HarmonyOS实战一原子化服务初尝试(ClockFACardDemo学习)

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。

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