HarmonyOS应用开发实战-JS访问本地图片 原创

选择鸿蒙api7 提供获取读取本地文件的api，但api7还未稳定，我们可以使用java api将想要的文件复制到js现在可以访问的internal://app/下，在使用js访问。
//存储照片到js可以访问的目录下
void setImaData(Uri uri,String name){

    String imgName ="/"+name+".jpg";


    requestPermissionsFromUser(new String[]{"ohos.permission.READ_USER_STORAGE"},1234);
    HiLog.info(TAG,"私有目录:"+this.getFilesDir());
    HiLog.info(TAG,"缓存目录:"+this.getCacheDir());
    HiLog.info(TAG,"数据目录:"+this.getDataDir());
    HiLog.info(TAG,"外部目录:"+this.getExternalCacheDir());
    HiLog.info(TAG,"引用目录:"+this.getPreferencesDir());
    HiLog.info(TAG,"同步目录:"+this.getDistributedDir());
    HiLog.info(TAG,"应用目录:"+this.getDir("", Context.MODE_PRIVATE));
    File[] dataChildFiles = this.getDataDir().listFiles();
    for (File dataChildFile : dataChildFiles) {
        HiLog.info(TAG,"数据子目录:"+dataChildFile);
    }
    File[] externalFiles=this.getExternalMediaDirs();
    for (File externalFile : externalFiles) {
        HiLog.info(TAG,"外部Media目录:"+externalFile);
    }

    try {
        //该目录和JSUI中的internal://cache/目录是一个目录

// File file=new File(this.getCacheDir()+“/111.png”);
File file=new File(this.getFilesDir()+imgName);
HiLog.info(TAG,“文件路径:”+file);
if(file.exists())
{
HiLog.info(TAG,“文件已存在”);
setUriToService(imgName);
return;
}
HiLog.info(TAG,“文件不存在”);

        //定义数据能力帮助对象
        DataAbilityHelper helper=DataAbilityHelper.creator(getContext());
        //读取图片
        FileDescriptor fd = null;
        try {
            fd = helper.openFile(uri, "r");
        } catch (DataAbilityRemoteException e) {
            e.printStackTrace();
        }

        ImageSource imageSource;
        imageSource = ImageSource.create(fd, null);


        // 设置图片参数
        ImageSource.DecodingOptions decodingOptions = new ImageSource.DecodingOptions();
        decodingOptions.desiredSize=new Size(200,200);
        imageSource.createPixelmap(decodingOptions);
        //该种方式直接访问internal://app目录

// FileOutputStream fos=new FileOutputStream(“/data/user/0/com.example.abilitytransfertest/files//111.jpg”);
FileOutputStream fos=new FileOutputStream(this.getFilesDir()+imgName);

        ImagePacker imagePacker = ImagePacker.create();
        ImagePacker.PackingOptions packingOptions = new ImagePacker.PackingOptions();
        packingOptions.format = "image/jpeg";
        packingOptions.quality = 90;
        boolean result = imagePacker.initializePacking(fos, packingOptions);
        if(result)
        {
            result = imagePacker.addImage(imageSource.createPixelmap(decodingOptions));
            if (result) {
                long dataSize = imagePacker.finalizePacking();
                HiLog.info(TAG,"文件大小："+dataSize);
            }
        }

        fos.flush();
        fos.close();
        if(file.exists())
        {
            HiLog.info(TAG,"文件已存在");
            setUriToService(imgName);
            return;
        }
    } catch (IOException e) {
        HiLog.info(TAG,"文件保存出错："+e.getMessage());
        e.printStackTrace();
    }

    File file=this.getFilesDir();
    File[] files = file.listFiles();
    for (File file1 : files) {
        HiLog.info(TAG,"File目录:"+file1);
    }
}