首页新闻找找看学习计划

怎么获取ListBox下的TextBlock的Text属性?

0
悬赏园豆:20 [已解决问题] 解决于 2015-07-15 15:06

代码片段如下:

<StackPanel>
<ListBox Height="440" Width="370" x:Name="wtListBox" Background="White">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" >
<TextBlock Name="pText" Width="70"></TextBlock>     // 1
<TextBlock Name="xText" Width="100"></TextBlock>   // 2
<TextBlock Name="yText" Width="100"></TextBlock>   // 3
<TextBlock Name="zText" Width="100"></TextBlock>   // 4
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>

我想通过页面间值传递给上面4个TextBlock的Text属性赋值,但在OnNavigatedTo()方法中点不出pText,赋值无法进行,用什么方法搞出来。求教。

AkazaAkari的主页 AkazaAkari | 初学一级 | 园豆:184
提问于:2015-07-10 15:31
< >
分享
最佳答案
0

datetemplate里面没办法直接搞出来,你只能借助类似visualtreehelpex等视觉树/逻辑树的相关查找子元素的方法来定位到你的textBlock了

当然还有中简单的方法,就是通过将listitem跟模型双向绑定的方法来解决这个问题,这样你只要通过模型中特定的属性就可以实现对textblock值得操作了

收获园豆:20
visonme | 小虾三级 |园豆:1674 | 2015-07-10 15:50

是这样啊,那能不能用视觉树/逻辑树的方法举个例子,这样的方法没用过,谢谢

AkazaAkari | 园豆:184 (初学一级) | 2015-07-10 16:02

@AkazaAkari: 

这里又有以前写的一个视觉树(父/子)对象查找的辅助类

public static class VisualTreeHelperEx
    {
        public static DependencyObject FindAncestorByType(DependencyObject element, Type type, bool specificTypeOnly)
        {
            if (element == null)
            {
                return null;
            }
            if (specificTypeOnly ? (element.GetType() == type) : (element.GetType() == type || element.GetType().IsSubclassOf(type)))
            {
                return element;
            }
            return VisualTreeHelperEx.FindAncestorByType(VisualTreeHelper.GetParent(element), type, specificTypeOnly);
        }

        public static T FindAncestorByType<T>(DependencyObject depObj) where T : DependencyObject
        {
            if (depObj == null)
            {
                return default(T);
            }
            if (depObj is T)
            {
                return (T)((object)depObj);
            }
            T t = default(T);
            return VisualTreeHelperEx.FindAncestorByType<T>(VisualTreeHelper.GetParent(depObj));
        }

        public static Visual FindDescendantByName(Visual element, string name)
        {
            if (element == null)
            {
                return null;
            }
            if (element is FrameworkElement && (element as FrameworkElement).Name == name)
            {
                return element;
            }
            Visual visual = null;
            if (element is FrameworkElement)
            {
                (element as FrameworkElement).ApplyTemplate();
            }
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++)
            {
                Visual element2 = VisualTreeHelper.GetChild(element, i) as Visual;
                visual = VisualTreeHelperEx.FindDescendantByName(element2, name);
                if (visual != null)
                {
                    break;
                }
            }
            return visual;
        }

        public static Visual FindDescendantByType(Visual element, Type type)
        {
            return VisualTreeHelperEx.FindDescendantByType(element, type, true);
        }

        public static Visual FindDescendantByType(Visual element, Type type, bool specificTypeOnly)
        {
            if (element == null)
            {
                return null;
            }
            if (specificTypeOnly ? (element.GetType() == type) : (element.GetType() == type || element.GetType().IsSubclassOf(type)))
            {
                return element;
            }
            Visual visual = null;
            if (element is FrameworkElement)
            {
                (element as FrameworkElement).ApplyTemplate();
            }
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++)
            {
                Visual element2 = VisualTreeHelper.GetChild(element, i) as Visual;
                visual = VisualTreeHelperEx.FindDescendantByType(element2, type, specificTypeOnly);
                if (visual != null)
                {
                    break;
                }
            }
            return visual;
        }

        public static IEnumerable<Visual> FindAllDescendantByType(Visual element, Type type, bool specificTypeOnly)
        {
            if (element == null)
            {
                return null;
            }
            if (specificTypeOnly ? (element.GetType() == type) : (element.GetType() == type || element.GetType().IsSubclassOf(type)))
            {
                return new List<Visual>
                {
                    element
                };
            }
            List<Visual> list = new List<Visual>();
            if (element is FrameworkElement)
            {
                (element as FrameworkElement).ApplyTemplate();
            }
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++)
            {
                Visual element2 = VisualTreeHelper.GetChild(element, i) as Visual;
                list.AddRange(VisualTreeHelperEx.FindAllDescendantByType(element2, type, specificTypeOnly));
            }
            return list;
        }

        public static IEnumerable<T> FindAllDescendantByType<T>(Visual element) where T : Visual
        {
            IEnumerable<Visual> source = VisualTreeHelperEx.FindAllDescendantByType(element, typeof(T), true);
            return source.Cast<T>();
        }

        public static T FindDescendantByType<T>(Visual element) where T : Visual
        {
            Visual visual = VisualTreeHelperEx.FindDescendantByType(element, typeof(T));
            return (T)((object)visual);
        }

        public static Visual FindDescendantWithPropertyValue(Visual element, DependencyProperty dp, object value)
        {
            if (element == null)
            {
                return null;
            }
            if (element.GetValue(dp).Equals(value))
            {
                return element;
            }
            Visual visual = null;
            if (element is FrameworkElement)
            {
                (element as FrameworkElement).ApplyTemplate();
            }
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++)
            {
                Visual element2 = VisualTreeHelper.GetChild(element, i) as Visual;
                visual = VisualTreeHelperEx.FindDescendantWithPropertyValue(element2, dp, value);
                if (visual != null)
                {
                    break;
                }
            }
            return visual;
        }
    }
visonme | 园豆:1674 (小虾三级) | 2015-07-10 16:11

@visonme: 谢谢,我研究研究

AkazaAkari | 园豆:184 (初学一级) | 2015-07-10 16:14
清除回答草稿
   您需要登录以后才能回答,未注册用户请先注册