harmonyos实战一原子化服务初尝试(clockfacarddemo学习)-yb体育官方

卡片数据服务：为了方便处理·时钟卡片刷新的定时任务，我们创建了一个service ability，定时去更新卡片信息，在timerability.java中

package com.huawei.cookbooks;
import com.huawei.cookbooks.database.form;
import com.huawei.cookbooks.database.formdatabase;
import com.huawei.cookbooks.utils.componentproviderutils;
import com.huawei.cookbooks.utils.databaseutils;
import ohos.aafwk.ability.ability;
import ohos.aafwk.ability.formexception;
import ohos.aafwk.content.intent;
import ohos.agp.components.componentprovider;
import ohos.data.databasehelper;
import ohos.data.orm.ormcontext;
import ohos.data.orm.ormpredicates;
import ohos.hiviewdfx.hilog;
import ohos.hiviewdfx.hiloglabel;
import ohos.rpc.iremoteobject;
import java.util.list;
import java.util.timer;
import java.util.timertask;
/**
 * time pa  时钟更新service ability。
 */
public class timerability extends ability {
    private static final hiloglabel label_log = new hiloglabel(3, 0xd001100, "demo");
    private static final long send_period = 1000l;
    private databasehelper helper = new databasehelper(this);
    private ormcontext connect;
    @override
    public void onstart(intent intent) {
        hilog.info(label_log, "timerability::onstart");
        connect = helper.getormcontext("formdatabase", "formdatabase.db", formdatabase.class);
        starttimer();
        super.onstart(intent);
    }
    // 卡片更新定时器，每秒更新一次
    private void starttimer() {
        timer timer = new timer();
        timer.schedule(
                new timertask() {
                    @override
                    public void run() {
                        updateforms();
                    }
                },
                0,
                send_period);
    }
    private void updateforms() {
        // 从数据库中获取卡片信息
        ormpredicates ormpredicates = new ormpredicates(form.class);
        list<form> formlist = connect.query(ormpredicates);
        // 更新时分秒
        if (formlist.size() <= 0) {
            return;
        }
        for (form form : formlist) {
            // 遍历卡片列表更新卡片
            componentprovider componentprovider = componentproviderutils.getcomponentprovider(form, this);
            try {
                long updateformid = form.getformid();
                updateform(updateformid, componentprovider);
            } catch (formexception e) {
                // 删除不存在的卡片
                databaseutils.deleteformdata(form.getformid(), connect);
                hilog.error(label_log, "onupdateform updateform error");
            }
        }
    }
    @override
    public void onbackground() {
        super.onbackground();
        hilog.info(label_log, "timerability::onbackground");
    }
    @override
    public void onstop() {
        super.onstop();
        hilog.info(label_log, "timerability::onstop");
    }
}

有关卡片组件的更新，封装了componentproviderutils这个类，在卡片更新时候，通过调用updateform方法，传入参数formid和componentprovider.

package com.huawei.cookbooks.utils;
import com.huawei.cookbooks.resourcetable;
import com.huawei.cookbooks.database.form;
import ohos.agp.components.componentprovider;
import ohos.agp.utils.color;
import ohos.app.context;
import java.util.calendar;
/**
 * component providerutils 提供获取componentprovider对象的方法，用于卡片组件的更新。
 */
public class componentproviderutils {
    // 当前星期颜色
    private static color nowweekcolor = new color(color.rgb(255, 245, 238));
    // 原色星期
    private static color primaryweekcolor = new color(color.rgb(192, 192, 192));
    private static final int week_days = 7;
    private static final int string_length = 2;
    private static final int dim_version = 3;
    private static final int sunday = 1;
    private static final int monday = 2;
    private static final int tuesday = 3;
    private static final int wednesday = 4;
    private static final int thursday = 5;
    private static final int friday = 6;
    private static final int saturday = 7;
    /**
     * obtain the day of the week
     *
     * @return week
     */
    public static int getweekdayid() {
        calendar calendar = calendar.getinstance();
        int week = calendar.get(calendar.day_of_week);
        int result = getweekidresult(week);
        return result;
    }
    /**
     * get week component id
     *
     * @param week week
     * @return component id
     */
    private static int getweekidresult(int week) {
        int result = resourcetable.id_mon;
        switch (week) {
            case sunday:
                result = resourcetable.id_sun;
                break;
            case monday:
                result = resourcetable.id_mon;
                break;
            case tuesday:
                result = resourcetable.id_tue;
                break;
            case wednesday:
                result = resourcetable.id_wed;
                break;
            case thursday:
                result = resourcetable.id_thu;
                break;
            case friday:
                result = resourcetable.id_fri;
                break;
            case saturday:
                result = resourcetable.id_sat;
                break;
            default:
                result = resourcetable.id_sun;
                break;
        }
        return result;
    }
    /**
     * obtains the componentprovider object
     *
     * @param form form info
     * @param context context
     * @return component provider
     */
    public static componentprovider getcomponentprovider(form form, context context) {
        int layoutid = resourcetable.layout_form_image_with_info_date_card_2_2;
        if (form.getdimension() == dim_version) {
            layoutid = resourcetable.layout_form_image_with_info_date_card_2_4;
        }
        componentprovider componentprovider = new componentprovider(layoutid, context);
        setcomponentprovidervalue(componentprovider);
        return componentprovider;
    }
    /**
     * time converted to string
     *
     * @param time time
     * @return time string
     */
    private static string int2string(int time) {
        string timestring;
        if (string.valueof(time).length() < string_length) {
            timestring = "0"  time;
        } else {
            timestring = time  "";
        }
        return timestring;
    }
    /**
     * set the value of componentprovider
     *
     * @param componentprovider component provider
     */
    private static void setcomponentprovidervalue(componentprovider componentprovider) {
        calendar now = calendar.getinstance();
        int hour = now.get(calendar.hour_of_day);
        int min = now.get(calendar.minute);
        int second = now.get(calendar.second);
        string hourstring = int2string(hour);
        string minstring = int2string(min);
        string secondstring = int2string(second);
        componentprovider.settext(resourcetable.id_date, dateutils.getcurrentdate("yyyy-mm-dd"));
        componentprovider.settext(resourcetable.id_hour, hourstring);
        componentprovider.settext(resourcetable.id_min, minstring);
        componentprovider.settext(resourcetable.id_sec, secondstring);
        // 获取当前星期
        int weekdayid = getweekdayid();
        componentprovider.settextcolor(weekdayid, nowweekcolor);
        // 将前一天的星期改回原色
        int lastweekid = getlastweekdayid();
        componentprovider.settextcolor(lastweekid, primaryweekcolor);
    }
    /**
     * obtain previous day of the week
     *
     * @return previous day of the week
     */
    public static int getlastweekdayid() {
        calendar calendar = calendar.getinstance();
        int week = calendar.get(calendar.day_of_week);
        int lastweek;
        if (week == 1) {
            lastweek = week_days;
        } else {
            lastweek = week - 1;
        }
        return getweekidresult(lastweek);
    }
}

对于服务卡片我们就先学的这里，学完了demo，小伙伴是不是蠢蠢欲动呢？自己写一个类似的demo应该是在可能完成的范围之内的，感兴趣的小伙伴赶快试试吧。之后我准备基于官方的一个demo(一个音频播放器)，搞一个服务卡片。嗯，时间关系，今天就先搞到这里。