[Android] AlertDialog

public class JoinActivity extends AppCompatActivity {


    /* 키보드 내리기 */
    InputMethodManager imm;


    /* 다이얼로그 */
    private AlertDialog dialog;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this, R.layout.activity_join);

        /* 툴바 이름 세팅 */
        setSupportActionBar(binding.toolbar);
        getSupportActionBar().setTitle("");

        /* 키보드 내리기 */
        imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
        binding.linear.setOnClickListener(v -> hideKeyboard());

        /* cancel 버튼 누르면 화면 종료 */
        binding.cancelBtn.setOnClickListener(v -> finish());

     

        /* 다음 버튼 */
        binding.nextBtn.setOnClickListener(v -> {
            if(binding.memberId.getText().toString().trim().equals("")) {
                //Toast.makeText(getApplicationContext(), R.string.IdInPutMsg, Toast.LENGTH_SHORT).show();
                AlertDialog.Builder builder = new AlertDialog.Builder(JoinActivity.this);
                dialog = builder.setMessage(getText(R.string.IdInPutMsg))
                        .setPositiveButton("확인", null)
                        .create();
                dialog.show();
                return;
            }
            if(!validate) {
                //Toast.makeText(getApplicationContext(), R.string.IdCheckMsg, Toast.LENGTH_SHORT).show();
                AlertDialog.Builder builder = new AlertDialog.Builder(JoinActivity.this);
                dialog = builder.setMessage(getText(R.string.IdCheckMsg))
                        .setPositiveButton("확인", null)
                        .create();
                dialog.show();
                return;
            }
            if(binding.password.getText().toString().trim().equals("") || binding.passwordCheck.getText().toString().trim().equals("") ||
                    binding.memberName.getText().toString().trim().equals("") || binding.email.getText().toString().trim().equals("") ||
                    binding.phone.getText().toString().trim().equals("") || binding.address.getText().toString().trim().equals("")) {
                //Toast.makeText(getApplicationContext(), R.string.NoEmptyMsg, Toast.LENGTH_SHORT).show();
                AlertDialog.Builder builder = new AlertDialog.Builder(JoinActivity.this);
                dialog = builder.setMessage(getText(R.string.NoEmptyMsg))
                        .setPositiveButton("확인", null)
                        .create();
                dialog.show();
                return;
            }
            if(! binding.password.getText().toString().trim().equals(binding.passwordCheck.getText().toString().trim())) {
                //Toast.makeText(getApplicationContext(), R.string.NoMatchPw, Toast.LENGTH_SHORT).show();
                AlertDialog.Builder builder = new AlertDialog.Builder(JoinActivity.this);
                dialog = builder.setMessage(getText(R.string.NoMatchPw))
                        .setPositiveButton("확인", null)
                        .create();
                dialog.show();
                return;
            }
            if(! binding.agreeCheckBox.isChecked()) {
                //Toast.makeText(getApplicationContext(), R.string.AgreeMsg, Toast.LENGTH_SHORT).show();
                AlertDialog.Builder builder = new AlertDialog.Builder(JoinActivity.this);
                dialog = builder.setMessage(getText(R.string.AgreeMsg))
                        .setPositiveButton("확인", null)
                        .create();
                dialog.show();
                return;
            }
        });


        // 미구현 메시지
        binding.viewAllTerms.setOnClickListener(v->Toast.makeText(getApplicationContext(), R.string.NoFunctionMsg, Toast.LENGTH_SHORT).show());


    }   // onCreate 끝


    /* 키보드 내리기 */
    private void hideKeyboard()
    {
        imm.hideSoftInputFromWindow(binding.memberId.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.password.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.passwordCheck.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.memberName.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.email.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.address.getWindowToken(), 0);
        imm.hideSoftInputFromWindow(binding.phone.getWindowToken(), 0);
    }


    @Override
    protected void onStop() {
        super.onStop();
        if(dialog != null){
            dialog.dismiss();
            dialog = null;
        }
    }


}