CODEWITHSUNDEEP
androidgridviewdrag-and-drop
Martin C.
Martin C.

Reputation: 301

Android GridView reorder elements via Drag and Drop

I have a GridView in an application I am working on. I would like to be able to reorder the items in the GridView via drag-and-drop. I have found lots of help for ListViews but nothing on GridViews. I want to achieve behaviour like in this launcher app http://www.youtube.com/watch?v=u5LISE8BU_E&t=5m30s. Any ideas?

Upvotes: 30

Views: 39407

Answers (8)

Ebrahim Karam
Ebrahim Karam

Reputation: 961

Google recently released a few code labs a few months back. https://codelabs.developers.google.com/codelabs/android-training-adaptive-layouts/index.html?index=..%2F..%2Fandroid-training#0

You can check the solution to it here https://github.com/google-developer-training/android-fundamentals-apps-v2/tree/master/MaterialMe-Resource

They make grid layout with movable cards that can be dragged and dropped anywhere in the layout using the itemTouchHandler.

The more detailed code on how to do the drag and drop is here You need to look into the Task 3: Make your CardView swipeable, movable, and clickable section

Upvotes: 2

Cody Pinto
Cody Pinto

Reputation: 111

Here's a library from h6ah4i that takes advantage of the Recycler Views to offer a drag and drop gridview with reorder capabilities.

Upvotes: 0

Dmytro Boichenko
Dmytro Boichenko

Reputation: 5407

If you don't resolve this problem I will provide my code. But it works on Android 3.0 and above, because I use android drag-n-drop framework

grid = (GridView) findViewById(R.id.grid);
grid.setAdapter(new DragGridAdapter(items, getActivity()));

....

grid.setOnTouchListener(new View.OnTouchListener() {

        @Override
        public boolean onTouch(View v, MotionEvent event) {

            if (event.getAction() == MotionEvent.ACTION_DOWN) {
                GridView parent = (GridView) v;

                int x = (int) event.getX();
                int y = (int) event.getY();

                int position = parent.pointToPosition(x, y);
                if (position > AdapterView.INVALID_POSITION) {

                    int count = parent.getChildCount();
                    for (int i = 0; i < count; i++) {
                        View curr = parent.getChildAt(i);
                        curr.setOnDragListener(new View.OnDragListener() {

                            @Override
                            public boolean onDrag(View v, DragEvent event) {

                                boolean result = true;
                                int action = event.getAction();
                                switch (action) {
                                case DragEvent.ACTION_DRAG_STARTED:
                                    break;
                                case DragEvent.ACTION_DRAG_LOCATION:
                                    break;
                                case DragEvent.ACTION_DRAG_ENTERED:
                                    v.setBackgroundResource(R.drawable.shape_image_view_small_gallery_selected);
                                    break;
                                case DragEvent.ACTION_DRAG_EXITED:
                                    v.setBackgroundResource(R.drawable.shape_image_view_small_gallery_unselected);
                                    break;
                                case DragEvent.ACTION_DROP:
                                    if (event.getLocalState() == v) {
                                        result = false;
                                    } else {
                                        View droped = (View) event.getLocalState();
                                        GridItem dropItem = ((DragGridItemHolder) droped.getTag()).item;

                                        GridView parent = (GridView) droped.getParent();
                                        DragGridAdapter adapter = (DragGridAdapter) parent.getAdapter();
                                        List<GridItem> items = adapter.getItems();

                                        View target = v;
                                        GridItem targetItem = ((DragGridItemHolder) target.getTag()).item;
                                        int index = items.indexOf(targetItem);
                                        items.remove(dropItem);
                                        items.add(index, dropItem);
                                        adapter.notifyDataSetChanged();
                                    }
                                    break;
                                case DragEvent.ACTION_DRAG_ENDED:
                                    v.setBackgroundResource(R.drawable.shape_image_view_small_gallery_unselected);
                                    break;
                                default:
                                    result = false;
                                    break;
                                }
                                return result;
                            }
                        });
                    }

                    int relativePosition = position - parent.getFirstVisiblePosition();


                    View target = (View) parent.getChildAt(relativePosition);

                    DragGridItemHolder holder = (DragGridItemHolder) target.getTag();
                    GridItem currentItem = holder.item;
                    String text = currentItem.getFile().getAbsolutePath();

