我正在尝试使用 FileDialog 创建一个浏览按钮并在 Java SWT 中进行复合。 (复合是因为，我使用 CTabFolder 和 CTabItem。我觉得将组件添加到 CTabItem 复合中就足够了)
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.util.StringTokenizer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.FileDialog;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TabFolder;
import org.eclipse.swt.widgets.TabItem;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Text;
import org.eclipse.swt.custom.CBanner;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.wb.swt.SWTResourceManager;
public class DemoShell extends Shell {
protected Composite composite;
private Text filename;
private Table table;
protected Shell shell;
public static void main(String args[]) {
try {
Display display = Display.getDefault();
DemoShell shell = new DemoShell(display);
shell.open();
shell.layout();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
private static boolean parseFile(Table table, String filename) {
try {
BufferedReader br = new BufferedReader( new FileReader(filename) );
String line = "";
StringTokenizer token = null, subtoken = null;
int tokenNum = 1;
while((line = br.readLine()) != null) {
// lineNum++;
// break comma separated file line by line
token = new StringTokenizer(line, ";");
String sno = null;
while(token.hasMoreTokens()) {
subtoken = new StringTokenizer(token.nextToken().toString(), ",");
sno = "";
sno = Integer.toString(tokenNum);
TableItem item = new TableItem (table, SWT.NONE);
item.setText (0, sno );
item.setText (1, subtoken.nextToken());
item.setText (2, subtoken.nextToken());
item.setText (3, subtoken.nextToken());
item.setText (4, subtoken.nextToken());
item.setText (5, subtoken.nextToken());
tokenNum++;
System.out.println("S.No # " + tokenNum + token.nextToken());
}
tokenNum = 0;
}
br.close();
return true;
} catch(Exception e) {
System.err.println("Parse Error: " + e.getMessage());
return false;
}
}
public void displayFiles(String[] files) {
for (int i = 0; files != null && i < files.length; i++) {
filename.setText(files[i]);
filename.setEditable(false);
}
}
/**
* Create the shell.
* @param display
*/
public DemoShell(Display display) {
super(display, SWT.SHELL_TRIM);
TabFolder tabFolder = new TabFolder(this, SWT.NONE);
tabFolder.setBounds(10, 10, 462, 268);
TabItem re_item = new TabItem(tabFolder, SWT.NONE);
re_item.setText("Road Network");
TabItem ttable_item = new TabItem(tabFolder, SWT.NONE);
ttable_item.setText("Time Table");
createContents_tt(tabFolder, ttable_item );
}
/**
* Create contents of the shell.
*/
protected void createContents_tt(TabFolder tabFolder, TabItem ttable_item) {
setText("SWT Application");
setSize(530, 326);
//Table declaration
table = new Table(shell, SWT.BORDER | SWT.FULL_SELECTION);
table.setBounds(10, 153, 450, 107);
table.setHeaderVisible(true);
table.setLinesVisible(true);
String[] titles = {"S.No", "Route", "Transport #", "Cross Point", "Start Time", "End Time"};
for (int i=0; i<titles.length; i++) {
TableColumn column = new TableColumn (table, SWT.NONE);
column.setText (titles [i]);
}
for (int i=0; i<titles.length; i++) {
table.getColumn (i).pack ();
}
Composite composite = new Composite(tabFolder, SWT.NONE);
composite.setLayout(new FillLayout());
Group group_1 = new Group(shell, SWT.NONE);
group_1.setBounds(10, 10, 450, 127);
filename = new Text(group_1, SWT.BORDER);
filename.setBounds(31, 95, 377, 21);
filename.setBackground(SWTResourceManager.getColor(SWT.COLOR_WHITE));
Group group = new Group(group_1, SWT.NONE);
group.setBounds(81, 46, 245, 43);
Label lblEitherBrowseFor = new Label(group_1, SWT.NONE);
lblEitherBrowseFor.setBounds(10, 19, 430, 21);
lblEitherBrowseFor.setText("Either Browse for a file or Try to upload the time table data through Manual entry");
Button btnManual = new Button(group, SWT.NONE);
btnManual.setBounds(162, 10, 75, 25);
btnManual.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
}
});
btnManual.setText("Manual");
Button btnBrowser = new Button(group, SWT.NONE);
btnBrowser.setBounds(27, 10, 75, 25);
btnBrowser.setText("Browse");
btnBrowser.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
FileDialog dialog = new FileDialog(composite, SWT.NULL);
String path = dialog.open();
if (path != null) {
File file = new File(path);
if (file.isFile())
{
displayFiles(new String[] { file.getAbsolutePath().toString()});
DemoShell.parseFile(table, file.toString());
}
else
displayFiles(file.list());
}
}
});
ttable_item.setControl(composite);
}
@Override
protected void checkSubclass() {
// Disable the check that prevents subclassing of SWT components
}
}
尝试以上述方式添加时出现以下错误。
Exception in thread "main" java.lang.Error: Unresolved compilation problems: The constructor FileDialog(Composite, int) is undefined Cannot refer to a non-final variable composite inside an inner class defined in a different method
我请求建议/帮助来清除错误或以任何其他方式重做。
最佳答案
您正在尝试从您定义的Listener (SelectionAdapter) 中访问composite。用于创建监听器的符号隐式创建一个新类。因此，您实际上是在尝试从内部类访问变量 composite ，只有当 composite 是外部类的 static 字段时才能完成此操作。类或者如果您制作composite final。
所以只需执行以下操作:
final Composite composite = new Composite(tabFolder, SWT.NONE);
它会起作用。
<小时/>此外，正如错误所述，没有采用 Composite 的构造函数。您必须使用 Shell。因此，只需执行以下操作:
FileDialog dialog = new FileDialog(composite.getShell(), SWT.NULL);
但是，这会给您带来另一个异常(exception)，因为您在该行上方的某个位置使用了 shell 字段，该字段为 null。由于您的类是 Shell，因此将所有出现的 shell 替换为 this 即可正常工作。
关于java - 文件对话框和复合，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15019415/