Android はイメージ パス/リフレクションを取得して、Uri に従ってシステム プロパティを取得します

1.システムプロパティを取得するためのリフレクション

fun getModel(): String {
        val def = "unknown"
        try {
            Class.forName("android.os.SystemProperties").apply {
                return getDeclaredMethod("get", String::class.java).invoke(
                    this,
                    "ro.product.model"
                )?.toString() ?: def
            }
        } catch (e: Exception) {
            return def
        }
    }

 2. Uri に従って画像パスを取得する

import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.provider.MediaStore;
import android.text.TextUtils;

import com.apex.zhxtapp.staff.base.StaffApplication;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class FileUtil {

    //应用安装路径下的"FileSave"文件夹
    private static final String DIR_AVIC_STAFF = StaffApplication.getInstance()
            .getExternalFilesDir("FileSave") + File.separator;

    //获取AvicStaff文件夹
    public static String getDirAvicStaff() {

        File fileDirRoot = new File(DIR_AVIC_STAFF);
        if (fileDirRoot.exists() && fileDirRoot.isDirectory()) return fileDirRoot.getAbsolutePath();
        else {

            boolean bCreateResult = fileDirRoot.mkdirs();
            if (bCreateResult) return fileDirRoot.getAbsolutePath();
            else {
                //二次创建
                boolean bCreateTwice = fileDirRoot.mkdirs();
                return bCreateTwice ? fileDirRoot.getAbsolutePath() : null;
            }
        }
    }

    /**
     * 根据uri获取路径
     *
     * @param uri 原始uri
     */
    public static String getFilePathFromUri(Context context, Uri uri) {
        if (uri == null) {
            return "";
        }
        switch (uri.getScheme()) {
            case "content":
                return getFileFromContentUri(context, uri);
            case "file":
                return uri.getPath();
            default:
                return "";
        }
    }

    /**
     * 根据Uri获取路径
     *
     * @param contentUri 输入的uri
     */
    private static String getFileFromContentUri(Context context, Uri contentUri) {

        if (contentUri == null) {
            return null;
        }
        File file;
        String filePath = "";
        String fileName;
        String[] filePathColumn = {MediaStore.MediaColumns.DATA, MediaStore.MediaColumns.DISPLAY_NAME};
        ContentResolver contentResolver = context.getContentResolver();
        Cursor cursor = contentResolver.query(contentUri, filePathColumn, null,
                null, null);
        if (cursor != null) {
            cursor.moveToFirst();
            int index = cursor.getColumnIndex(filePathColumn[0]);
            //这里有可能为空 所以要做判断
            if (index > -1) {
                filePath = cursor.getString(index);
            }

            fileName = cursor.getString(cursor.getColumnIndex(filePathColumn[1]));
            cursor.close();

            if (!TextUtils.isEmpty(filePath)) {
                file = new File(filePath);
                if (!file.exists() || file.length() <= 0) {
                    filePath = getPathFromInputStreamUri(context, contentUri, fileName);
                }
            } else {
                filePath = getPathFromInputStreamUri(context, contentUri, fileName);
            }
        }
        return filePath;
    }

    /**
     * 用流拷贝文件一份到自己APP目录下
     */
    private static String getPathFromInputStreamUri(Context context, Uri uri, String fileName) {
        InputStream inputStream = null;
        String filePath = null;

        if (uri.getAuthority() != null) {
            try {
                inputStream = context.getContentResolver().openInputStream(uri);
                File file = createTemporalFileFrom(inputStream, fileName);
                filePath = file.getPath();

            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (inputStream != null) {
                        inputStream.close();
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }

        return filePath;
    }

    /**
     * 将文件通过流的方式复制到临时文件夹
     */
    private static File createTemporalFileFrom(InputStream inputStream, String fileName)
            throws IOException {
        File targetFile = null;

        if (inputStream != null) {
            int read;
            byte[] buffer = new byte[8 * 1024];
            //自己定义拷贝文件路径
            targetFile = new File(getDirAvicStaff(), fileName);
            if (targetFile.exists()) {
                boolean bDel = targetFile.delete();
                if (!bDel) targetFile.delete();
            }
            OutputStream outputStream = new FileOutputStream(targetFile);

            while ((read = inputStream.read(buffer)) != -1) {
                outputStream.write(buffer, 0, read);
            }
            outputStream.flush();

            try {
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        return targetFile;
    }
}

おすすめ

転載: blog.csdn.net/nsacer/article/details/120158516