Add a child view to a parent layout with the same bounds

Question

In a RelativeLayout I have 2 buttons: button and button2. These 3 itself lie inside the root view which is also a RelativeLayout.

What I am trying to accomplish here is that when button is clicked button2 should be removed from the inner RelativeLayout(its id is otherLayout) and get added to the root View which is rootView but with the same bounds as it was in the inner layout.

Here is my XML and Java code:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/rootView"
    tools:context="com.test.testproject.MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/otherLayout"
        >
        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
            android:layout_alignParentTop="true"
            android:layout_marginStart="53dp"
            android:layout_marginTop="94dp"
            android:text="One" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBottom="@+id/button"
            android:layout_marginStart="76dp"
            android:layout_toEndOf="@+id/button"
            android:text="Two" />

    </RelativeLayout>

</RelativeLayout>

Java Code

public class MainActivity extends AppCompatActivity {

    Button button,button2;

    int mLeft,mRight,mTop,mBottom;
    RelativeLayout otherLayout;
    RelativeLayout rootView;
    ViewGroup childParent;
    int[] mBounds = new int[2];

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        button = (Button) findViewById(R.id.button);
        button2 = (Button) findViewById(R.id.button2);
//        rootView = (RelativeLayout) findViewById(R.id.rootView);
        rootView = (RelativeLayout) findViewById(R.id.rootView);
        otherLayout = (RelativeLayout) findViewById(R.id.otherLayout);


        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Rect r = new Rect();

                button2.getLocalVisibleRect(r);
//                button2.getDrawingRect(r);
//                ((ViewGroup)button2.getParent()).offsetDescendantRectToMyCoords(button2, r);

                mLeft = r.left;
                mRight = r.right;
                mBottom = r.bottom;
                mTop = r.top;

                childParent = (ViewGroup) button2.getParent();


                ((ViewGroup)button2.getParent()).removeView(button2);

                Handler mHandler = new Handler(Looper.getMainLooper());

                mHandler.postDelayed(new Runnable() {
                    @Override
                    public void run() {


                        button2.setTop(mTop);
                        button2.setLeft(mLeft);
                        button2.setBottom(mBottom);
                        button2.setRight(mRight);

/*
                        button2.setX(mBounds[1]);
                        button2.setY(mBounds[0]);*/


                        ((ViewGroup)rootView).addView(button2);
                    }
                },1000);

            }
        });

    }
}

I tried a different methods but would work. I used getLocalVisibleRect(), getDrawingRect() and all (You can see in the commented code).

So how do I achieve this? Remember, that the requirement is that the View residing in the inner layout and after adding to root should have the same bounds and params and the position on screen also must not change.

Answer 1

I think that your issue may be with the layout parameters of button2. Probably the easiest way to approach this is to capture the position of button2 in the layout and set up new layout parameters. mLeft and mTop to be the left and top margins.

A simplified onCreate method is below, but I am curious about why this would be useful.

Also take a look at these caveats. The document for View specifies why setTop, etc. should not be called outside the layout system. (See here.)

setTop

void setTop (int top)

Sets the top position of this view relative to its parent. This method is meant to be called by the layout system and should not generally be called otherwise, because the property may be changed at any time by the layout.

@Override
protected void onCreate(Bundle savedInstanceState) {
    Button button;

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    button = (Button) findViewById(R.id.button);
    button2 = (Button) findViewById(R.id.button2);
    rootView = (RelativeLayout) findViewById(R.id.rootView);
    otherLayout = (RelativeLayout) findViewById(R.id.otherLayout);

    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            RelativeLayout.LayoutParams params;
            int top = button2.getTop();
            int left = button2.getLeft();

            ((ViewGroup) button2.getParent()).removeView(button2);
            params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT);
            params.setMargins(left, top, 0, 0);
            button2.setLayoutParams(params);
            rootView.addView(button2);
        }
    });
}