尽管有 framepostion，Motion Layout 的 KeyAttribute 会立即触发

Question

我的转变：

<Transition
    app:constraintSetEnd="@+id/end"
    app:constraintSetStart="@+id/start"
    app:motionInterpolator="linear">

    <KeyFrameSet>
        <KeyAttribute
            app:framePosition="80"
            app:motionTarget="@id/toolbar">
            <CustomAttribute
                app:attributeName="visibility"
                app:customIntegerValue="8" />
        </KeyAttribute>
        <KeyAttribute
            app:framePosition="80"
            app:motionTarget="@id/navHostFragment">
            <CustomAttribute
                app:attributeName="visibility"
                app:customIntegerValue="8" />
        </KeyAttribute>
        <KeyAttribute
            app:framePosition="80"
            app:motionTarget="@id/playerStatus">
            <CustomAttribute
                app:attributeName="visibility"
                app:customIntegerValue="8" />
        </KeyAttribute>
    </KeyFrameSet>

    <OnSwipe
        app:dragDirection="dragUp"
        app:touchRegionId="@id/mlView" />

</Transition>

无论我在 frameposition 中使用什么数字，keyattribute 的可见性都会在动画开始时立即应用。为什么？

Answer 1

将 framePosition="0" 的 <KeyAttribute> 添加到布局的默认值。由于没有关于您的基本值的信息，可能是这样的：

<KeyFrameSet>
    <KeyAttribute
        app:framePosition="0"
        app:motionTarget="@id/toolbar">
        <CustomAttribute
            app:attributeName="visibility"
            app:customIntegerValue="0" />
    </KeyAttribute>
    <KeyAttribute
        app:framePosition="0"
        app:motionTarget="@id/navHostFragment">
        <CustomAttribute
            app:attributeName="visibility"
            app:customIntegerValue="0" />
    </KeyAttribute>
    <KeyAttribute
        app:framePosition="0"
        app:motionTarget="@id/playerStatus">
        <CustomAttribute
            app:attributeName="visibility"
            app:customIntegerValue="0" />
    </KeyAttribute>
</KeyFrameSet>

这将使目标 View 保持可见直到第 79 帧，之后在过渡的第 80 帧它们将消失。

尽管有 framepostion，Motion Layout 的 KeyAttribute 会立即触发

Motion Layout's KeyAttribute triggers immediately despite framepostion

java

android

kotlin

android-motionlayout