在运行时用事件textchanged禁用/启用applicationbar按钮(Windows Phone)。[英] Disable/Enable applicationbar Button in runtime with event textchanged (Windows Phone)

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问题描述

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在代码的这一部分中是事件文本划分以启用te Applicationbar中的按钮.

c#:

private void Textbox_TextChanged(object sender, EventArgs e)
{
    ApplicationBarIconButton btn_guardar = ApplicationBar.Buttons[0] as applicationBarIconButton;

    if (!string.IsNullOrEmpty(txt_nom_usuario.Text) && !string.IsNullOrEmpty(txt_edad_usuario.Text) && !string.IsNullOrEmpty(txt_peso_usuario.Text))
    {
        btn_guardar.IsEnabled = true;
    }
    else
        btn_guardar.IsEnabled = false; 
}

xaml:

<phone:PhoneApplicationPage.ApplicationBar>
    <shell:ApplicationBar Mode="Default" IsVisible="True">
        <shell:ApplicationBarIconButton x:Name="btn_guardar" IconUri="/icons/appbar.save.rest.png" Text="Guardar" Click="btn_guardar_Click" IsEnabled="False" />
        <shell:ApplicationBarIconButton x:Name="btn_atras" IconUri="/icons/appbar.back.rest.png" Text="Atrás" Click="btn_atras_Click" />
    </shell:ApplicationBar>
</phone:PhoneApplicationPage.ApplicationBar>

<TextBlock x:Name="lbl_ingresanombre" Height="39" Margin="60,28,0,0" TextWrapping="Wrap" HorizontalAlignment="Left" VerticalAlignment="Top" Width="248" FontSize="29.333" FontFamily="{StaticResource Helvetica}"><Run Text="Ingresa "/><Run Text="tu nombre"/></TextBlock>
<TextBox x:Name="txt_nom_usuario" Height="63" Margin="47,58,69,0" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" VerticalAlignment="Top" IsEnabled="True" />

<TextBlock x:Name="lbl_edad" Height="38" Margin="60,117,0,0" TextWrapping="Wrap" Text="Ingresa tu edad" VerticalAlignment="Top" FontSize="29.333" HorizontalAlignment="Left" FontFamily="{StaticResource Helvetica}"/>
<TextBox x:Name="txt_edad_usuario" InputScope="TelephoneLocalNumber" Height="63" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" Margin="47,147,69,0" VerticalAlignment="Top" MaxLength="3" />

<TextBlock x:Name="lbl_peso" Height="42" Margin="60,0,0,178" TextWrapping="Wrap" Text="Peso" HorizontalAlignment="Left" VerticalAlignment="Bottom" Width="74" FontSize="29.333" d:LayoutOverrides="HorizontalAlignment" FontFamily="{StaticResource Helvetica}"/>
<TextBox x:Name="txt_peso_usuario" InputScope="TelephoneLocalNumber" Margin="47,0,69,125" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" Height="63" VerticalAlignment="Bottom"/>

推荐答案

应用程序栏在XAML中设置时不支持某些基本功能.您必须通过代码创建条和按钮和/或菜单项.

这是一个示例,如何创建栏并向其添加控件.然后可以从代码中访问控件:

//button
var appBarButton = new ApplicationBarIconButton
{
    IconUri = new Uri("/Images/YourImage.png", UriKind.Relative),
    Text = "click me"
};
appBarButton.Click += new EventHandler(appBarButton_Click);

//menu item
ApplicationBarMenuItem appBarMenuItem = new ApplicationBarMenuItem
{
    Text = "a menu item"
}
appBarMenuItem.Click += new EventHandler(appBarMenuItem_Click);

//application bar

//Note that this is not a variable declaration
//'ApplicationBar' is a property of 'PhoneApplicationPage'

ApplicationBar = new ApplicationBar();
ApplicationBar.Buttons.Add(appBarButton);
ApplicationBar.MenuItems.Add(appBarMenuItem);

//the events
private void appBarButton_Click(object sender, EventArgs e)
{
}

private void appBarMenuItem_Click(object sender, EventArgs e)
{
}

完成所有操作后,您已经通过代码创建了自己的ApplicationBar.现在您可以从代码更改属性,例如:

var theButton = (ApplicationBarIconButton)ApplicationBar.Buttons[0];

if(someCondition)
{
    theButton.IsEnabled = true;
}
else
{
    theButton.IsEnabled = false;
}

//or shorter:
theButton.IsEnabled = someCondition

这只是一个例子.在经文本变化的事件中,您还可以访问应用程序栏控件.在这些事件中,您可以将上述代码放置以更改应用程序barbutton.希望这能为您清除一切!更多阅读和信息:

本文地址:https://www.itbaoku.cn/post/2352692.html

问题描述

In this part of the code is the event TextChanged to enable the button in te applicationbar.

