我是 SWT 的新手，目前正在努力使Label实例可见。目前，我需要手动调整窗口大小以使其显示。我在 SO 上发现了一个类似的问题，提到了 SWT 的缓存。所以我尝试了建议的调用，shell.layout();但它对我不起作用。这是我的代码：
public class SimpleTextEditorCount {
private Display display = new Display();
private Shell shell = new Shell(this.display);
private StyledText styledText;
private boolean unsaved;
private File file;
private String lastDirectory;
private Label status;
public SimpleTextEditorCount() {
this.shell.setLayout(new GridLayout());
this.createMenuBar();
this.styledText = new StyledText(this.shell, SWT.MULTI | SWT.WRAP
| SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL);
this.styledText.setLayoutData(new GridData(GridData.FILL_BOTH));
final Font font = new Font(this.shell.getDisplay(), "Book Antiqua", 12,
SWT.NORMAL);
this.styledText.setFont(font);
this.styledText.addModifyListener(new ModifyListener() {
@Override
public void modifyText(ModifyEvent e) {
unsaved = true;
}
});
this.shell.setText("Editor");
this.shell.setSize(400, 300);
this.createCount();
this.shell.open();
while (!this.shell.isDisposed()) {
if (!this.display.readAndDispatch()) {
this.display.sleep();
}
}
this.display.dispose();
}
private void createMenuBar() {
// Create the File top-level menu
Menu menu = new Menu(this.shell, SWT.BAR);
MenuItem open = new MenuItem(menu, SWT.CASCADE);
open.setText("File");
Menu dropMenu = new Menu(this.shell, SWT.DROP_DOWN);
open.setMenu(dropMenu);
// File->Open
open = new MenuItem(dropMenu, SWT.NULL);
open.setText("Open...\tCtrl+O");
open.setAccelerator(SWT.CTRL + 'O');
open.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
loadText();
}
});
// File->Save
MenuItem save = new MenuItem(dropMenu, SWT.NULL);
save.setText("Save\tCtrl+S");
save.setAccelerator(SWT.CTRL + 'S');
save.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
saveText();
}
});
// File->Save As
MenuItem saveAs = new MenuItem(dropMenu, SWT.NULL);
saveAs.setText("Save As...");
saveAs.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
System.err.println("NEEDS TO BE IMPLEMENTED");
}
});
// File->Exit
MenuItem exit = new MenuItem(dropMenu, SWT.SEPARATOR);
exit = new MenuItem(dropMenu, SWT.NULL);
exit.setText("Exit\tAlt+F4");
exit.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
if (saveChanges()) {
shell.dispose();
}
}
});
// Create Edit
MenuItem edit = new MenuItem(menu, SWT.CASCADE);
edit.setText("Edit");
dropMenu = new Menu(shell, SWT.DROP_DOWN);
edit.setMenu(dropMenu); // Create Edit->Cut
edit = new MenuItem(dropMenu, SWT.NULL);
edit.setText("Cut\tCtrl+X");
edit.setAccelerator(SWT.CTRL + 'X');
edit.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
styledText.cut();
}
});
// Create Edit->Copy
MenuItem copy = new MenuItem(dropMenu, SWT.NULL);
copy.setText("Copy\tCtrl+C");
copy.setAccelerator(SWT.CTRL + 'C');
copy.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
styledText.copy();
}
});
// Create Edit->Paste
MenuItem paste = new MenuItem(dropMenu, SWT.NULL);
paste.setText("Paste\tCtrl+V");
paste.setAccelerator(SWT.CTRL + 'V');
paste.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
styledText.paste();
}
});
// Create Select All
MenuItem selectAll = new MenuItem(dropMenu, SWT.SEPARATOR);
selectAll = new MenuItem(dropMenu, SWT.NULL);
selectAll.setText("Select All\tCtrl+A");
selectAll.setAccelerator(SWT.CTRL + 'A');
selectAll.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
System.err.println("NEEDS TO BE IMPLEMENTED");
}
});
MenuItem undo = new MenuItem(dropMenu, SWT.SEPARATOR); // Create Undo
undo = new MenuItem(dropMenu, SWT.NULL);
undo.setText("Undo\tCtrl+Z");
undo.setAccelerator(SWT.CTRL + 'Z');
undo.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
System.err.println("NEEDS TO BE IMPLEMENTED");
}
});
// Create Help
MenuItem help = new MenuItem(menu, SWT.CASCADE);
help.setText("Help");
dropMenu = new Menu(shell, SWT.DROP_DOWN);
help.setMenu(dropMenu); // Create Help->About
help = new MenuItem(dropMenu, SWT.NULL);
help.setText("About");
help.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
System.err.println("NEEDS TO BE IMPLEMENTED");
}
});
this.shell.setMenuBar(menu);
}
public void createCount() {
this.status = new Label(this.shell, SWT.BORDER);
this.status.setText("test");
this.status.setLayoutData(new GridData(GridData.FILL,
GridData.BEGINNING, true, false, 2, 1));
this.shell.layout();
styledText.addModifyListener(new ModifyListener() {
@Override
public void modifyText(ModifyEvent arg0) {
updateStatus();
}
});
styledText.addKeyListener(new KeyListener() {
@Override
public void keyReleased(KeyEvent arg0) {
}
@Override
public void keyPressed(KeyEvent arg0) {
updateStatus();
}
});
}
private void updateStatus() {
StringBuffer buf = new StringBuffer();
buf.append("Offset: ");
buf.append(this.styledText.getCaretOffset());
buf.append("\tChars: ");
buf.append(this.styledText.getCharCount());
buf.append("\tLine: ");
buf.append(this.styledText.getLineAtOffset(this.styledText
.getCaretOffset()) + 1);
buf.append(" of ");
buf.append(this.styledText.getLineCount());
this.status.setText(buf.toString());
}
boolean saveChanges() {
if (!this.unsaved) {
return true;
}
final MessageBox box = new MessageBox(this.shell, SWT.ICON_WARNING
| SWT.YES | SWT.NO | SWT.CANCEL);
box.setMessage("save changes? ");
box.setText("Editor");
final int condition = box.open();
if (condition == SWT.YES) {
return this.saveText();
} else if (condition == SWT.NO) {
return true;
} else {
return false;
}
}
boolean loadText() {
final FileDialog dialog = new FileDialog(this.shell, SWT.OPEN);
if (this.lastDirectory != null) {
dialog.setFilterPath(this.lastDirectory);
}
final String selectedFile = dialog.open();
if (selectedFile == null) {
System.out.println("File is not opened");
return false;
}
this.file = new File(selectedFile);
this.lastDirectory = this.file.getParent();
try {
final BufferedReader reader = new BufferedReader(new FileReader(
this.file));
final StringBuffer buffer = new StringBuffer();
String line = null;
while ((line = reader.readLine()) != null) {
buffer.append(line);
buffer.append("\r\n");
}
this.styledText.setText(buffer.toString());
return true;
} catch (final IOException e) {
}
return false;
}
boolean saveText() {
if (this.file == null) {
final FileDialog fileDialog = new FileDialog(this.shell, SWT.SAVE);
if (this.lastDirectory != null) {
fileDialog.setFilterPath(this.lastDirectory);
}
final String selectedFile = fileDialog.open();
if (selectedFile == null) {
System.out.println("File is not saved");
return false;
}
this.file = new File(selectedFile);
this.lastDirectory = this.file.getParent();
}
try {
final FileWriter writer = new FileWriter(this.file);
writer.write(this.styledText.getText());
writer.close();
this.unsaved = false;
return true;
} catch (final IOException e) {
}
return false;
}
public static void main(String[] args) {
new SimpleTextEditorCount();
}
}
你有什么建议吗？谢谢！
编辑：我用整个文件替换了代码片段。我发现奇怪的行为似乎是由菜单栏触发的。如果我在构造函数中注释掉this.createMenuBar();创建，标签将被正确可视化（由createCount()方法创建）。
编辑：我无法找到正确的解决方案。所以我pack()在打开窗口后添加了一个调用来强制调整大小。以下是我对构造函数所做的更改：
//... code
this.shell.setSize(400, 300);
this.shell.open();
this.shell.pack();
this.shell.setSize(400, 300);
while (!this.shell.isDisposed()) {
if (!this.display.readAndDispatch()) {
this.display.sleep();
}
}
// ... further code
我在没有添加包和调整大小调用的情况下制作了屏幕截图。
并添加了两行：
谢谢！