Adding full permission for a image file in android.

Question

I am using the following code for adding full permission for the image files in android. This code is not working in every time. Imagine there are three image file, A.png,B.

Answer 1

If you don't have read, write permissions from the context you are running, you will not be able to do chmod from the same context. Change to super user(su. For this the device must be rooted) and then you can change the mode. Here is the code. It works. I tested it. Thanks

void gainRoot()
{
    Process chperm;
    try {
        chperm=Runtime.getRuntime().exec("su");
          DataOutputStream os = 
              new DataOutputStream(chperm.getOutputStream());
            os.writeBytes("chmod 777 /data/data/com.android.settings/MyApp/A.png\n");
            os.flush();
            os.writeBytes("chmod 777 /data/data/com.android.settings/MyApp/B.png\n");
            os.flush();
            os.writeBytes("chmod 777 /data/data/com.android.settings/MyApp/C.png\n");
            os.flush();

              os.writeBytes("exit\n");
              os.flush();

              chperm.waitFor();

    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

Use the code exactly and check if your device is rooted. It shhould work. Call gainRoot() from oncreate(). Let me know in case you have any difficulty. Thanks