                    ClipData data = ClipData.newPlainText("DragData", text);
                    target.startDrag(data, new View.DragShadowBuilder(target), target, 0);
                }
            }
            return false;

and DragGridAdapter

public class DragGridAdapter extends BaseAdapter{
private Context context;
private List<GridItem> items;

public DragGridAdapter(List<GridItem> items, Context context){
    this.context = context;
    this.items = items;
}

@Override
public int getCount() {
    return items.size();
}

@Override
public Object getItem(int position) {
    return items.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    DragGridItemHolder holder;
    if (convertView == null) {
        holder = new DragGridItemHolder();

        ImageView img = new ImageView(context);
        holder.image = img;
        convertView = img;
        convertView.setTag(holder);
    } else {
        holder = (DragGridItemHolder) convertView.getTag();
    }
    holder.item = items.get(position);
    holder.image.setImageBitmap(items.get(position).getBitmap());
    return convertView;
}

public List<GridItem> getItems() {
    return items;
}

I hope it helps to you

Upvotes: 24

Alex Askerov
Alex Askerov

Reputation: 391

My version for drag and drop grid view https://github.com/askerov/DynamicGrid.
It's extends original GridView, supports drag and drop to reorder items, auto-scroll if drag out of screen. It's completely functional on 3.0+ api, but supports 2.2 and 2.3 with limitations (no animations).

Upvotes: 7

Andrei Buneyeu
Andrei Buneyeu

Reputation: 6680

Probably PagedDragDropGrid project is what you need: https://github.com/mrKlar/PagedDragDropGrid

It provides custom ViewGroup (similar to GridView) with feature of smooth reordering (exactly like in your video). Probably it'll require a bit of customizations, but it's worth.

Hope it'll help.

Upvotes: 0

ac19
ac19

Reputation: 11

Using the drag-n-drop framework, instead that cycling the childs and setting the draglistener, I use as a grid item layout container, a DragableLinearLayout that extends the LinearLayout and implements the onDragEvent(DragEvent) method.

So you can fill your grid with the adapter as usual and most of the drag and drop code is on the onDragEvent of DragableLinearLayout

public class DragableLinearLayout extends LinearLayout {


    public DragableLinearLayout(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);

    }

    public DragableLinearLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

    }

    public DragableLinearLayout(Context context) {
        super(context);

    }

    @Override
    public boolean onDragEvent(DragEvent event) {
        //in wich grid item am I?
        GridView parent = (GridView) getParent();
        Object item = parent.getAdapter().getItem(
                parent.getPositionForView(this));
            //if you need the database id of your item...
        Cursor cur = (Cursor) item;
        long l_id = cur.getLong(cur.getColumnIndex("youritemid"));

        switch (event.getAction()) {
        case DragEvent.ACTION_DRAG_STARTED:

            return true;
        case DragEvent.ACTION_DRAG_ENTERED:

            setBackgroundColor(Color.GREEN);
            invalidate();
            return true;
        case DragEvent.ACTION_DRAG_EXITED:
            setBackgroundColor(Color.WHITE);
            invalidate();
            return false;
        case DragEvent.ACTION_DROP:
ClipData cd = event.getClipData();
            long l_id_start = Long.valueOf(cd.getItemAt(0).getText()
                    .toString());
            //
            Toast.makeText(getContext(), "DROP FROM " + l_id_start
                    + " TO " + l_id, Toast.LENGTH_LONG);
            //do your stuff  
                    ........
                    //the db requery will be on the onDragEvent.drop of the container
                    //see the listener


            return false;
        case DragEvent.ACTION_DRAG_ENDED:
            setBackgroundColor(Color.WHITE);
            invalidate();
            //
            return false;

        }

        return true;

    }


}



private View.OnDragListener listenerOnDragEvent = new View.OnDragListener() {

    public boolean onDrag(View v, DragEvent event) {
        // Defines a variable to store the action type for the incoming
        // event
        final int action = event.getAction();
        switch (action) {

        case DragEvent.ACTION_DROP:

            // REQUERY
            updateDbView();
            return false;
            // break;

        }
        return true;
    }
};

Upvotes: 1

vin
vin

Reputation: 337

Have a look at thquinn's DraggableGridView, This was developed targeting Android 2.2 (API level 8). Hope this helps someone :)

Upvotes: 2

jJ&#39;
jJ&#39;

Reputation: 3078

I recently found a solution on which its author spent quite some time here http://blahti.wordpress.com/2012/03/03/improved-drag-drop-for-gridview/ There are 4 previous related blog posts explaining what is going on in more detail there.

Upvotes: 0

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