本文介绍在鸿蒙应用中TabList和TabList.Tab组件的基本用法。java
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准备TabList页面布局设计模式
在layout目录下建立TabList布局，将其命名为ability_tablist.xml。架构
<?xml version="1.0" encoding="utf-8"?><DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_parent" ohos:width="match_parent" ohos:orientation="vertical"> <TabList ohos:id="$+id:tab_list" ohos:background_element="#FFFF7F" ohos:top_margin="10vp" ohos:tab_margin="24vp" ohos:tab_length="140vp" ohos:text_size="20fp" ohos:height="36vp" ohos:width="match_parent" ohos:layout_alignment="center" ohos:orientation="horizontal" ohos:text_alignment="center" ohos:normal_text_color="#999999" ohos:selected_text_color="#000000" ohos:selected_tab_indicator_color="#000000" ohos:selected_tab_indicator_height="2vp"/> <DirectionalLayout ohos:id="$+id:tab_container" ohos:height="match_parent" ohos:width="match_parent"> </DirectionalLayout></DirectionalLayout>
布局代码中第7行~第22行的用于生成TabList组件，定义了TabList的基本属性；第23行~第27行用于生成Tab页面的容器，目前尚未具体内容，稍后有具体代码生成。ide
准备Image页面工具
Image页面主要包含一个Image文件和简单的文字表示：布局
<?xml version="1.0" encoding="utf-8"?><DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_parent" ohos:width="match_parent" ohos:orientation="vertical"> <Component ohos:height="0vp" ohos:weight="3" ohos:width="match_parent" /> <DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_content" ohos:width="match_content" ohos:layout_alignment="center" ohos:orientation="vertical"> <Image ohos:id="$+id:image" ohos:width="match_content" ohos:height="match_content" ohos:layout_alignment="center" ohos:image_src="$media:DevEco" /> <Component ohos:height="20vp" ohos:width="match_parent" /> <Text ohos:id="$+id:text_helloworld" ohos:height="match_content" ohos:width="match_content" ohos:layout_alignment="horizontal_center" ohos:text="Image Tab" ohos:text_color="#007F00" ohos:text_size="100" /> </DirectionalLayout> <Component ohos:height="0vp" ohos:weight="5" ohos:width="match_parent" /></DirectionalLayout>
准备Video页面学习
Video页面包含一个动画，稍微复杂一些。首先是页面自己：动画
<?xml version="1.0" encoding="utf-8"?><DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_parent" ohos:width="match_parent" ohos:orientation="vertical"> <Component ohos:height="0vp" ohos:weight="3" ohos:width="match_parent" /> <DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_content" ohos:width="match_content" ohos:layout_alignment="center" ohos:orientation="vertical"> <Component ohos:id="$+id:video_area" ohos:height="300vp" ohos:width="300vp" /> <Component ohos:height="20vp" ohos:width="match_parent" /> <Text ohos:id="$+id:text_helloworld" ohos:height="match_content" ohos:width="match_content" ohos:layout_alignment="horizontal_center" ohos:text="Video Tab" ohos:text_color="#0000FF" ohos:text_size="100" /> </DirectionalLayout> <Component ohos:height="0vp" ohos:weight="5" ohos:width="match_parent" /></DirectionalLayout>
这个文件和Image页面区别不大，只是在用Component组件代替了Image组件。而动画的实际内容则是由graphic目录中的animation_element.xml文件决定：ui
<?xml version="1.0" encoding="utf-8"?><animation-list xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:oneshot="false"> <item ohos:element="$media:video01" ohos:duration="100"/> <item ohos:element="$media:video02" ohos:duration="100"/> <item ohos:element="$media:video03" ohos:duration="100"/> <item ohos:element="$media:video04" ohos:duration="100"/> <item ohos:element="$media:video05" ohos:duration="100"/> <item ohos:element="$media:video06" ohos:duration="100"/> <item ohos:element="$media:video07" ohos:duration="100"/> <item ohos:element="$media:video08" ohos:duration="100"/> <item ohos:element="$media:video09" ohos:duration="100"/> <item ohos:element="$media:video10" ohos:duration="100"/> <item ohos:element="$media:video11" ohos:duration="100"/></animation-list>
