How to set margin of ImageView using code, not xml

Kevin's code creates redundant MarginLayoutParams object. Simpler version:

ImageView image = (ImageView) findViewById(R.id.main_image);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(image.getLayoutParams());
lp.setMargins(50, 100, 0, 0);
image.setLayoutParams(lp);

android.view.ViewGroup.MarginLayoutParams has a method setMargins(left, top, right, bottom). Direct subclasses are: FrameLayout.LayoutParams, LinearLayout.LayoutParams and RelativeLayout.LayoutParams.

Using e.g. LinearLayout:

LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
lp.setMargins(left, top, right, bottom);
imageView.setLayoutParams(lp);

MarginLayoutParams

This sets the margins in pixels. To scale it use

context.getResources().getDisplayMetrics().density

DisplayMetrics

All the above examples will actually REPLACE any params already present for the View, which may not be desired. The below code will just extend the existing params, without replacing them:

ImageView myImage = (ImageView) findViewById(R.id.image_view);
MarginLayoutParams marginParams = (MarginLayoutParams) image.getLayoutParams();
marginParams.setMargins(left, top, right, bottom);

    image = (ImageView) findViewById(R.id.imageID);
    MarginLayoutParams marginParams = new MarginLayoutParams(image.getLayoutParams());
    marginParams.setMargins(left_margin, top_margin, right_margin, bottom_margin);
    RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(marginParams);
    image.setLayoutParams(layoutParams);