如何从内部存储中删除文件

Question

我需要从内部存储中删除文件。 以下代码用于创建文件。

 Picasso.with(mContext).load(imageurl).into(new Target() {
                                @Override
                                public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {

                                    try {
                                        String root = Environment.getExternalStorageDirectory().toString();
                                        File myDir = new File(root + "/Omoto Images");
                                        if (!myDir.exists()) {
                                            myDir.mkdirs();
                                        }
                                        String name = imagename;
                                        myDir = new File(myDir, name);
                                        FileOutputStream out = new FileOutputStream(myDir);
                                        bitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
                                        out.flush();
                                        out.close();
                                    } catch (Exception e) {

                                    }
                                }

                                @Override
                                public void onBitmapFailed(Drawable errorDrawable) {
                                }

                                @Override
                                public void onPrepareLoad(Drawable placeHolderDrawable) {
                                }
                            });

以下代码用于删除

    String root = Environment.getExternalStorageDirectory().toString();
                                        File myDir = new File(root + "/Omoto Images");

myDir.delete（）;

但删除无效