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LitePal 3.0

添加依赖、配置

  • build.gradle
    implementation 'org.litepal.android:java:3.0.0'

  • AndroidManifest.xml: application添加
    android:name="org.litepal.LitePalApplication"

  • 在app/src/main新建assets/litepal.xml

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    <?xml version="1.0" encoding="utf-8" ?>
    <litepal>
    <!--    数据库名称-->
        <dbname  value="LitePalDemo"/>
    <!--    版本-->
        <version value="1"/>
        <list>
    <!--        注册NewsBean表-->
            <mapping class="com.example.litepaltest.NewsBean"/>
        </list>
    </litepal>

  • 创建NewsBean类(Alt + inserrt)

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    public class NewsBean extends LitePalSupport {

        private String createTime;
        private String title;
        private String content;
        private int number;

        public void setCreateTime(String createTime) {
            this.createTime = createTime;
        }

        public void setTitle(String title) {
            this.title = title;
        }

        public void setContent(String content) {
            this.content = content;
        }

        public void setNumber(int number) {
            this.number = number;
        }

        public String getCreateTime() {
            return createTime;
        }

        public String getTitle() {
            return title;
        }

        public String getContent() {
            return content;
        }

        public int getNumber() {
            return number;
        }
    }

    MainActivity

  • 增加

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    public void release(){
            //添加单条数据，批量可用List, LitePal.saveAll(list)
            NewsBean bean = new NewsBean();
            bean.setCreateTime("20:23");
            bean.setTitle("title");
            bean.setContent("this is content");
            bean.setNumber(200);
            if(bean.save()){
                Toast.makeText(this, "save suceeded", Toast.LENGTH_SHORT).show();
            }else{
                Toast.makeText(this, "save failed", Toast.LENGTH_SHORT).show();
            }
        }

  • 更新

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    private void updateNews() {
            NewsBean newsBean = new NewsBean();
    //        newsBean = LitePal.find(NewsBean.class, 1);
            newsBean.setTitle("new title");
            newsBean.setContent("this is new content");
            newsBean.setToDefault("title"); // 设为 null
            if (newsBean.save()) { //save同newsBean.update(1)
                Toast.makeText(this, "update succeeded", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(this, "update failed", Toast.LENGTH_SHORT).show();
            }
            //newsBean.updateAll("title = ?", "title"};修改所有
            // title为"title"的记录，更新为"new title"
        }

  • 删除

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    private void deleteNews(int position){
    //        LitePal.delete(NewsBean.class, position);
            LitePal.deleteAll(NewsBean.class);//delete all
    //        LitePal.deleteAll(NewsBean.class, "number > ?","100");
    //        LitePal.deleteAll(NewsBean.class, "title = ?", "张三");
    //        LitePal.deleteAll(NewsBean.class, "title = ? and content = ?", "张三", "content");
        }

  • 查询

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    private void queryNews(){
            List<NewsBean> newsBeanList = LitePal.findAll(NewsBean.class);
            NewsBean newsBean = LitePal.find(NewsBean.class, 1);//id为1的记录
            //第一条、最后一条记录
            NewsBean first = LitePal.findFirst(NewsBean.class);
            NewsBean last = LitePal.findLast(NewsBean.class);
            //第5，10，,15条记录
            List<NewsBean> newsList1 = LitePal.findAll(NewsBean.class, 5, 10, 15);
            for(NewsBean list : newsBeanList){
                Log.e("print", "create time: "+list.getCreateTime());
                Log.e("print", "title: "+list.getTitle());
                Log.e("print", "content: "+list.getContent());
                Log.e("print", "number: "+list.getNumber());
                Log.e("print", "sum = "+newsBeanList.size());
                String str = "---------------------------------------------------------";
                System.out.println(str);
            }
        }