My first activity:
btnResetSt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
edtStId.setText("");
edtStName.setText("");
edtStDoB.setText("");
edtStEmail.setText("");
edtStPhone.setText("");
edtStAddress.setText("");
edtStBatch.setText("");
Toast.makeText(AddStudent.this,students.size()+"",Toast.LENGTH_LONG).show();
Intent intent = new Intent(AddStudent.this, StudentManage.class);
intent.putExtra("StudentList",students);
startActivity(intent);
}
});
Function to add Student:
btnAddSt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Student st = new Student();
st.setStdId(edtStId.getText().toString());
st.setStdName(edtStName.getText().toString());
st.setStdDoB(edtStDoB.getText().toString());
st.setStdEmail(edtStEmail.getText().toString());
st.setStdPhone(edtStPhone.getText().toString());
st.setStdAddress(edtStAddress.getText().toString());
st.setStdBatch(edtStBatch.getText().toString());
students.add(st);
}
});
After add a student to ArrayList, i want passing it throught btnResetSt use Intent.
Here is my Second activity :
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_student_manage);
Anhxa();
Intent intent = getIntent();
if (intent.getSerializableExtra("students")!=null) {
students = (ArrayList<Student>) intent.getSerializableExtra("students");
stAdt = new StudentAdapter(this, R.layout.student_line, students);
lstvSt.setAdapter(stAdt);
stAdt.notifyDataSetChanged();
}else {Toast.makeText(this,"Null",Toast.LENGTH_LONG).show();}
}
I use a Toast.makeText to check result of intent.getSerializableExtra and it realy Null so i can't display my list in second activity to List View. Can anybody say where i am wrong?
You're getting the wrong extra. You need to get the extra with the key StudentList
.
So it must be:
students = (ArrayList<Student>) intent.getSerializableExtra("StudentList");
To prevent the same mistake, use a static key in the target Activity. Something like this:
public class SecondActivity extends Activity {
public static final String STUDENT_LIST_EXTRA = "StudentList";
...
}
So, you can use the following to put the extra:
intent.putExtra(SecondActivity.STUDENT_LIST_EXTRA, students);
And, use the following to get the extra:
students = (ArrayList<Student>) intent.getSerializableExtra(STUDENT_LIST_EXTRA);
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