如何访问WPF弹出窗口中的元素？

Question

I want to change the color of a button in a popup based on certain conditions and I want to set some text based on those conditions. I need to do this in the code behind.

I have a popup with several TextBlocks in a StackPanel. The first 3 are bound to details about the course (this is a scheduling app; school project). The last one I want to be empty unless there is a conflict concerning that course. That is, I want to dynamically decide what, if anything, goes in the TextBlock each time the popup is opened.

    <Popup Name="CourseListDetail" Width="Auto" Height="Auto">
            <StackPanel>
                <TextBlock Margin="10,10,10,0">
                    <TextBlock.Text>
                        <MultiBinding StringFormat="{}{0}: {1}">
                            <Binding Path="CourseCode"/>
                            <Binding Path="LongTitle"/>
                        </MultiBinding>
                    </TextBlock.Text>
                </TextBlock>
                <TextBlock Margin="10,0,10,0">
                    <TextBlock.Text>
                        <MultiBinding StringFormat="{}{0} - {1}/{2}">
                            <Binding Path="ProfessorsString"/>
                            <Binding Path="Enrollment"/>
                            <Binding Path="Capacity"/>
                        </MultiBinding>
                    </TextBlock.Text>
                </TextBlock>
                <TextBlock Margin="10,0,10,0" Grid.Row="2" Grid.Column="1" Text="{Binding MeetingsString}" TextWrapping="Wrap"
                           HorizontalAlignment="Center"/>
                <TextBlock TextWrapping="WrapWithOverflow"  MaxWidth="300" Text="{Binding Description}" Margin="10,10,10,10"/>
                <TextBlock Name="ConflictText" Foreground="Red" HorizontalAlignment="Center" Text="{Binding ConflictString}"/>
                <Button Name="Detail_AddCourse" Content="Add To Schedule" Margin="10,10,10,10" Padding="5" Background="LightGreen"
                        Click="AddCourseButton_Click"
                        Style="{StaticResource MyButtonStyle}"/>
            </StackPanel>
        </Border>
    </Popup>

I have a function that opens the popup when you click on a course and that gives the popup the DataContext about the course, but I don't know how to access the TextBlock, or the button immediately below it, through the function. I figured there'd be a child property or something so I could call the button, something like:

CourseListDetail.Detail_AddCourse.Background = "Red";

or

CourseListDetail.Child.Button().Background = "Red";

etc.

Code behind function:

    private void CourseListItem_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        ListViewItem selection = sender as ListViewItem;
        Course course = selection.DataContext as Course;

        CourseListDetail.DataContext = course;
        CourseListDetail.PlacementTarget = selection;
        CourseListDetail.IsOpen = true;
        CourseListDetail.Focus();

        hasConflict conflictType = _schedule.HasConflict(course);
        if (conflictType != hasConflict.NO_CONFLICT) {     //If there is a conflict
            //Change button color to red here

            if (conflictType == hasConflict.COURSE_FULL) { //If the course is full
                //Set TextBlock text to conflict message here
            }
        }
        else { //No conflict
            //Set button color to green
        }
    } 

hasConflict is just an enum

Answer 1

Use x:Name instead of Name. Then you will be able to access the element in the code behind. See In WPF, what are the differences between the x:Name and Name attributes? for an explanation.