问题
i have another question. I use a ModifyListener for one textfield to activate and deactivate the OK-Button in a swt dialog. It works great.
Now I want to add a ModifyListener for another textfield. I want that the OK-Button only is activated if in both text fields is min one char.
This is the code of the two fields:
descriptionText.addModifyListener(new ModifyListener(){
public void modifyText(ModifyEvent e) {
Text text = (Text) e.widget;
if (text.getText().length() == 0) {
getButton(IDialogConstants.OK_ID).setEnabled(false);
}
if (text.getText().length() >= 1) {
getButton(IDialogConstants.OK_ID).setEnabled(true);
}
}
});
}
the second field:
ccidText.addModifyListener(new ModifyListener(){
public void modifyText(ModifyEvent e) {
Text text = (Text) e.widget;
if (text.getText().length() == 0) {
getButton(IDialogConstants.OK_ID).setEnabled(false);
}
if (text.getText().length() >= 1){
getButton(IDialogConstants.OK_ID).setEnabled(true);
}
}
});
}
I know that it doesn´t work because there are no dependencies between the two buttons. How can i combine it?
I want to set the ok-button false while both modifylistener detect a char. If i delete all chars in one testfield the button must be deactivated again.
Thank u.
回答1:
You can use the same Listener
for both Text
fields and add it for SWT.KeyUp
:
public static void main(String[] args)
{
final Display display = new Display();
Shell shell = new Shell(display);
shell.setText("StackOverflow");
shell.setLayout(new FillLayout(SWT.VERTICAL));
final Text first = new Text(shell, SWT.BORDER);
final Text second = new Text(shell, SWT.BORDER);
final Button button = new Button(shell, SWT.PUSH);
button.setText("disabled");
button.setEnabled(false);
Listener listener = new Listener()
{
@Override
public void handleEvent(Event e)
{
String firstString = first.getText();
String secondString = second.getText();
button.setEnabled(!isEmpty(firstString) && !isEmpty(secondString));
button.setText(button.isEnabled() ? "enabled" : "disabled");
}
};
first.addListener(SWT.KeyUp, listener);
second.addListener(SWT.KeyUp, listener);
shell.pack();
shell.setSize(300, shell.getSize().y);
shell.open();
while (!shell.isDisposed())
{
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}
private static boolean isEmpty(String input)
{
if(input == null)
return true;
else
return input.trim().isEmpty();
}
Looks like this:


The code will basically (on each key stroke) check if both Text
s are empty. If so, disable the Button
, else enable it.
来源:https://stackoverflow.com/questions/22245937/how-to-combine-and-validate-two-text-fields-for-a-swt-dialog