Question

我创建了nstextfield的子类，并且我覆盖了keydown事件但是我的代码不起作用，然后我覆盖de keyup事件并且代码完美地工作。我的keydown代码（不起作用）：

-(void)keyDown:(NSEvent *)event {
    NSLog(@"Key released: %hi", [event keyCode]);

    if ([event keyCode]==125){

        [[self window] selectKeyViewFollowingView:self];
    }
    if ([event keyCode]==126){

        [[self window] selectKeyViewPrecedingView:self];
    }

}

我的密钥代码（可行）：

-(void)keyUp:(NSEvent*)event
{if ([event keyCode]==125){

        [[self window] selectKeyViewFollowingView:self];
    }
    if ([event keyCode]==126){

        [[self window] selectKeyViewPrecedingView:self];
    }

    if ([event keyCode]==36){

        [[self window] selectKeyViewFollowingView:self];
    }

    }

我没看到我的keydown代码出现问题。任何建议都将被接受

编辑：我已经读过你必须继承NSTextView而不是NSTextField。

Answer 1

您可以在不使用NSTextFieldDelegate方法进行子类化的情况下完成此操作：

正如@Darren Inksetter所说，你可以使用control:textView:doCommandBySelector:

首先，在接口标记中声明NSTextFieldDelegate。然后实现方法：

- (BOOL)control:(NSControl *)control textView:(NSTextView *)textView doCommandBySelector:(SEL)commandSelector
{
    if( commandSelector == @selector(moveUp:) ){
        // Do yourthing here, like selectKeyViewFollowingView
        return YES;    // Return YES means don't pass it along responders chain. Return NO if you still want system's action on this key.
    }
    if( commandSelector == @selector(moveDown:) ){
        // Do the same with the keys you want to track
        return YES;
    }
    return NO;
}

Answer 2

无法在NSTextField中覆盖keydown事件，如果需要，可以覆盖超级视图的keydown事件，或者可以使用NSTextView或只是覆盖NSTextField中的keyup事件

Answer 3

您需要查看

control:textView:doCommandBySelector:

http://developer.apple.com/library/mac/#documentation/cocoa/reference/NSControlTextEditingDelegate_Protocol/Reference/Reference.html

Answer 4

迅速5示例。


    func control(_ control: NSControl, textView: NSTextView, doCommandBy commandSelector: Selector) -> Bool {
        switch commandSelector {
        case #selector(moveUp(_:)):
            impl.tableView.doCommand(by: commandSelector)
            return true
        case #selector(moveDown(_:)):
            impl.tableView.doCommand(by: commandSelector)
            return true
        default: return false
        }
    }

在NSTextfield中覆盖keydownevent

4 个答案: