小编Bas*_*ant的帖子

我是android的新手,我想使用achartengine来实现时间图表,它代表来自通话记录的每日拨出呼叫持续时间.

有谁知道我该怎么做,我该怎么办？

我有一个问题,需要帮助,Class.forName("com.mysql.jdbc.Driver")当我从eclipse运行webservice时,抛出类没有发现异常,但是当我创建新的java项目时,它运行完美.

我mysql-connector-java-5.1.19-bin.jar在两个项目的构建路径中添加了但我不知道webservice中的问题是什么.

  public String insertOrder(
         int current_id, 
        int table_id) 
        {
            try {
      Class.forName("com.mysql.jdbc.Driver");
      Connection con = 
    DriverManager.getConnection("jdbc:mysql://localhost:3306/myhoteldb", "root", "mypassword");
      PreparedStatement st = 
    con.prepareStatement("insert into orders(orders.current_id,orders.table_id) values(?,?)");
      st.setInt(1, current_id);
      st.setInt(2, table_id);

      st.executeUpdate();
      } catch (Exception e) {
      System.out.println(e.getMessage());
      }
      return "record inserted";
      }
    }

这个错误日志

  java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at pkg.MyServices.insertOrder(MyServices.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.axis2.rpc.receivers.RPCUtil.invokeServiceClass(RPCUtil.java:194)
at org.apache.axis2.rpc.receivers.RPCMessageReceiver.invokeBusinessLogic(RPCMessageReceiver.java:102)
at org.apache.axis2.receivers.AbstractInOutMessageReceiver.invokeBusinessLogic(AbstractInOutMessageReceiver.java:40) …

我的ListView有问题.当我选择它到我自己的自定义drawable时,我想更改所选项目的背景,但它不起作用.

我希望在图像中具有此效果作为选定项目

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true" 
          android:drawable="@drawable/selected_item"/>
    <item android:drawable="@android:color/transparent" />
</selector>

这是list_row的文本

<!-- this layout is used to view row of category list and resturant list  -->
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/txt_category_row" 
    android:gravity="center"
    android:layout_width="match_parent" 
    android:textColor="@color/BLACK"
    android:layout_height="55dp" 
    android:padding="10dp"
    android:text="@string/hello" 
    android:layout_marginTop="5dp"

    android:textAppearance="?android:attr/textAppearanceLarge" />

而这个ListView code.xml:

<ListView android:id="@+id/list_category" 
    android:layout_alignParentLeft="true" 
    android:layout_height="fill_parent" 
    android:layout_width="184dp" 
    android:dividerHeight="2px"
    android:background="@android:color/transparent"
    android:cacheColorHint="@android:color/transparent"
    android:layout_marginTop="5dp"  
    android:listSelector="@drawable/list_selector"
    android:divider="@color/Gray"  >