Android简单轮播

阳光穿透心脏的1/2处 2022-12-11 05:20 173阅读 0赞

一般传统的安卓应用都会用到轮播，主要用于广告、商品图片展示等等，可以说占了主页面一个挺重要的部分。

我用的开发工具是android studio+Eclipse，基于ssm框架。

这里用到了一个banner开源插件，开源地址是：

[https://github.com/youth5201314/banner][https_github.com_youth5201314_banner]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDU0NDU5NA_size_16_color_FFFFFF_t_70][]

首先第一步，找到android studio项目中Gradle Scripts下的build.gradle，然后把依赖添加到dependencies标签内。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDU0NDU5NA_size_16_color_FFFFFF_t_70 1][]

第二步，在xml文件里面引用

<com.youth.banner.Banner
                xmlns:app="http://schemas.android.com/apk/res-auto"
                android:id="@+id/banner_home_header"
                android:layout_width="match_parent"
                android:layout_height="180dp" />

简单写一个数据库

![20200928162701342.png][]

接着，去eclipse服务端写查询方法

数据库查询语句

<select id="selectAllBanner" resultMap="BaseResultMap">
      	select banner.*
      	from banner
      	where is_show =1 and is_valid =1
      </select>

实现接口类和dao就不写了，和普通的查询一样

控制器：

package com.mm.web;
    
    import java.io.File;
    import java.io.IOException;
    import java.util.List;
    
    import org.apache.commons.io.FileUtils;
    import org.apache.commons.io.FilenameUtils;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.HttpHeaders;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.ResponseEntity;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    import com.google.gson.Gson;
    import com.google.gson.GsonBuilder;
    import com.mm.po.Banner;
    import com.mm.service.IAppMainPageService;
    import com.mm.util.AppSeting;
    import com.mm.util.Tools;
    
    @Controller
    @RequestMapping("/app/mainPage")
    public class AppMainPageController {
    	
    	//处理json
    	private Gson gson = new GsonBuilder().setDateFormat("yyyy-MM-dd HH:mm:ss").create();
    	
    	//注入service
    	@Autowired
    	IAppMainPageService appMainPageService;
    	
    	/**
    	 * App查询轮播
    	 */
    	@RequestMapping(value="/getBannerInfo")
    	@ResponseBody
    	public Object getBannerInfo() {
    		List<Banner> banners=this.appMainPageService.selectBannerAll();
    		return gson.toJson(banners);
    	}
    	
    	/**
    	 * app获取
    	 */
    	@RequestMapping(value="/getBannerPicture")
    	public ResponseEntity<byte[]> getBannerPicture(String pictureName) throws IOException{
    		if(Tools.isNotNull(pictureName)) {
    			//文件
    			File file=new File(AppSeting.UPLOAD_MAIN_BANNER_DIR,pictureName);
    			if(file.exists()) {//判断文件是否存在
    				//设置header
    				HttpHeaders headers=new HttpHeaders();
    				//设置为图片类型
    				headers.setContentType(MediaType.IMAGE_JPEG);
    				headers.setContentDispositionFormData("attachment", pictureName);
    
    				//返回文件相关数据
    				return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),headers,HttpStatus.CREATED);
    			}
    		}
    		return null;
    	}
    
    }

定义了一个轮播图片存放路径的class：AppSeting

package com.mm.util;
    
    public class AppSeting {
    
    	/**
    	 * 轮播图片存放路径
    	 */
    	public static final String UPLOAD_MAIN_BANNER_DIR = "E:\\mycode\\eclipse\\CargoService\\src\\main\\webapp\\images\\mainBanner";
    	public static final String UPLOAD_MEMBER_PHOTO_DIR = "E:\\mycode\\eclipse\\CargoService\\src\\main\\webapp\\images\\memberPhone";
    	public static final String UPLOAD_ROOM_TYPE_PIC_DIR = "E:\\mycode\\eclipse\\CargoService\\src\\main\\webapp\\images\\roomTypePic";
    }

具体路径改成自己的本地路径

回到android studio，初始化界面，加载轮播

//初始化页面
        private void initView() {
            //显示轮播
            //获取服务端轮播数据
            String url= ServiceUrls.getMainPageMethodUrl("getBannerInfo");
            //发送请求
            OkHttpTool.httpPost(url, null, new OkHttpTool.ResponseCallback() {
                @Override
                public void onResponse(final boolean isSuccess, final int responseCode, final String response, Exception exception) {
                    mActivityContext.runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            if (isSuccess && responseCode==200 && Tools.isNotNull(response)){
                                Type type=new TypeToken<List<BannerBean>>(){}.getType();
                                List<BannerBean> bannerList=gson.fromJson(response,type);
    
                                //显示轮播
                                bannerHeader.setAdapter(new HomeBannerAdapter(bannerList,mActivityContext))
                                        .setIndicator(new CircleIndicator(mActivityContext))//设置圆形指示器
                                        .setIndicatorSelectedColorRes(R.color.dodgerblue)//设置被选中指示器的颜色
                                        .isAutoLoop(true)//自动开启轮播
                                        //.setDelayTime(10*1000)//轮播间隔
                                        .setOnBannerListener(new OnBannerListener() {
                                            @Override
                                            public void OnBannerClick(Object data, int position) {
                                                int bannerId=((BannerBean)data).getBannerId();
                                                Toast.makeText(mActivityContext,String.valueOf(bannerId),Toast.LENGTH_SHORT).show();
                                            }
                                        });
                            }else{
                                Toast.makeText(mActivityContext,"轮播加载失败",Toast.LENGTH_LONG).show();
                            }
                        }
                    });
                }
            });
        }

模拟器运行效果

![20200928203557233.gif][]

[https_github.com_youth5201314_banner]: https://github.com/youth5201314/banner
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDU0NDU5NA_size_16_color_FFFFFF_t_70]: /images/20221123/3ab01d8ba1cd432db31161e0d5d76686.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDU0NDU5NA_size_16_color_FFFFFF_t_70 1]: /images/20221123/323c0aa528d946eab26a5ac6759bf9a5.png
[20200928162701342.png]: /images/20221123/aa064c36c9f9429ca5eda05b0a4b774b.png
[20200928203557233.gif]: /images/20221123/dee406a4b8304fd59796491006170b47.png