</code> class:
<presource lang="java">
void deleteElement(Object element) {
doRemove(element);
}
</presource>
7.3. Run the application, select one student and select "'''Delete Student'''" from the menu:<br/>
[[Image: BB_delete1.png | 300px]]<br/>
[[Image: BB_delete2.png | 300px]]<br/>
7.5. Select "'''Yes'''" Option. The dialog window comes up acknowledging that student is deleted:<br/>
[[Image: BB_delete3.png | 300px]]<br/>7.6. Add "''Delete Student''" as option in view screen. Change the one argument constructor of the anonymous class to two argument constructor: <source lang="java"> InfoScreen(final Student student, final StudentList studentList) { } </source>7.7. Add <code>MenuItem</code> to this screen menu and implement <code>CommandHandler</code>: <source lang="java"> MenuItem deleteItem = new MenuItem(new StringProvider("Delete Student"), 400, 4); deleteItem.setCommand(new Command(new CommandHandler(){ public void execute(ReadOnlyCommandMetadata metadata, Object context) { if (student != null) { String[] selections = {"Yes","Cancel"}; Dialog deleteDialog = new Dialog("Are you sure you want to delete " + student.getName() + "?", selections, null, 0, null); // Display the dialog and deletes the element from the list if(deleteDialog.doModal() == 0) { studentList.deleteElement(student); Dialog.alert(student.getName() + " has been deleted!"); close(); } } } })); addMenuItem(deleteItem); </source>7.8. Run the application, select a student and inside the View Screen go to the menu and select "'''Delete Student'''": <br/>[[Image: BB_delete4.png | 300px]]<br/>7.9. Repeat the same steps as for the Main Screen. When you are done you should be redirected to Main Screen.
