适配Android 11 动态申请外部存储权限，解决open f

突然发现以前在application中通过添加android:requestLegacyExternalStorage="true"的配置在Android11上面无效了，所以只能添加动态申请的过程了，具体如下：

注意：需要将CompileSdkVersion升级到30以上，否则无法使用部分api。

private static final int REQUEST_CODE = 1024;
    private void requestPermission() {
        if (Build.VERSION.SDK_INT >= 30 ){
            // 先判断有没有权限
            if (Environment.isExternalStorageManager()) {
                writeFile();
            } else {
                Intent intent = new Intent(Settings.ACTION_MANAGE_APP_ALL_FILES_ACCESS_PERMISSION);
                intent.setData(Uri.parse("package:" +getApplication().getPackageName()));
                startActivityForResult(intent, REQUEST_CODE);
            }
        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            // 先判断有没有权限
            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED &&
                    ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
                writeFile();
            } else {
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CODE);
            }
        } else {
            writeFile();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == REQUEST_CODE) {
            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED &&
                    ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
                writeFile();
            } else {
                Toast.makeText(this,"存储权限获取失败",Toast.LENGTH_LONG).show();;
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_CODE && Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
            if (Environment.isExternalStorageManager()) {
                writeFile();
            } else {
                Toast.makeText(this,"存储权限获取失败",Toast.LENGTH_LONG).show();;

            }
        }
    }

    /**
     * 模拟文件写入
     */
    private void writeFile() {
        Toast.makeText(this,"success",Toast.LENGTH_LONG).show();;

    }

当然也可以使用郭神的PermissionX框架，传送门：https://blog.csdn.net/guolin_blog/article/details/119055926?spm=1001.2014.3001.5501