Question

我仍在尝试理解Java编程并遇到了这个挑战，我有一个表，并希望通过此DefaultTableModel

将数据加载到其中

private Vector <Object> Headings =new Vector <Object>();
private Vector <Object> Data = new Vector <Object> ();
    Headings = acquire.Account("StudentHeader");
    Data = acquire.Account("StudentData");
    Object[] ids = Headings.toArray();
    //Object[][] out = to2DimArray(Data);  


  DefaultTableModel model = new DefaultTableModel(out, ids);

根据需要，“out”是二维数组。问题是我不知道如何将我的“数据”传输/更改为表所需的二维数组。我尝试使用DefaultTableModel的Vector形式，但是有一个错误，所以我决定使用加载标题的数组形式。你能告诉我如何将矢量转换成二维数组，这样我可以加载我的表吗？

Answer 1

逻辑上说，一个矢量是一个可调整大小的一维数组，所以我不认为你可以把它转换成一个二维数组。

我认为您可以扩展DefaultTableModel或创建TableModel class的anonymous class，而不是使用AbstractTableModel class，然后创建自己的表模型然后，您可以使用它来实例化您的表。

检查TableDemo.java

.....

class MyTableModel extends AbstractTableModel {
    private String[] columnNames = {"First Name",
                                    "Last Name",
                                    "Sport",
                                    "# of Years",
                                    "Vegetarian"};
    private Object[][] data = {
    {"Kathy", "Smith",
     "Snowboarding", new Integer(5), new Boolean(false)},
    {"John", "Doe",
     "Rowing", new Integer(3), new Boolean(true)},
    {"Sue", "Black",
     "Knitting", new Integer(2), new Boolean(false)},
    {"Jane", "White",
     "Speed reading", new Integer(20), new Boolean(true)},
    {"Joe", "Brown",
     "Pool", new Integer(10), new Boolean(false)}
    };

    public int getColumnCount() {
        return columnNames.length;
    }

    public int getRowCount() {
        return data.length;
    }

    public String getColumnName(int col) {
        return columnNames[col];
    }

    public Object getValueAt(int row, int col) {
        return data[row][col];
    }

    /*
     * JTable uses this method to determine the default renderer/
     * editor for each cell.  If we didn't implement this method,
     * then the last column would contain text ("true"/"false"),
     * rather than a check box.
     */
    public Class getColumnClass(int c) {
        return getValueAt(0, c).getClass();
    }

...

它很好地解释了这个实现。

Answer 2

您的Data对象是一维的Vector，因此您无法将其直接转换为二维对象。尝试将数据构建为Vector<Vector<Object>>，其中每个元素都是表格的一行。

这样的事情：

Vector <Object> headings = new Vector <Object>();       
Vector <Vector<Object>> data = new Vector <Vector<Object>> ();

headings = acquire.Account("StudentHeader");   

for(int i = 0 ; i < yourStudentDataNumber ; i++) {
    Vector <Object> dataElement = new Vector <Object>();
    dataElement = acquire.Account("StudentHeader"); 
    //i don't know what is acquire object, this for loop is only an example
    // however you need to build a Vector<Object> for each row of the table

    data.add(dataElement);
}       

Object[] ids = headings.toArray();

int numberOfRow = data.size();     

Object[][] bidimArray = new Object[numberOfRow][];      

for(int i = 0 ; i < numberOfRow ; i++) {
    bidimArray[i] = data.get(i).toArray();
}

DefaultTableModel model = new DefaultTableModel(bidimArray, ids);

Answer 3

好吧，这就是我为此做出的努力，它起作用了：

Vector <Object> Headings =new Vector <Object>();
Vector <Object> Data = new Vector <Object> ();
Vector <Object> Extract = new Vector <Object> ();
Headings = acquire.Account("IncomeHeader");
Data = acquire.Account("IncomeData");

int DataSize = Data.size(); int colum = Headings.size();
    int round = DataSize/colum; int cover = DataSize; int t =1;
    while(t<=round){
        Extract = getVector(Data, colum);
    model.addRow(Extract); 
    t++;
    }

private Vector<Object> getVector(Vector<Object> data, int colum) {
      Vector vector = new Vector(); int h = data.size(); int r = 0;
    while(h>s){
        r++; 
        vector.add(data.get(s));
        s++;
    if(r==colum){
        System.out.println("vector: "+vector);
        return vector;
    }
    }
    return null;
}

从给定的Object Vector创建二维数组

3 个答案: