How to retrieve multiple images from Res/draw using BitmapFactory.decodeResource

Question

I need to resize images according to the device screen size.I can do it for single images one at a time,Currently I am dealing with 18 images.The code will be too clumsy and difficult to work out with. Most importantly in my code I need to create a matrix to store the image once created . I am following this link Resize Bitmap image?.

How can I load multiple images so that I can do it easily and more efficiently.

Answer 1

@SuppressLint("NewApi")
    public static int getDeviceWidth(Activity activity) {
        int deviceWidth = 0;

        Point size = new Point();
        WindowManager windowManager = activity.getWindowManager();

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            windowManager.getDefaultDisplay().getSize(size);
            deviceWidth = size.x;
        } else {
            Display display = windowManager.getDefaultDisplay();
            deviceWidth = display.getWidth();
        }
        return deviceWidth;
    }

    @SuppressLint("NewApi")
    public static int getDeviceHeight(Activity activity) {
        int deviceHeight = 0;

        Point size = new Point();
        WindowManager windowManager = activity.getWindowManager();

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            windowManager.getDefaultDisplay().getSize(size);
            deviceHeight = size.y;
        } else {
            Display display = windowManager.getDefaultDisplay();
            deviceHeight = display.getHeight();
        }
        return deviceHeight;
    }

//above function get device width and height

public static Bitmap getBitmapFromPath(String sdCardPath, Activity activity) {
        // TODO Auto-generated method stub
        return decodeSampledBitmapFromResource(sdCardPath,
                getDeviceWidth(activity), getDeviceHeight(activity));
    }

base on getBitmapFromPath() you can set your image as device specific.. call getBitmapFromPath() in your activity when you retrieve path of image.

//edited answer

final R.drawable drawableResources = new R.drawable();
final Class<R.drawable> c = R.drawable.class;
final Field[] fields = c.getDeclaredFields();

for (int i = 0, max = fields.length; i < max; i++) {
    final int resourceId;
    try {
        resourceId = fields[i].getInt(drawableResources);
    } catch (Exception e) {
        continue;
    }
    /* make use of resourceId for accessing Drawables here */
}