Android SQLite image Storage

问题

I am making a quiz app which requires me to be able to get an image from a database BLOB or image path stored in the database. However i have looked around and a lot of people suggest using a file path, the problem is i don't know where to store the image if i use the file path method.

Do i store it somewhere in the app such as the resources folder?, a lot of examples use SD cards but is it possible to save an image to SD card from a database and if so surely that would mean i have two images one in database and one on SD card.

Where is the best place to store a images for a quiz app that i can use on any phone an will have access to said images? and how ?.

Thanks in advance.

回答1:

Image storage must be performed in some directory and the corresponding paths of the image must be stored in the database.

There will be times when you will accessing your images from one acivity then the other, in that case you will just need to pass the path of the image from activity one to activity two and then retrieve the image from the directory to display in activity two. Image storing and loading from databases may turn out to be a pain when the size of the images will start increasing. For learning how to store images, Give an eye to this

CODE EXAMPLE

private void SaveImage(Bitmap finalBitmap) {

String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/saved_images");    
myDir.mkdirs();
Random generator = new Random();
int n = 10000;
n = generator.nextInt(n);
String fname = "Image-"+ n +".jpg";
File file = new File (myDir, fname);
if (file.exists ()) file.delete (); 
try {
       FileOutputStream out = new FileOutputStream(file);
       finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
       out.flush();
       out.close();

} catch (Exception e) {
       e.printStackTrace();
}

}

In the above code, the line

 Environment.getExternalStorageDirectory()

is refering to android/data folder. you can create folder inside upto any level, like android/data/folderone/folderTwo/folderThree .

Note: However you need to first fetch the images from server for the first time and store them in device.If you are thinking of bundling up the images along with the app, put all of your images in res/drawable folders.(if no web server functionality is involved)

来源：https://stackoverflow.com/questions/36379926/android-sqlite-image-storage

标签

android

image

sqlite

filepath