Changing position of the Dialog on screen android

New BottomSheetDialog:

BottomSheetDialog dialog = new BottomSheetDialog(YourActivity.this);    
dialog.setContentView(YourView);

dialog.show();

I used this code to show the dialog at the bottom of the screen:

Dialog dlg = <code to create custom dialog>;

Window window = dlg.getWindow();
WindowManager.LayoutParams wlp = window.getAttributes();

wlp.gravity = Gravity.BOTTOM;
wlp.flags &= ~WindowManager.LayoutParams.FLAG_DIM_BEHIND;
window.setAttributes(wlp);

This code also prevents android from dimming the background of the dialog, if you need it. You should be able to change the gravity parameter to move the dialog about

I found this code snippet from @gypsicoder code here

private CharSequence[] items = {"Set as Ringtone", "Set as Alarm"};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setItems(items, new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int item) {

        if(item == 0) {

        } else if(item == 1) {

        } else if(item == 2) {

        }
    }
});

AlertDialog dialog = builder.create();
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
WindowManager.LayoutParams wmlp = dialog.getWindow().getAttributes();

wmlp.gravity = Gravity.TOP | Gravity.LEFT;
wmlp.x = 100;   //x position
wmlp.y = 100;   //y position

dialog.show();

Here x position's value is pixels from left to right. For y position value is from bottom to top.

private void showPictureialog() {
    final Dialog dialog = new Dialog(this,
            android.R.style.Theme_Translucent_NoTitleBar);

    // Setting dialogview
    Window window = dialog.getWindow();
    window.setGravity(Gravity.CENTER);

    window.setLayout(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
    dialog.setTitle(null);
    dialog.setContentView(R.layout.selectpic_dialog);
    dialog.setCancelable(true);

    dialog.show();
}

you can customize you dialog based on gravity and layout parameters change gravity and layout parameter on the basis of your requirenment