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Getting View's coordinates relative to the root layout

The Android API already provides a method to achieve that. Try this:

Rect offsetViewBounds = new Rect();
//returns the visible bounds
childView.getDrawingRect(offsetViewBounds);
// calculates the relative coordinates to the parent
parentViewGroup.offsetDescendantRectToMyCoords(childView, offsetViewBounds); 

int relativeTop = offsetViewBounds.top;
int relativeLeft = offsetViewBounds.left;

Here is the doc


This is one solution, though since APIs change over time and there may be other ways of doing it, make sure to check the other answers. One claims to be faster, and another claims to be easier.

private int getRelativeLeft(View myView) {
    if (myView.getParent() == myView.getRootView())
        return myView.getLeft();
    else
        return myView.getLeft() + getRelativeLeft((View) myView.getParent());
}

private int getRelativeTop(View myView) {
    if (myView.getParent() == myView.getRootView())
        return myView.getTop();
    else
        return myView.getTop() + getRelativeTop((View) myView.getParent());
}

Let me know if that works.

It should recursively just add the top and left positions from each parent container. You could also implement it with a Point if you wanted.


Please use view.getLocationOnScreen(int[] location); (see Javadocs). The answer is in the integer array (x = location[0] and y = location[1]).


View rootLayout = view.getRootView().findViewById(android.R.id.content);

int[] viewLocation = new int[2]; 
view.getLocationInWindow(viewLocation);

int[] rootLocation = new int[2];
rootLayout.getLocationInWindow(rootLocation);

int relativeLeft = viewLocation[0] - rootLocation[0];
int relativeTop  = viewLocation[1] - rootLocation[1];

First I get the root layout then calculate the coordinates difference with the view.
You can also use the getLocationOnScreen() instead of getLocationInWindow().


No need to calculate it manually.

Just use getGlobalVisibleRect like so:

Rect myViewRect = new Rect();
myView.getGlobalVisibleRect(myViewRect);
float x = myViewRect.left;
float y = myViewRect.top;

Also note that for the centre coordinates, rather than something like:

...
float two = (float) 2
float cx = myViewRect.left + myView.getWidth() / two;
float cy = myViewRect.top + myView.getHeight() / two;

You can just do:

float cx = myViewRect.exactCenterX();
float cy = myViewRect.exactCenterY();