生成TabList画面
TabList的每一个Tab页面须要由代码生成，具体参见下面的页面类：
package com.example.helloharmony.slice; import com.example.helloharmony.ResourceTable;import ohos.aafwk.ability.AbilitySlice;import ohos.aafwk.content.Intent;import ohos.agp.components.*;import ohos.agp.components.element.FrameAnimationElement; import java.io.Console; public class TablistAbilitySlice extends AbilitySlice { private Component imageContent; private Component videoContent; private FrameAnimationElement frameAnimationElement; @Override public void onStart(Intent intent) { super.onStart(intent); super.setUIContent(ResourceTable.Layout_ability_tablist); TabList tabList = (TabList) findComponentById(ResourceTable.Id_tab_list); tabList.setTabLength(200); // 设置Tab的宽度 tabList.setTabMargin(26); // 设置两个Tab之间的间距 TabList.Tab tab1 = tabList.new Tab(getContext()); tab1.setText("Image"); tabList.addTab(tab1); TabList.Tab tab2 = tabList.new Tab(getContext()); tab2.setText("Video"); tabList.addTab(tab2); AbilitySlice slice = this; tabList.addTabSelectedListener(new TabList.TabSelectedListener() { @Override public void onSelected(TabList.Tab tab) { ComponentContainer container = (ComponentContainer) findComponentById(ResourceTable.Id_tab_container); if(tab.getText().equals("Image")) { imageContent = LayoutScatter.getInstance(slice).parse(ResourceTable.Layout_iamge_tab, null, false); container.addComponent(imageContent); } else { videoContent = LayoutScatter.getInstance(slice).parse(ResourceTable.Layout_video_tab, null, false); frameAnimationElement = new FrameAnimationElement(slice.getContext(), ResourceTable.Graphic_animation_element); Component videoArea = videoContent.findComponentById(ResourceTable.Id_video_area); videoArea.setBackground(frameAnimationElement); frameAnimationElement.start(); container.addComponent(videoContent); } } @Override public void onUnselected(TabList.Tab tab) { if(tab.getText().equals("Video")) { frameAnimationElement.start(); } ComponentContainer container = (ComponentContainer) findComponentById(ResourceTable.Id_tab_container); container.removeAllComponents(); } @Override public void onReselected(TabList.Tab tab) { ComponentContainer container = (ComponentContainer) findComponentById(ResourceTable.Id_tab_container); if(tab.getText().equals("Image")) { container.addComponent(imageContent); } else { frameAnimationElement.start(); container.addComponent(videoContent); } } }); //最开始选选择tab1 tabList.selectTab(tab1); } @Override public void onActive() { super.onActive(); } @Override public void onForeground(Intent intent) { super.onForeground(intent); }}
代码第22行~第27行分别生成了Image和Video两个Tab页。
第29行~第69行是为TabList的各类事件提供响应。须要响应的处理主要有Tab页选择，Tab页取消选择和Tab从新选择。代码中根据当前选中的Tab页面生成或选择不一样的组件。
参考文档
TabList和Tab组件
https://developer.harmonyos.com/cn/docs/documentation/doc-guides/ui-java-component-tablist-tab-0000001062229749
TabList类
https://developer.harmonyos.com/cn/docs/documentation/doc-references/tablist-0000001054238721
Tab List.Tab类
https://developer.harmonyos.com/cn/docs/documentation/doc-references/tablist_tab-0000001054678691
动画开发指导
https://developer.harmonyos.com/cn/docs/documentation/doc-guides/ui-java-animation-0000000000580278
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原文连接：https://developer.huawei.com/consumer/cn/forum/topic/0201551132050440304?fid=0101303901040230869
原做者：面向对象思考