android - SQLite 数据库列不会使用 Update 方法进行更新

Question

我的应用程序使用 SQLite 数据库，我想将来自多个 Activity 的数据保存到一个表中。在第一个 Activity 中，我使用 add 方法在表中创建一行。在下一个 Activity 中，我使用 update 方法更新现有行中的列。
我使用 DB Browser for SQLite 应用程序检查我的数据库，它显示我从第二个 Activity 中保存的数据不在数据库中(空)。不知道是什么问题。
这是我的类(class):
SQLiteHelper :

    public class SQLiteHelper extends SQLiteOpenHelper implements ProjectDAO {

    public SQLiteHelper(Context context) {
        super(context, "my_db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        try {
            db.execSQL("CREATE TABLE tbl_project_info (id INTEGER PRIMARY KEY," +
                    "name TEXT," +
                    "company_name TEXT," +
                    "address TEXT," +
                    "length1 TEXT," +
                    "length2 TEXT," +
                    "length3 TEXT," +
                    "length4 TEXT," +
                    "length5 TEXT," +
                    "diameter1 Text,"+
                    "diameter2 Text,"+
                    "diameter3 Text,"+
                    "diameter4 Text,"+
                    "diameter5 Text)");
        } catch (SQLiteException e) {
            Log.e("SQLITE", "onCreate: " + e.toString());
        }

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }

    @Override
    public boolean addProject(Project project) {
        SQLiteDatabase db = getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put("name", project.getName());
        contentValues.put("company_name", project.getCompany_name());
        contentValues.put("address", project.getAddress());
        contentValues.put("length1",project.getLength1());
        contentValues.put("length2",project.getLength2());
        contentValues.put("length3",project.getLength3());
        contentValues.put("length4",project.getLength4());
        contentValues.put("length5",project.getLength5());
        contentValues.put("diameter1",project.getDiameter1());
        contentValues.put("diameter2",project.getDiameter2());
        contentValues.put("diameter3",project.getDiameter3());
        contentValues.put("diameter4",project.getDiameter4());
        contentValues.put("diameter5",project.getDiameter5());
        long result = db.insert("tbl_project_info", null, contentValues);
        db.close();
        return result != -1;
    }

    @Override
    public int getProjectsCount() {
        SQLiteDatabase db = getReadableDatabase();
        Cursor cursor = db.rawQuery("SELECT * FROM tbl_project_info", null);
        int count = cursor.getCount();
        cursor.close();
        db.close();
        return count;
    }

    @Override
    public boolean updateProject(Project project) {
        SQLiteDatabase db = getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put("length1",project.getLength1());
        contentValues.put("length2",project.getLength2());
        contentValues.put("length3",project.getLength3());
        contentValues.put("length4",project.getLength4());
        contentValues.put("length5",project.getLength5());
        contentValues.put("diameter1",project.getDiameter1());
        contentValues.put("diameter2",project.getDiameter2());
        contentValues.put("diameter3",project.getDiameter3());
        contentValues.put("diameter4",project.getDiameter4());
        contentValues.put("diameter5",project.getDiameter5());
        db.update("tbl_project_info",contentValues,"id = ?", new String[]{String.valueOf(project.getId())});
        db.close();
        return true;
    }

    @Override
    public List<Project> getAllProjects() {
        List<Project> projects = new ArrayList<>();
        SQLiteDatabase db = getReadableDatabase();
        Cursor cursor = db.rawQuery("SELECT * FROM tbl_project_info", null);
        if (cursor.moveToFirst()) {
            do {
                Project project = new Project();
                project.setName(cursor.getString(0));
                project.setCompany_name(cursor.getString(1));
                project.setAddress(cursor.getString(2));
                projects.add(project);
            } while (cursor.moveToNext());
        }
        return projects;
    }
}

新项目 Activity :

public class NewProjectActivity extends AppCompatActivity {
    private ProjectDAO projectDAO;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_new_project);
        projectDAO = DBInjector.provideProjectDao(this);
        setupViews();
    }

    private void setupViews() {
        final EditText projectNameET = findViewById(R.id.et_newProject_projectName);
        final EditText companyNameET = findViewById(R.id.et_newProject_companyName);
        final EditText addressET = findViewById(R.id.et_newProject_address);
        Button saveInfoBTN = findViewById(R.id.btn_newProject_saveInfo);

        saveInfoBTN.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (projectNameET.length() > 0) {
                    if (companyNameET.length() > 0) {
                        if (addressET.length() > 0) {
                            Project project = new Project();
                            project.setName(projectNameET.getText().toString());
                            project.setCompany_name(companyNameET.getText().toString());
                            project.setAddress(addressET.getText().toString());
                            if (projectDAO.addProject(project)){
                                Toast.makeText(NewProjectActivity.this, "Success", Toast.LENGTH_SHORT).show();
                            }else {
                                Toast.makeText(NewProjectActivity.this, "Failed", Toast.LENGTH_SHORT).show();
                            }
                        }
                    }
                }

                Intent intent = new Intent(NewProjectActivity.this,MainActivity.class);
                startActivity(intent);
                }
            });
        }
    }  

主要 Activity :

public class MainActivity extends AppCompatActivity {
    private ProjectDAO projectDAO;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        projectDAO = DBInjector.provideProjectDao(this);

        final EditText lengthET1 = findViewById(R.id.et_main_length1);
        final EditText lengthET2 = findViewById(R.id.et_main_length2);
        final EditText lengthET3 = findViewById(R.id.et_main_length3);
        final EditText lengthET4 = findViewById(R.id.et_main_length4);
        final EditText lengthET5 = findViewById(R.id.et_main_length5);
        final EditText diameterET1 = findViewById(R.id.et_main_diameter1);
        final EditText diameterET2 = findViewById(R.id.et_main_diameter2);
        final EditText diameterET3 = findViewById(R.id.et_main_diameter3);
        final EditText diameterET4 = findViewById(R.id.et_main_diameter4);
        final EditText diameterET5 = findViewById(R.id.et_main_diameter5);

        Button calculateButton = findViewById(R.id.btn_main_calculate);
        calculateButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                float Le1 = 0;
                if (lengthET1.length() > 0) {
                    String L1 = lengthET1.getText().toString();
                    Le1 = Float.parseFloat(L1);
                }
                float Di1 = 0;
                if (diameterET1.length() > 0) {
                    String D1 = diameterET1.getText().toString();
                    Di1 = Float.parseFloat(D1);
                }
                float Le2 = 0;
                if (lengthET2.length() > 0) {
                    String L2 = lengthET2.getText().toString();
                    Le2 = Float.parseFloat(L2);
                }
                float Di2 = 0;
                if (diameterET2.length() > 0) {
                    String D2 = diameterET2.getText().toString();
                    Di2 = Float.parseFloat(D2);
                }
                float Le3 = 0;
                if (lengthET3.length() > 0) {
                    String L3 = lengthET3.getText().toString();
                    Le3 = Float.parseFloat(L3);
                }
                float Di3 = 0;
                if (diameterET3.length() > 0) {
                    String D3 = diameterET3.getText().toString();
                    Di3 = Float.parseFloat(D3);
                }
                float Le4 = 0;
                if (lengthET4.length() > 0) {
                    String L4 = lengthET4.getText().toString();
                    Le4 = Float.parseFloat(L4);
                }
                float Di4 = 0;
                if (diameterET4.length() > 0) {
                    String D4 = diameterET4.getText().toString();
                    Di4 = Float.parseFloat(D4);
                }
                float Le5 = 0;
                if (lengthET5.length() > 0) {
                    String L5 = lengthET5.getText().toString();
                    Le5 = Float.parseFloat(L5);
                }
                float Di5 = 0;
                if (diameterET5.length() > 0) {
                    String D5 = diameterET5.getText().toString();
                    Di5 = Float.parseFloat(D5);
                }

                final float Surface1 = (float) (Le1 * Di1 * Math.PI);
                final float Surface2 = (float) (Le2 * Di2 * Math.PI);
                final float Surface3 = (float) (Le3 * Di3 * Math.PI);
                final float Surface4 = (float) (Le4 * Di4 * Math.PI);
                final float Surface5 = (float) (Le5 * Di5 * Math.PI);

                final float Surface = Surface1 + Surface2 + Surface3 + Surface4 + Surface5;

                Intent intent = new Intent(MainActivity.this, IntensityActivity.class);
                if (Surface == 0) {
                    Toast.makeText(MainActivity.this, "No numbers are entered", Toast.LENGTH_SHORT).show();
                } else {
                    intent.putExtra("Result", Surface);
                    startActivity(intent);
                }
                PersonalInfoSharedPrefManager manager = new PersonalInfoSharedPrefManager(MainActivity.this);
                manager.setSuface(Surface);

                Project project = new Project();

                project.setLength1(lengthET1.getText().toString());
                project.setDiameter1(diameterET1.getText().toString());

                project.setLength2(lengthET2.getText().toString());
                project.setDiameter2(diameterET2.getText().toString());

                project.setLength3(lengthET3.getText().toString());
                project.setDiameter3(diameterET3.getText().toString());

                project.setLength4(lengthET4.getText().toString());
                project.setDiameter4(diameterET4.getText().toString());

                project.setLength5(lengthET5.getText().toString());
                project.setDiameter5(diameterET5.getText().toString());

                projectDAO.updateProject(project);
            }
        });
    }
}

Answer 1

在 MainActivity 中，您应该设置您的项目 ID 以进行更新:

 Project project = new Project();
 project.setId(yourIdValue);