Question

DataBaseHandler类中的My Update方法

    public void updateProject(Project project){
         SQLiteDatabase db = this.getWritableDatabase();
         ContentValues values = new ContentValues();
         values.put(PROJECT_NAME, project.getName()); // Contact Name
         values.put(PROJECT_DESCRIPTION, project.getDescription()); // Contact Phone
         values.put(CLIENT_NAME, project.getClient_name());
         values.put(LOCATION, project.getLocation());
         String where = PROJECT_ID + " = ? ";       
         String [] value = { String.valueOf(project.getProject_id()) };
         try{
             int count = db.update(TABLE_PROJECT, values, where , value);
             Log.d(LOG_TAG, "Updated rows -> " + count);
         }catch (Exception e) {
            e.printStackTrace();
        }
        db.close();
    }
}

java bean类

public class Project implements Serializable{

    private static final long serialVersionUID = 1L;
    private int project_id;
    private String name;
    private String description;
    private String client_name;
    private String location;

    public Project(){

    }

    public Project(int project_id, String name, String client_name,String description, String location){
        this.project_id = project_id;
        this.name = name;
        this.description = description;
        this.client_name = client_name;
        this.location = location;
    }

    public int getProject_id() {
        return project_id;
    }

    public void setProject_id(int project_id) {
        this.project_id = project_id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getClient_name() {
        return client_name;
    }

    public void setClient_name(String client_name) {
        this.client_name = client_name;
    }

    public String getLocation() {
        return location;
    }

    public void setLocation(String location) {
        this.location = location;
    }

}

从列表视图添加和更新项目项的活动

public class AddProjectActivity extends Activity implements Serializable{

    private static final long serialVersionUID = 1L;
    private MenuItem saveItem;
    private DatabaseHandler dbHelper;
    private static final String TITLE = "Add Project";
    public boolean isEdit = false;
    private static final String LOG_TAG = "debugger";
    private Project editedProject;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.add_project);
        setTitle(TITLE);
        dbHelper = DatabaseHandler.getInstance(this);           

        //get intent from Project Fragment when project is edited
        Intent intent = getIntent();
        if(intent.hasExtra(IntentConstants.PROJECT_ITEM)){
            Project project = (Project) intent.getSerializableExtra(IntentConstants.PROJECT_ITEM);
            if(project != null){
                this.isEdit = true;
                setEditedProject(project);
                setProjectData(project);
            }
        }
    }          



    private void setProjectData(Project project){
        EditText projectName = (EditText) findViewById(R.id.editTextProjectName);
        projectName.setText(project.getName());
        EditText clientName = (EditText) findViewById(R.id.editTextProjectClient);
        clientName.setText(project.getClient_name());
        EditText projectDesc = (EditText) findViewById(R.id.editTextProjectDesc);
        projectDesc.setText(project.getDescription());
        EditText projectLocation = (EditText) findViewById(R.id.editTextProjectLocation);
        projectLocation.setText(project.getLocation());
    }



@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
      case R.id.saveButton:
           if(isEdit == true){
              updateProject();
           }else{
              saveProject();
           }
           finish();
        break;
     case R.id.cancelButton:
        finish();
        break;
     default:
        break;
    }
 return true;
}

    private void updateProject(){
      dbHelper.updateProject(getProjectData(getEditedProject()));
    }

    public boolean isEdit() {
        return isEdit;
    }

    public void setEdit(boolean isEdit) {
        this.isEdit = isEdit;
    }

    private Project getProjectData(Project newProject){
        EditText projectName = (EditText) findViewById(R.id.editTextProjectName);
        String project = projectName.getText().toString();
        EditText clientName = (EditText) findViewById(R.id.editTextProjectClient);
        String client = clientName.getText().toString();
        EditText projectDesc = (EditText) findViewById(R.id.editTextProjectDesc);
        String description = projectDesc.getText().toString();
        EditText projectLocation = (EditText) findViewById(R.id.editTextProjectLocation);
        String location = projectLocation.getText().toString();

        newProject.setName(project);
        newProject.setClient_name(client);
        newProject.setDescription(description);
        newProject.setLocation(location);
        return newProject;
    }

    public Project getEditedProject() {
        return editedProject;
    }

    public void setEditedProject(Project editedProject) {
        this.editedProject = editedProject;
    }

}

我的ListFragment方法处理listview项目的点击。它使用AddProjectActivity

将数据传递给Intent

@Override
    public void onListItemClick(ListView l, View v, int position, long id) {
        super.onListItemClick(l, v, position, id);
        if(dbHelper != null){
            Project project = (Project) this.getListAdapter().getItem(position);
            Intent intent = new Intent(getActivity(), AddProjectActivity.class);
            intent.putExtra(IntentConstants.PROJECT_ITEM, project);
            startActivity(intent);
            this.isEdit = true;
        }
    }

我遇到的问题是当listview项目被用户编辑和更新时，它永远不会在数据库中更新。 update方法返回的rowcount始终为零。

我无法解决此问题。

有人可以帮忙吗。

Answer 1

我发现了这个问题。我没有在ListView中设置Project对象的id。所以id永远不会匹配，也没有更新。

Android更新数据库记录始终返回零

1 个答案: