DependentLayout简介

DependentLayout意为相对位置布局，与DirectionalLayout相比较有更多的排布方式，每个组件可以指定相对于其他同级组件的位置，也可以指定相对于父组件的位置。可以使用DependentLayout布局来实现更加复杂的UI界面，同时也可以和其他布局相结合组合出需要的UI界面。

常用属性

相对于指定组件的位置属性

<?xml version="1.0" encoding="utf-8"?>
<DependentLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:height="match_parent"
    ohos:width="match_parent"
    ohos:alignment="center">

    <Text
        ohos:id="$+id:text_01"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第一个Text."
        ohos:text_size="50"
        />
    <Text
        ohos:id="$+id:text_02"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第二个Text."
        ohos:text_size="50"
        ohos:above="$id:text_01"
        />

</DependentLayout>
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将ohos:above="$id:text_01" 改为ohos:below="$id:text_01"，效果如下。

将ohos:above="$id:text_01" 改为ohos:left_of="$id:text_01"，效果如下，其他自行验证。

子组件相对于父组件的位置属性

<?xml version="1.0" encoding="utf-8"?>
<DependentLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:height="match_parent"
    ohos:width="match_parent"
    ohos:alignment="center">

    <Text
        ohos:id="$+id:text_01"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第一个Text."
        ohos:text_size="50"
        ohos:align_parent_bottom="true"
        />
    <Text
        ohos:id="$+id:text_02"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第二个Text."
        ohos:text_size="50"
        ohos:align_parent_top="true"
        />
    <Text
        ohos:id="$+id:text_03"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第三个Text."
        ohos:text_size="50"
        ohos:align_parent_right="true"
        />
    <Text
        ohos:id="$+id:text_04"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:background_element="$graphic:background_dependent_layout"
        ohos:text="我是第四个Text."
        ohos:text_size="50"
        ohos:center_in_parent="true"
        />
</DependentLayout>
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示例

<?xml version="1.0" encoding="utf-8"?>
<DependentLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:height="match_parent"
    ohos:width="match_parent">

    <Text
        ohos:id="$+id:text_01"
        ohos:height="70vp"
        ohos:width="match_parent"
        ohos:background_element="#CCCCCC"
        ohos:text="Header"
        ohos:text_alignment="center"
        ohos:text_size="50"
        ohos:align_parent_top="true"
        />
    <Text
        ohos:id="$+id:text_02"
        ohos:height="match_parent"
        ohos:width="100vp"
        ohos:background_element="#5C6E71"
        ohos:text="LEFT"
        ohos:text_alignment="center"
        ohos:text_size="50"
        ohos:align_parent_left="true"
        ohos:below="$id:text_01"
        />
    <Text
        ohos:id="$+id:text_03"
        ohos:height="match_parent"
        ohos:width="100vp"
        ohos:background_element="#5C6E71"
        ohos:text="Right"
        ohos:text_alignment="center"
        ohos:text_size="50"
        ohos:align_parent_right="true"
        ohos:below="$id:text_01"
        />
    <Text
        ohos:id="$+id:text_05"
        ohos:height="match_parent"
        ohos:width="match_parent"
        ohos:background_element="#16CCB7"
        ohos:text_alignment="center"
        ohos:text="Center"
        ohos:text_size="50"
        ohos:right_margin="100vp"
        ohos:below="$id:text_01"
        ohos:right_of="$id:text_02"
        />
    <Text
        ohos:id="$+id:text_04"
        ohos:height="50vp"
        ohos:width="match_parent"
        ohos:background_element="#CCCCCC"
        ohos:text="Footer"
        ohos:text_size="50"
        ohos:align_parent_bottom="true"
        />

</DependentLayout>
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至此，我们已经了解并会使用HarmonyOS Java UI的六大布局，下一节我们将对六大布局进行总结，并将前面没有提到的各类属性做详细的归纳。