Android Drag-n-Drop grid with LinearLayouts as drag items

Question

I have a working example of a grid that allows items to be reordered using long touches to active a drag-n-drop. All is working well if the items are simple Views e.g. TextView or ImageView but if the items are LinearLayouts only the layout itself is displayed.

I've been using Tom Quinsn's grid (thanks Tom!!!) from this posting:

Android Gridview drag and drop example

I can get LinearLayouts to work if I derive my own LinearLayout class and override onLayout(), but this forces me to hardcode the positions of the child controls in the layout within this function.

Ideally I would like to be able to define the item layout within an XML file and inflate them before adding them to the Control that handles the grid. I'm guessing that for some reason the framework is not calling the layout function for the children contained within the DraggableGridView view as defined in Tom's code but I can't understand why that is.

Answer 1

I am developing my own Drag and Drop app with good help from this link. You may compare the code with the one from Tom Quesinsn. It also gets the different children of a GridView and add them as "drop targets" that accepts drops on them and copy the Image of the View you are dragging.

Answer 2

This is a known problem with the DraggableGridView that -- unfortunately -- I haven't gotten around to fixing. When I wrote DGV, I didn't entirely grasp how views were laid out. You might try having DGV measure each child before laying it out. Adding something like:

getChildAt(i).measure(MeasureSpec.makeMeasureSpec(childSize, MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(childSize, MeasureSpec.EXACTLY));

before the layout on this line:

getChildAt(i).layout(xy.x, xy.y, xy.x + childSize, xy.y + childSize);