MainActivity.java

package com.example.f55123084;

import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private EditText edtWidth, edtHeight, edtLength;
    private Button btnCalculate;
    private TextView tvResult;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        edtWidth = findViewById(R.id.edt_width);
        edtHeight = findViewById(R.id.edt_height);
        edtLength = findViewById(R.id.edt_length);
        btnCalculate = findViewById(R.id.btn_calculate);
        tvResult = findViewById(R.id.tv_result);
        btnCalculate.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        if (view.getId() == R.id.btn_calculate) {
            String inputLength = edtLength.getText().toString().trim();
            String inputWidth = edtWidth.getText().toString().trim();
            String inputHeight = edtHeight.getText().toString().trim();
            boolean isEmptyFields = false;
            if (TextUtils.isEmpty(inputLength)) {
                isEmptyFields = true;
                edtLength.setError("Field ini tidak boleh kosong");
            }
            if (TextUtils.isEmpty(inputWidth)) {
                isEmptyFields = true;
                edtWidth.setError("Field ini tidak boleh kosong");
            }
            if (TextUtils.isEmpty(inputHeight)) {
                isEmptyFields = true;
                edtHeight.setError("Field ini tidak boleh kosong");
            }
            if (!isEmptyFields) {
                double volume = Double.parseDouble(inputLength) * Double.parseDouble(inputWidth) * Double.parseDouble(inputHeight);
                tvResult.setText(String.valueOf(volume));
            }

        }
    }
}