1. 长按事件

• 长按事件使用的次数不是很多，但在有些特殊的情况下还是要用到的。
• 比如：复制一段文字的时候就是长按操作
• 长按事件和单、双击事件也非常类似
• 接口名：LongClickedListener

2. 实现案例：长按按钮修改文本内容

• 新建项目：ListenerApplication3

ability_main

<?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:alignment="center"
    ohos:orientation="vertical">

    <Text
        ohos:id="$+id:text1"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:text="text"
        ohos:text_size="100">

    </Text>

    <Button
        ohos:id="$+id:but1"
        ohos:height="match_content"
        ohos:width="match_content"
        ohos:text="点我"
        ohos:text_size="100"
        ohos:background_element="red">

    </Button>
</DirectionalLayout>

MainAbilitySlice

package com.xdr630.listenerapplication3.slice;

import com.xdr630.listenerapplication3.ResourceTable;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Button;
import ohos.agp.components.Component;
import ohos.agp.components.Text;

public class MainAbilitySlice extends AbilitySlice implements Component.LongClickedListener {
    //提为成员变量，否则onLongClicked访问不到文本组件，并初始化默认值
    Text text1 = null;

    @Override
    public void onStart(Intent intent) {
        super.onStart(intent);
        super.setUIContent(ResourceTable.Layout_ability_main);

        //1.找到文本框组件和按钮组件
        text1 = (Text) findComponentById(ResourceTable.Id_text1);
        Button but1 = (Button) findComponentById(ResourceTable.Id_but1);

        //2.绑定长按事件，点谁就给谁绑定事件
        //当对按钮进行长按操作时，就会执行this本类中onLongClicked方法
        but1.setLongClickedListener(this);
    }

    @Override
    public void onActive() {
        super.onActive();
    }

    @Override
    public void onForeground(Intent intent) {
        super.onForeground(intent);
    }

    @Override
    public void onLongClicked(Component component) {
        //修改文本框的内容
        text1.setText("长按");
    }
}

• 运行：
  
• 长按按钮后：