C#:

private void Textbox_TextChanged(object sender, EventArgs e)
{
    ApplicationBarIconButton btn_guardar = ApplicationBar.Buttons[0] as applicationBarIconButton;

    if (!string.IsNullOrEmpty(txt_nom_usuario.Text) && !string.IsNullOrEmpty(txt_edad_usuario.Text) && !string.IsNullOrEmpty(txt_peso_usuario.Text))
    {
        btn_guardar.IsEnabled = true;
    }
    else
        btn_guardar.IsEnabled = false; 
}

XAML:

<phone:PhoneApplicationPage.ApplicationBar>
    <shell:ApplicationBar Mode="Default" IsVisible="True">
        <shell:ApplicationBarIconButton x:Name="btn_guardar" IconUri="/icons/appbar.save.rest.png" Text="Guardar" Click="btn_guardar_Click" IsEnabled="False" />
        <shell:ApplicationBarIconButton x:Name="btn_atras" IconUri="/icons/appbar.back.rest.png" Text="Atrás" Click="btn_atras_Click" />
    </shell:ApplicationBar>
</phone:PhoneApplicationPage.ApplicationBar>

<TextBlock x:Name="lbl_ingresanombre" Height="39" Margin="60,28,0,0" TextWrapping="Wrap" HorizontalAlignment="Left" VerticalAlignment="Top" Width="248" FontSize="29.333" FontFamily="{StaticResource Helvetica}"><Run Text="Ingresa "/><Run Text="tu nombre"/></TextBlock>
<TextBox x:Name="txt_nom_usuario" Height="63" Margin="47,58,69,0" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" VerticalAlignment="Top" IsEnabled="True" />

<TextBlock x:Name="lbl_edad" Height="38" Margin="60,117,0,0" TextWrapping="Wrap" Text="Ingresa tu edad" VerticalAlignment="Top" FontSize="29.333" HorizontalAlignment="Left" FontFamily="{StaticResource Helvetica}"/>
<TextBox x:Name="txt_edad_usuario" InputScope="TelephoneLocalNumber" Height="63" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" Margin="47,147,69,0" VerticalAlignment="Top" MaxLength="3" />

<TextBlock x:Name="lbl_peso" Height="42" Margin="60,0,0,178" TextWrapping="Wrap" Text="Peso" HorizontalAlignment="Left" VerticalAlignment="Bottom" Width="74" FontSize="29.333" d:LayoutOverrides="HorizontalAlignment" FontFamily="{StaticResource Helvetica}"/>
<TextBox x:Name="txt_peso_usuario" InputScope="TelephoneLocalNumber" Margin="47,0,69,125" TextWrapping="Wrap" Text="&#xa;" FontSize="21.333" Height="63" VerticalAlignment="Bottom"/>

推荐答案

The application bar doesn't support some basic features when it is set in XAML. You'll have to create the bar and buttons and/or menu items through code.

Here's an example how you can create the bar and add controls to it. The controls can then be accessed later from code:

//button
var appBarButton = new ApplicationBarIconButton
{
    IconUri = new Uri("/Images/YourImage.png", UriKind.Relative),
    Text = "click me"
};
appBarButton.Click += new EventHandler(appBarButton_Click);

//menu item
ApplicationBarMenuItem appBarMenuItem = new ApplicationBarMenuItem
{
    Text = "a menu item"
}
appBarMenuItem.Click += new EventHandler(appBarMenuItem_Click);

//application bar

//Note that this is not a variable declaration
//'ApplicationBar' is a property of 'PhoneApplicationPage'

ApplicationBar = new ApplicationBar();
ApplicationBar.Buttons.Add(appBarButton);
ApplicationBar.MenuItems.Add(appBarMenuItem);

//the events
private void appBarButton_Click(object sender, EventArgs e)
{
}

private void appBarMenuItem_Click(object sender, EventArgs e)
{
}

When all this is done, you've created your own ApplicationBar through code. Now you can change the properties from code, like this:

var theButton = (ApplicationBarIconButton)ApplicationBar.Buttons[0];

if(someCondition)
{
    theButton.IsEnabled = true;
}
else
{
    theButton.IsEnabled = false;
}

//or shorter:
theButton.IsEnabled = someCondition

This is just an example. In the TextChanged events you can also access the ApplicationBar controls. In these events you can place above code to change the ApplicationBarButton. Hope this clears things up for you! More reading and info: