在插入对象的SQLite数据库空例外 [英] Null exception on inserting object to SQLite DB

问题描述

林创建一个包含2的EditText领域一个非常基本的片段和一个提交按钮。
在提交的值应该被插入一个一行到我的SQLite数据库。结果
即时得到一个NullPointerException异常，我只是不明白..

在我的片段IM的onCreateView方法让我的字段值，并建立一个点击监听，是这样的：

 查看rootView = inflater.inflate（R.layout.fragment_add_customer，集装箱，FALSE）;
    客户名称=（EditText上）rootView.findViewById（R.id.editCompanyName）;
    customerAddress =（EditText上）rootView.findViewById（R.id.editCompanyAddress）;
    Add按钮=（按钮）rootView.findViewById（R.id.submitCustomerBtn）;
    addButton.setOnClickListener（新View.OnClickListener（）{
        @覆盖
        公共无效的onClick（查看视图）{
            字符串sCustomerName = customerName.getText（）的toString（）。
            字符串sCustomerAddress = customerAddress.getText（）的toString（）。
            如果（sCustomerName.trim（）长度（）方式＆gt; 0＆放大器;＆放大器; sCustomerAddress.trim（）长度（）方式＆gt; 0）{
                客户客户=新客户（）;
                customer.setName（sCustomerName）;
                customer.setAddress（sCustomerAddress）;
                customer.setLocation（未设置）;
                customer.setImage（无）;
                顾客= dataSource.createCustomer（客户）;
                如果（customer.getId（）！= 0）{
                    Toast.makeText（getActivity（），customer.getName（）+ID为：+ customer.getId（）+被创造！，Toast.LENGTH_LONG）.show（）;
                    Log.i（LOGTAG，客户ID为创建+ customer.getId（））;
                }
            }其他{
                Toast.makeText（getActivity（），请填写所有字段。Toast.LENGTH_LONG）.show（）;
            }
        }
    }）;    返回rootView;
 

在我的DataSource类，其中i CONTROLE我的数据库查询和报表IM调用createCustomer方法，它看起来像这样：

 公共客户createCustomer（客户的客户）{
    ContentValues​​值=新ContentValues​​（）;
    values​​.put（BusinessDBOpenHelper.CUSTOMER_NAME，customer.getName（））;
    values​​.put（BusinessDBOpenHelper.CUSTOMER_ADDRESS，customer.getAddress（））;
    values​​.put（BusinessDBOpenHelper.CUSTOMER_LOCATION，customer.getLocation（））;
    values​​.put（BusinessDBOpenHelper.CUSTOMER_IMAGE，customer.getImage（））;
    长insertid = database.insert（BusinessDBOpenHelper.TABLE_CUSTOMER，空，价值）;
    customer.setId（insertid）;
    回报客户;
}
 

我的客户模型也只是containg长的ID，字符串名称，地址字符串，字符串位置，字符串图像的getter和setter ..结果
空的例外是：

 显示java.lang.NullPointerException：尝试调用虚拟方法org.example.app.model.Customer org.example.app.db.BusinessDataSource.createCustomer（org.example.app在一个空对象引用.model.Customer）
        在org.example.app.AddCustomerFragment $ 1.onClick（Fragment.java:55）
 

解决方案

您

  dataSource.createCustomer（客户）;
 

为空，你必须初始化

 数据源
 

地方

Im creating a very basic fragment containing 2 EditText fields and a submit button. On submit the values should be inserted as a row to my SQLite DB.
Im getting a NullPointerException i just dont get..

Inside my onCreateView method of the fragment im getting my field values and setting up a click listener like this:

View rootView = inflater.inflate(R.layout.fragment_add_customer, container, false);
    customerName = (EditText) rootView.findViewById(R.id.editCompanyName);
    customerAddress = (EditText) rootView.findViewById(R.id.editCompanyAddress);
    addButton = (Button) rootView.findViewById(R.id.submitCustomerBtn);
    addButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            String sCustomerName = customerName.getText().toString();
            String sCustomerAddress = customerAddress.getText().toString();
            if(sCustomerName.trim().length() > 0 && sCustomerAddress.trim().length() > 0) {
                Customer customer = new Customer();
                customer.setName(sCustomerName);
                customer.setAddress(sCustomerAddress);
                customer.setLocation("Not set");
                customer.setImage("None");
                customer = dataSource.createCustomer(customer);
                if(customer.getId() != 0) {
                    Toast.makeText(getActivity(), customer.getName() + " with id: " + customer.getId() + " was created!", Toast.LENGTH_LONG).show();
                    Log.i(LOGTAG, "Customer created with id " + customer.getId());
                }
            }else{
                Toast.makeText(getActivity(), "Please fill all fields.", Toast.LENGTH_LONG).show();
            }
        }
    });

    return rootView;

Inside my dataSource class where i controle my DB query and statement im calling the createCustomer method, which looks like this:

public Customer createCustomer(Customer customer) {
    ContentValues values = new ContentValues();
    values.put(BusinessDBOpenHelper.CUSTOMER_NAME, customer.getName());
    values.put(BusinessDBOpenHelper.CUSTOMER_ADDRESS, customer.getAddress());
    values.put(BusinessDBOpenHelper.CUSTOMER_LOCATION, customer.getLocation());
    values.put(BusinessDBOpenHelper.CUSTOMER_IMAGE, customer.getImage());
    long insertid = database.insert(BusinessDBOpenHelper.TABLE_CUSTOMER, null, values);
    customer.setId(insertid);
    return customer;
}

My Customer model is also just containg long id, String name, String address, String location, String image with getters and setters..
The null exception is:

java.lang.NullPointerException: Attempt to invoke virtual method 'org.example.app.model.Customer org.example.app.db.BusinessDataSource.createCustomer(org.example.app.model.Customer)' on a null object reference
        at org.example.app.AddCustomerFragment$1.onClick(Fragment.java:55)

解决方案

Your

dataSource.createCustomer(customer);

is null, you have to initialize

dataSource 

somewhere

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