我无法使用android从图库中删除图像

Question

我在 android 中有项目，我想从图库中选择多张图像，下一步是删除文件或重命名文件。 但他们都没有工作，我不知道为什么！

    public void fileRename(Uri uri){
    //File file=new File(uri.getPath());
    String[] filePathColumn = { MediaStore.Images.Media.DATA };
    Cursor cursor = getContentResolver().query(uri,
            filePathColumn, null, null, null);
    cursor.moveToFirst();
    File file=new File(cursor.getString(cursor.getColumnIndex(filePathColumn[0])));
    if(file.exists()){
        boolean del=file.delete();
        if(del){
            Toast.makeText(this, "Trueee", Toast.LENGTH_SHORT).show();
        }
    }

Answer 1

我用这段代码解决了问题； 首先在清单中添加此权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE" />

对于 API 29，将此添加到应用程序标记中：

android:requestLegacyExternalStorage="true"

下一步获得用户的许可：

if(!checkPermission()){
        requestPermission();
    }

和功能：

    private void requestPermission() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
        try {
            Intent intent = new Intent(Settings.ACTION_MANAGE_APP_ALL_FILES_ACCESS_PERMISSION);
            intent.addCategory("android.intent.category.DEFAULT");
            intent.setData(Uri.parse(String.format("package:%s",getApplicationContext().getPackageName())));
            startActivityForResult(intent, 2296);
        } catch (Exception e) {
            Intent intent = new Intent();
            intent.setAction(Settings.ACTION_MANAGE_ALL_FILES_ACCESS_PERMISSION);
            startActivityForResult(intent, 2296);
        }
    } else {
        //below android 11
        ActivityCompat.requestPermissions(MainActivity.this, new String[]{WRITE_EXTERNAL_STORAGE}, 10);
    }
}


private boolean checkPermission() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
        return Environment.isExternalStorageManager();
    } else {
        int result = 0;
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            result = context.checkSelfPermission(READ_EXTERNAL_STORAGE);
            int result1 = context.checkSelfPermission(WRITE_EXTERNAL_STORAGE);
            return result == PackageManager.PERMISSION_GRANTED && result1 == PackageManager.PERMISSION_GRANTED;
        }
        }
    return true;
}

并像这样从用户那里获取图像：从用户那里获取图像

然后使用此代码从存储中删除：

    public void fileDelete(Uri uri){

    final String docId;
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
        docId = DocumentsContract.getDocumentId(uri);
        final String[] split = docId.split(":");
        final String type = split[0];

        Uri contentUri = null;

        if ("image".equals(type)) {
            contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        } else if ("video".equals(type)) {
            contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
        } else if ("audio".equals(type)) {
            contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
        }
        String selection = "_id=?";
        String[] selectionArgs = new String[]{split[1]};


        String temp=getDataColumn(context, contentUri, selection,
                selectionArgs);
        File file=new File(temp);
        if(file.exists()){
            if(file.delete()){
                Toast.makeText(context, "deleted", Toast.LENGTH_SHORT).show();
            }
            else{
                Toast.makeText(context, "not Deleted", Toast.LENGTH_SHORT).show();
            }
        }

    }else if(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2){
        String[] filePathColumn = { MediaStore.Images.Media.DATA };
        Cursor cursor = getContentResolver().query(uri,
                filePathColumn, null, null, null);
        cursor.moveToFirst();
        File file=new File(cursor.getString(cursor.getColumnIndex(filePathColumn[0])));
        if(file.exists()){
            if(file.delete()){
                Toast.makeText(this, "deleted", Toast.LENGTH_SHORT).show();
                if(file.exists()){
                    Toast.makeText(this, "Exist", Toast.LENGTH_SHORT).show();
                }
            }
            else Toast.makeText(this, "Not Exist", Toast.LENGTH_SHORT).show();
        }
    }}


private String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
    Cursor cursor = null;
    final String column = "_data";
    final String[] projection = {column};

    try {
        cursor = context.getContentResolver().query(uri, projection,
                selection, selectionArgs, null);

        if (cursor != null && cursor.moveToFirst()) {
            final int index = cursor.getColumnIndexOrThrow(column);
            return cursor.getString(index);
        }
    }
    finally {
        if (cursor != null)
            cursor.close();
    }

    return null;
}