Question

我有这个XAML代码：

       <Button x:Name="btnStartRecord" Visibility="Collapsed">
            <Button.BorderBrush>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="Black" Offset="0"/>
                    <GradientStop Color="#FFF3883E" Offset="1"/>
                </LinearGradientBrush>
            </Button.BorderBrush>
        </Button>
        <Button x:Name="btnStopRecord" Visibility="Collapsed">
            <Button.BorderBrush>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="Black" Offset="0"/>
                    <GradientStop Color="#FFF3883E" Offset="1"/>
                </LinearGradientBrush>
            </Button.BorderBrush>
        </Button>

<VisualStateManager.VisualStateGroups>
            <VisualStateGroup x:Name="MainStates">
                <VisualState x:Name="RecordIconState">
                    <Storyboard>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="btnStartRecord" Storyboard.TargetProperty="(UIElement.Visibility)">
                            <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="Visible"/>
                            <!--<DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>-->
                        </ObjectAnimationUsingKeyFrames>
                        <!--<ObjectAnimationUsingKeyFrames Storyboard.TargetName="btnStopRecord" Storyboard.TargetProperty="Visibility">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="Collapsed"/>
                        </ObjectAnimationUsingKeyFrames>-->
                    </Storyboard>
                </VisualState>
                <VisualState x:Name="StopRecordIconState">
                    <Storyboard>
                        <!--<ObjectAnimationUsingKeyFrames Storyboard.TargetName="btnStartRecord" Storyboard.TargetProperty="Visibility">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="Collapsed"/>
                        </ObjectAnimationUsingKeyFrames>-->
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="btnStopRecord" Storyboard.TargetProperty="Visibility">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
                        </ObjectAnimationUsingKeyFrames>
                    </Storyboard>
                </VisualState>
                </VisualStateGroup>                
        </VisualStateManager.VisualStateGroups>

在Code Behind中，我在OnLoad / Constructor中调用了以下函数：

private void SwitchRecordButtonContent()
    {
        {
            if (m_bRecording)
            {
                //btnStartStopRecord.Content = "StopRecord";
                VisualStateManager.GoToState(this, StopRecordIconState.Name, false);
                VisualState currentState = MainStates.CurrentState;
                Visibility temp = btnStartRecord.Visibility;
            }
            else
            {
                //btnStartStopRecord.Content = "StartRecord";
                bool op = VisualStateManager.GoToState((Button)this.btnStartRecord, RecordIconState.Name, false); // I get this always false
                VisualState currentState = MainStates.CurrentState;
                Visibility temp = btnStartRecord.Visibility;
            }
        }
    }

但我看不到视觉状态的变化，我无法弄清楚原因：（

我有什么问题吗？

Answer 1

您正在致电

VisualStateManager.GoToState((Button)this.btnStartRecord, RecordIconState.Name, false); // I get this always false

但基于一瞥，你应该打电话

VisualStateManager.GoToState(this, RecordIconState.Name, false);

Answer 2

作为上述评论中提到的atomaras，将代码移动到usercontrol的根目录它有效：）

VisualStateManager.GoToState返回false并且不更改Visual State

2 个答案: