how to use the built-in contact manager in my app to view contacts

Question

I mean that I don't want to create my own design and instead use the built-in design and view of contact manager that looks clean.

Answer 1

You can set an Event on Button click by setting an OnClickListener on the Button with the following code, and use Intent to call ContactPicker activity:

button.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
             Intent intent= new Intent(Intent.ACTION_PICK,  Contacts.CONTENT_URI);

    startActivityForResult(intent, PICK_CONTACT);

        }
    });

and in onActivityResult() process the contact uri to load details of contact.

@Override
public void onActivityResult(int reqCode, int resultCode, Intent data) {
  super.onActivityResult(reqCode, resultCode, data);

switch (reqCode) {
case (PICK_CONTACT) :
  if (resultCode == Activity.RESULT_OK) {
    Uri contactData = data.getData();
    Cursor c =  managedQuery(contactData, null, null, null, null);
    if (c.moveToFirst()) {
      String name = c.getString(c.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
      // TODO Fetch other Contact details as you want to use

    }
  }
  break;
}
}