java 在由查询填充的 jcombobox 中设置默认值
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Setting a default value in a jcombobox populated by a query
提问by SamiSunshine
I am currently writing a program in Java that uses a query populated jcombobox. I was wondering if there is a way to have a default selected value when the program executes. My query is a list of languages listed alphabetically, but I am curious if it is posible to have English (which is in the middle of the list) be the default value.
我目前正在用 Java 编写一个程序，该程序使用一个查询填充的 jcombobox。我想知道是否有办法在程序执行时有一个默认的选定值。我的查询是按字母顺序列出的语言列表，但我很好奇是否可以将英语（位于列表中间）作为默认值。
I know that when you manually hard code the values into the jcombobox you can set the default variable as
我知道当您手动将值硬编码到 jcombobox 中时，您可以将默认变量设置为
jcombobox.setSelectedIndex(int anIndex);
or
或者
jcombobox.setSelectedItem(Object anObject);
but I am unsure when a ResultSet loops and populates the jcombobox.
但我不确定 ResultSet 何时循环并填充 jcombobox。
Currently my code is:
目前我的代码是：
languageLabel =new JLabel("Languages:");
rowFour.add(languageLabel,BorderLayout.WEST);//adding to my current panel
langbox = new JComboBox();
rowFour.add(langbox,BorderLayout.WEST);
try
{
con = DriverManager.getConnection ("jdbc:oracle:thin:@localHost:portNumber:ORCL", "username", "password");
statement = con.createStatement();
}
catch(SQLException sqle)
{
System.out.println(sqle);
}
langbox.removeAllItems();
langbox.addItem("Please Select...");
try
{
ResultSet rs = statement.executeQuery("select language from language order by 1");
while (rs.next())
{
langbox.addItem(rs.getString(1));
//Thinking that this is where a default value would be located
}
}
catch(Exception e)
{
System.err.println(e);
}
Thank you for your time.
感谢您的时间。
采纳答案by Angelo Fuchs
ResultSet rs = statement.executeQuery("select language from language order by 1");
while (rs.next()) {
langbox.addItem(rs.getString(1));
//I'm thinking that this is where a default value would be located
if(rs.getString(1).equals(myDefaultLanguageVariable)) {
langbox.setSelectedItem(rs.getString(1));
}
}
btw: You should clean up that code, its not good that way.
顺便说一句：你应该清理那些代码，那样不好。
