Android /布局-实用地将边距顶部添加到相对布局

Question

I'm trying to add pragmatically a margin top to my Relative Layout in my activity. Using the xml i can do it in this mode: android:layout_marginTop="10dp" , but when i'm trying to do it pragmatically nothing change...

This is the code that i'm using:

//SCROLL VIEW
        ScrollView scrollView = new ScrollView(this);
        scrollView.setBackground(getResources().getDrawable(R.drawable.background));
        scrollView.setLayoutParams(new ScrollView.LayoutParams(ScrollView.LayoutParams.MATCH_PARENT,
                                                     ScrollView.LayoutParams.MATCH_PARENT));
        scrollView.setPadding(20, 20, 20, 20);

        //LINEAR LAYOUT
        LinearLayout linearLayout = new LinearLayout(this);
        linearLayout.setOrientation(LinearLayout.VERTICAL);
        linearLayout.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
                LinearLayout.LayoutParams.WRAP_CONTENT));

        for (int i=1; i<=3; i++){
        //RELATIVE LAYOUT
        RelativeLayout relativeLayout = new RelativeLayout(this);
        relativeLayout.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT,
                RelativeLayout.LayoutParams.FILL_PARENT));
        relativeLayout.setBackgroundColor(getResources().getColor(R.color.grayColor));

        RelativeLayout.LayoutParams head_params = (RelativeLayout.LayoutParams)relativeLayout.getLayoutParams();
        head_params.setMargins(0, 80, 0, 0);
        relativeLayout.setLayoutParams(head_params);

        //Need to understand how put a margin top to the relativeLayout

        //IMAGE VIEW
        ImageView selectedPhoto = new ImageView(this);
        selectedPhoto.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT));
        selectedPhoto.setImageResource(R.drawable.ic_launcher);


        //TEXT VIEWS
        TextView numberCopies = new TextView(this);
        numberCopies.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT));
        numberCopies.setGravity(Gravity.CENTER);
        numberCopies.setPadding(25, 25, 25, 25);
        numberCopies.setTextColor(getResources().getColor(R.color.blackColor));
        numberCopies.setText("2 copies ");
        RelativeLayout.LayoutParams layoutParamsNumberCopies = (RelativeLayout.LayoutParams) numberCopies.getLayoutParams();
        layoutParamsNumberCopies.addRule(RelativeLayout.CENTER_HORIZONTAL);
        numberCopies.setLayoutParams(layoutParamsNumberCopies);

        TextView priceCopies = new TextView(this);
        priceCopies.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT));
        priceCopies.setGravity(Gravity.CENTER);
        numberCopies.setPadding(25, 25, 25, 25);
        priceCopies.setTextColor(getResources().getColor(R.color.redColor));
        priceCopies.setText("$ 25 ");
        RelativeLayout.LayoutParams layoutParamsPriceCopies = (RelativeLayout.LayoutParams) priceCopies.getLayoutParams();
        layoutParamsPriceCopies.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
        priceCopies.setLayoutParams(layoutParamsPriceCopies);


        relativeLayout.addView(selectedPhoto);
        relativeLayout.addView(numberCopies);
        relativeLayout.addView(priceCopies);
        linearLayout.addView(relativeLayout);
        }
        scrollView.addView(linearLayout);
        setContentView(scrollView);

}

I have tried also relativeLayout.setMargins(20, 0, 0, 0); but seems that this method isn't available for relativeLayout. I'm not sure about it.

Thanks

Answer 1

Change your setmargins line to

head_params.setMargins(0, 80, 0, 0);

Margin parameters go clockwise starting with the left margin, ie (left, top, right, bottom). However, if you have other margins other than the top one, this will delete them. A much easier and more intuitive way is to simply write

header_params.topMargin=80;

Also not to forget, you never set your header_params back to your view. Add this line below:

relativeLayout.setLayourParams(header_params);

Answer 2

Try this

RelativeLayout.LayoutParams head_params = (RelativeLayout.LayoutParams)headView.getLayoutParams();
head_params.setMargins(0, 80, 0, 0);//substitute parameters for left, top, right, bottom