Difference between revisions of "Teams Winter 2011/team1/Android/Implement Delete Option"

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=== 5. Implement Delete Option ===
 
=== 5. Implement Delete Option ===
 
5.1. In the <code>ContactList</code> class add the following lines to the <code>onOptionsItemSelected</code> method:
 
5.1. In the <code>ContactList</code> class add the following lines to the <code>onOptionsItemSelected</code> method:
  <pre>
+
  <source lang="java">
 
   case R.id.item2:
 
   case R.id.item2:
 
             Student deleteStudent = (Student)contactsList.getSelectedItem();
 
             Student deleteStudent = (Student)contactsList.getSelectedItem();
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             }
 
             }
 
             break;
 
             break;
  </pre>
+
  </source>
 
5.2. Add the method to generate the dialog window to alert if no contact has been selected:
 
5.2. Add the method to generate the dialog window to alert if no contact has been selected:
  <pre>
+
  <source lang="java">
 
   public void showDialog(String message){
 
   public void showDialog(String message){
 
         AlertDialog alertDialog = new AlertDialog.Builder(this).create();
 
         AlertDialog alertDialog = new AlertDialog.Builder(this).create();
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         alertDialog.show();
 
         alertDialog.show();
 
     }
 
     }
  </pre>
+
  </source>
 
5.3. Run the application, select one student from the list, press menu and select "Delete Student":<br/>
 
5.3. Run the application, select one student from the list, press menu and select "Delete Student":<br/>
 
[[Image: A_delete1.png | 450px]]<br/>
 
[[Image: A_delete1.png | 450px]]<br/>

Latest revision as of 11:19, 28 March 2011

5. Implement Delete Option

5.1. In the ContactList class add the following lines to the onOptionsItemSelected method:

   case R.id.item2:
            Student deleteStudent = (Student)contactsList.getSelectedItem();
            if (deleteStudent != null){
            studentList.removeElement(deleteStudent);           
            displayData(studentList);
            } else {
                showDialog("No contact was selected!");               
            }
            break;

5.2. Add the method to generate the dialog window to alert if no contact has been selected:

  public void showDialog(String message){
        AlertDialog alertDialog = new AlertDialog.Builder(this).create();
        alertDialog.setMessage(message);
        alertDialog.show();
    }

5.3. Run the application, select one student from the list, press menu and select "Delete Student":
A delete1.png
5.4. The list should get updated:
A delete2.png
5.5. Run the application again, but this time don't select any student and try to execute the delete option. You should get the following message:
A view2.png