【Android】家庭记账本手机版开发报告四

一、说在前面

昨天	对界面显示和逻辑结构进行完善
今天	1、添加菜单（查询、清除所有等） 2、使用滑动删除
问题	1、在做查询时获取SearchView时引 入包错误经过长时间的尝试后才修正 2、滑动删除的撤销问题。

二、菜单设计

1、创建菜单资源

2、添加两个MenuItem 和一个搜索标志

3、将菜单设置在AccountRecordFragment 的界面上，并关联数据库

@Override
    public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        inflater.inflate(R.menu.show_menu,menu);
        SearchView searchView = (SearchView) menu.findItem(R.id.app_bar_search).getActionView();
        searchView.setMaxWidth(1000);
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }
            @Override
            public boolean onQueryTextChange(String newText) {
                String type = newText.trim();
                findAccountRecord.removeObservers(requireActivity());
                findAccountRecord = accountRecordViewModel.getAcountRecordByType(type);
                findAccountRecord.observe(requireActivity(), new Observer<List<AccountRecord>>() {
                    @Override
                    public void onChanged(List<AccountRecord> accountRecords) {
                        allAccountRecord = accountRecords;
                        myAdpter.setAllAccountRecords(accountRecords);
                        myAdpter.notifyDataSetChanged();
                    }
                });
                return true;
            }
        });
    }

4、查询数据库的相关修改

1）dao层

@Query("SELECT * From ACCOUNTRECORD WHERE cost_type LIKE :type ORDER BY ID DESC")
    LiveData<List<AccountRecord>> getAccountRecordLiveByType (String type);

2）“工厂”

public LiveData<List<AccountRecord>> getAcountRecordByType(String type) {
        return accountRecordDao.getAccountRecordLiveByType("%"+type+"%");//实现模糊查询
    }

3）ViewModel

public LiveData<List<AccountRecord>> getAcountRecordByType(String type) {
        return accountRecordRepository.getAcountRecordByType(type);
    }

4、清空所有账单的设置（“简陋版”）

@Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {

        switch (item.getItemId()){
            case R.id.clear:
                AlertDialog.Builder builder = new AlertDialog.Builder(requireActivity());
                builder.setTitle("清空账单");
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        accountRecordViewModel.deleteAllAccountRecord();
                    }
                });
                builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {

                    }
                });
                builder.create();
                builder.show();
                break;
        }
        return super.onOptionsItemSelected(item);
    }

5、滑动删除

new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0,ItemTouchHelper.START | ItemTouchHelper.END) {
            @Override
            public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
                return false;
            }

            @Override
            public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
                AccountRecord accountRecord = allAccountRecord.get(viewHolder.getLayoutPosition());
                accountRecordViewModel.deleteAccountRecord(accountRecord);
            }
        }).attachToRecyclerView(recyclerView);

三、运行测试