Question

我试图在UWP C ++应用中使用ContentDialog^。使用MessageDialog^ 您可以轻松设置触摸时调用的按钮和命令Windows::UI::Popups::UICommand

MessageDialog^ msg = ref new MessageDialog("Data changed - Save?");
msg->Title = "Warning";

// Add commands and set their callbacks.
UICommand^ continueCommand = ref new UICommand("Yes", ref new UICommandInvokedHandler(this, &MainPage::CommandInvokedHandler));
UICommand^ upgradeCommand = ref new UICommand("No", ref new UICommandInvokedHandler(this, &MainPage::CommandInvokedHandler));
UICommand^ cancelCommand = ref new UICommand("Cancel", ref new UICommandInvokedHandler(this, &MainPage::CommandInvokedHandler));

然后您可以轻松访问

发送给CommandInvokedHandler的值

void MainPage::CommandInvokedHandler(Windows::UI::Popups::IUICommand^ command)
{
    // Display message
    if (command->Label == "Yes") {
        Save();
    } else if (command->Label == "No") {
        Skip();
    } else if (command->Label == "Cancel") {
        //do nothing
    }
}

但是，内容对话框的工作方式完全不同。它是这样创建的

TextBox^ inputTextBox = ref new TextBox();
inputTextBox->AcceptsReturn = false;
inputTextBox->Height = 32;
ContentDialog^ dialog = ref new ContentDialog();

dialog->Content = inputTextBox;
dialog->Title = "Rename";
dialog->IsSecondaryButtonEnabled = true;
dialog->PrimaryButtonText = "Ok";
dialog->SecondaryButtonText = "Cancel";
dialog->ShowAsync();

我要么设置属性dialog->PrimaryButtonCommand，因为某些（未知的奇怪）原因会使用完全不同的Windows::UI::Xaml::Input::ICommand ...
或者我应该使用dialog->PrimaryButtonClick？

我很难在任何地方找到任何C ++示例，而且文档并没有清除任何内容。

Answer 1

您可以在PrimaryButtonCommand中使用PrimaryButtonClick或ContentDialog。点击主按钮时将调用它们。它们之间的区别在于PrimaryButtonClick是event，但PrimaryButtonCommand是类型为ICommand的属性。请注意ICommand与MessageDialog中使用的UICommand不同，它们完全是两回事。

ICommand更多地用于XAML绑定。要使用它，我们将实现ICommand接口，然后在视图模型中使用。有关详细信息，请参阅Executing commands in a view model。

在您的情况下，当您在代码隐藏中创建内容对话框时，我认为您可以使用如下所示的事件处理程序方法订阅PrimaryButtonClick事件：

void MainPage::Button_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
    TextBox^ inputTextBox = ref new TextBox();
    inputTextBox->AcceptsReturn = false;
    inputTextBox->Height = 32;
    ContentDialog^ dialog = ref new ContentDialog();

    dialog->Content = inputTextBox;
    dialog->Title = "Rename";
    dialog->IsSecondaryButtonEnabled = true;
    dialog->PrimaryButtonText = "Ok";
    dialog->SecondaryButtonText = "Cancel";
    dialog->PrimaryButtonClick += ref new Windows::Foundation::TypedEventHandler<Windows::UI::Xaml::Controls::ContentDialog ^, Windows::UI::Xaml::Controls::ContentDialogButtonClickEventArgs ^>(this, &MainPage::OnPrimaryButtonClick);
    dialog->ShowAsync();
}


void MainPage::OnPrimaryButtonClick(Windows::UI::Xaml::Controls::ContentDialog ^sender, Windows::UI::Xaml::Controls::ContentDialogButtonClickEventArgs ^args)
{
    // Do something useful here
}

UWP C ++ ContentDialog PrimaryButtonCommand或PrimaryButtonClick

1 个答案: