java 如何从android中的sql server db检索数据
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How to retrieve data from sql server db in android
提问by Reshma
this is the first time I am developing an android application. I want to bind some data with grid view or list view based employee id provided on the text box. How can I do that. Please help me to find a proper solution. Thank you.
这是我第一次开发安卓应用程序。我想将一些数据与文本框中提供的基于网格视图或列表视图的员工 ID 绑定。我怎样才能做到这一点。请帮助我找到合适的解决方案。谢谢你。
ConnectionClass.java:
连接类.java：
import android.annotation.SuppressLint;
import android.os.StrictMode;
import android.util.Log;
import java.sql.SQLException;
import java.sql.Connection;
import java.sql.DriverManager;
/**
* Created by H-PC on 16-Oct-15.
*/
public class ConnectionClass {
String ip = "******";
String classs = "net.sourceforge.jtds.jdbc.Driver";
String db = "IDB";
String un = "sa";
String password = "admin123";
@SuppressLint("NewApi")
public Connection CONN() {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
.permitAll().build();
StrictMode.setThreadPolicy(policy);
Connection conn = null;
String ConnURL = null;
try {
Class.forName(classs);
ConnURL = "jdbc:jtds:sqlserver://" + ip + ";"
+ "databaseName=" + db + ";user=" + un + ";password="
+ password + ";";
conn = DriverManager.getConnection(ConnURL);
} catch (SQLException se) {
Log.e("ERRO", se.getMessage());
} catch (ClassNotFoundException e) {
Log.e("ERRO", e.getMessage());
} catch (Exception e) {
Log.e("ERRO", e.getMessage());
}
return conn;
}
}
-------------------------------------------------------------------------------
MainActivity.java:
主活动.java：
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.view.View.OnClickListener;
import java.sql.Connection;
public class MainActivity extends AppCompatActivity {
Button button1;
TextView txtView1;
EditText editText1;
ConnectionClass connectionClass;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
connectionClass = new ConnectionClass();
button1=(Button)findViewById(R.id.btnSearch);
txtView1=(TextView)findViewById(R.id.searchLbl);
editText1=(EditText)findViewById(R.id.txtSearch);
button1.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
String newValue = editText1.getText().toString().trim();
if (newValue.toString().trim().equals("")) {
txtView1.setText("Please Enter ID");
}
else
{
Connection con = connectionClass.CONN();
if(con==null)
{
String msg="Error in SQL Connection";
}
else
{
String query= "Select * From Employees Where EmpId='"+newValue+"'";
}
}
}
});
}
}
---------------------------------------------------------------------------
Text
文本
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.example.laptop37.myapplication2.MainActivity">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
<EditText
android:layout_width="285dp"
android:layout_height="42dp"
android:id="@+id/txtSearch"
android:layout_weight="1"
android:textColor="@color/material_deep_teal_500"
android:hint="enter id"
android:layout_gravity="center_vertical"
android:layout_below="@+id/textHeading"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="30px"
android:background="#b1e1b1"
android:layout_marginLeft="10px"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Employee Data"
android:id="@+id/textHeading"
android:layout_weight="1"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="30px"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:textAlignment="center"
android:textColor="#2eb114"
android:textSize="70px"
/>
<Button
android:layout_width="85dp"
android:layout_height="42dp"
android:text="Search"
android:id="@+id/btnSearch"
android:layout_weight="0.43"
android:background="@color/background_material_dark"
android:textColor="#ffffff"
android:layout_gravity="center_vertical"
android:layout_alignBottom="@+id/txtSearch"
android:layout_toRightOf="@+id/txtSearch"
android:layout_toEndOf="@+id/txtSearch"
android:layout_marginLeft="10px"
android:layout_marginStart="10px"
android:layout_marginRight="10px"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/searchLbl"
android:layout_below="@+id/txtSearch"
android:layout_alignLeft="@+id/txtSearch"
android:layout_alignStart="@+id/txtSearch"
android:layout_marginTop="64dp" />
<GridView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/gridViewEmp"
android:layout_alignRight="@+id/txtSearch"
android:layout_alignEnd="@+id/txtSearch"
android:layout_below="@+id/txtSearch" />
</RelativeLayout>
</RelativeLayout>
</android.support.design.widget.CoordinatorLayout>
-------------------------------------------------------------------------------
Table(Employees) :
表（员工）：
EmpId EmpName Designation Gender Age Mob Address
----- ------- ----------- ------ --- --- -------
1 asd ttt M 30 fghfhfh
2 dfg yyy F 26 fhgfhfhf
3 dfhh ppp M 47 fghhfghf
--------------------------------------------------------------------------------
Design:
设计：
回答by Punit Sharma
Export the database to the Assetsfolder in App, then fetch details through it.
将数据库导出到AssetsApp中的文件夹，然后通过它获取详细信息。
回答by Tanim reja
You cant access sql server directly ...
你不能直接访问sql server ...
First you need to make a web service because your database sits on your host not on your phone memory card , web service process a request from app and responds accordingly.That is, you pass some SQL query parameters from app to the web service and let your web service handle the request. This web service can be of any type JAVA, PHP, etc. You just need to use standard HTTP methods. click
首先，您需要创建一个 Web 服务，因为您的数据库位于您的主机上而不是您的手机存储卡上，Web 服务处理来自应用程序的请求并做出相应的响应。也就是说，您将一些 SQL 查询参数从应用程序传递给 Web 服务，然后让您的网络服务处理请求。该 Web 服务可以是任何类型的 JAVA、PHP 等。您只需要使用标准的 HTTP 方法。点击
回答by Kristo
Here is an example of how you can display data gathered from a database in to a listview.
下面是一个示例，说明如何将从数据库收集的数据显示到列表视图中。
final ListView listView = getListView();
final String[][] _customerData = MySQL.Get("SELECT Id,Name,Surname FROM customers");
final List<Integer> _currentCustomerIDs = new ArrayList<>();
final List<String> _nameList = new ArrayList<>();
for (String[] customer : _customerData)
{
_currentCustomerIDs.add(Integer.valueOf(customer[0]));
_nameList.add(customer[2] + " " + customer[1]);
}
listView.invalidateViews();
listView.setTextFilterEnabled(true);
listView.setAdapter(getListAdapter());
setListAdapter(new ArrayAdapter<>(this, R.layout.customer_list, _nameList.toArray()));
You need to make a select query, then declare a list of integers, iterate through that list, add it to your arraylist, and finally add it to your listview.
您需要进行选择查询，然后声明一个整数列表，遍历该列表，将其添加到您的数组列表中，最后将其添加到您的列表视图中。
Above is an example adding integers as well as strings to your list with data gathered from a jdbc database.
以上是使用从 jdbc 数据库收集的数据向列表中添加整数和字符串的示例。
Good luck, Hope it helps!
祝你好运，希望有帮助！
回答by Hassan Badawi
in that case you
在那种情况下你
button1.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
String newValue = editText1.getText().toString().trim();
if (newValue.toString().trim().equals("")) {
txtView1.setText("Please Enter ID");
}
else
{
Connection con = connectionClass.CONN();
if(con==null)
{
String msg="Error in SQL Connection";
}
else
{
try {
st = con.createStatement();
// set the result in result set then fetch it
rs = st.executeQuery("Select * From Employees Where EmpId='"+newValue+"'");
if (rs.next()){
Toast.makeText(getApplicationContext()," EmpId :. " + rs.getString("EmpId")+" EmpName :. "+rs.getString("EmpName")+ " Designation :. " + rs.getString("Designation")+" Gender :. "+rs.getString("Gender")+" etc..",LENGTH_LONG).show();
}else{
// you have no record
}
}
}
}
});
});
