Can I Set "android:layout_below" at Runtime Programmatically?

Question

Is it possible when creating a RelativeLayout at runtime to set the equivalent of android:layout_below programmatically?

score 484 · Answer 1 · edited Sep 15 '17 at 07:21

484

Yes:

RelativeLayout.LayoutParams params= new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT); 
params.addRule(RelativeLayout.BELOW, R.id.below_id);
viewToLayout.setLayoutParams(params);

First, the code creates a new layout params by specifying the height and width. The addRule method adds the equivalent of the xml properly android:layout_below. Then you just call View#setLayoutParams on the view you want to have those params.

edited Sep 15 '17 at 07:21

Pankaj Lilan

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answered Jul 18 '10 at 21:20

Rich Schuler

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why can't this answer be accepted ? It's a very good explanation. – Adithya Feb 25 '13 at 18:05
Works for me. Used this approach to add a View ABOVE a view. This answer should be accepted right away. – Rohit Singh Oct 24 '21 at 04:27

jackofallcode · Answer 2 · 2016-06-29T09:08:31.203

154

Alternatively you can use the views current layout parameters and modify them:

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) viewToLayout.getLayoutParams();
params.addRule(RelativeLayout.BELOW, R.id.below_id);

edited Jun 29 '16 at 09:08

answered Feb 11 '14 at 15:22

jackofallcode

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@EelLee It's pretty clearly another way to answer the question, which is why it has 11 upvotes. – Alex K Jan 04 '15 at 20:50
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This should have more upvotes than the other answer: to maintain consistent behavior of the view, we should work with existing `LayoutParams` rather than creating new ones. In fact, this should be accepted as the correct answer. – Kevin Kopf Oct 19 '16 at 21:27

score 13 · Answer 3 · answered Nov 07 '17 at 11:42

13

While @jackofallcode answer is correct, it can be written in one line:

((RelativeLayout.LayoutParams) viewToLayout.getLayoutParams()).addRule(RelativeLayout.BELOW, R.id.below_id);

answered Nov 07 '17 at 11:42

CoolMind

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this doesn't allow you to actually change the layout as you need a reference to the `LayoutParams` to set them with `setLayoutParams` – Stef Nov 18 '18 at 09:30
@Stef, I used this solution in one project. While jackofallcode solution is the only right here, I simplified it. But now I think shortening to one line is not good, because if any exception occurs, it would be harder to understand what operator raised it. – CoolMind Nov 19 '18 at 06:54
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@CoolMind I don't really like shortening code to 1 line, it makes it harder to read, especially when casting is involved. Plus doing it my way allows you to make further changes :) – jackofallcode Aug 15 '19 at 09:38
@jackofallcode, agree with you! Currently I also write in several lines, because when crash happens, it is easier to understand in what line an error occured. – CoolMind Aug 15 '19 at 10:12

Mahmoud · Answer 4 · 2020-04-28T21:37:01.870

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Kotlin version with infix function

infix fun View.below(view: View) {
      (this.layoutParams as? RelativeLayout.LayoutParams)?.addRule(RelativeLayout.BELOW, view.id)
}

Then you can write:

view1 below view2

Or you can call it as a normal function:

view1.below(view2)

edited Apr 28 '20 at 21:37

answered Apr 28 '20 at 21:00

Mahmoud

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Can I Set "android:layout_below" at Runtime Programmatically?

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