Select and delete multiple items in a list in Sketchware android project

1. In image manager of project, add delete icon ic_delete_white.

2. In Resource, in menu folder, add an xml file named context_menu.xml. Put following code in this file:


<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/delete"
        android:title="Delete"
        android:icon="@drawable/ic_delete_white"
        android:showAsAction="always"/>
</menu>

3. Create a new custom variable of type SparseBooleanArray with name selectedItems and define it as new SparseBooleanArray().


4. Put following codes in onCreate. Change names of variables as in your project.


// Enable multiple selection mode with contextual action bar
listview1.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE_MODAL);

// Handle selection events via MultiChoiceModeListener
listview1.setMultiChoiceModeListener(new AbsListView.MultiChoiceModeListener() {

    @Override
    public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) {
        // Update the selection map based on user interaction
        if (checked) {
            selectedItems.put(position, true); // Mark item as selected
        } else {
            selectedItems.delete(position);    // Unmark item
        }

        // Refresh the adapter to visually highlight selected items
        ((BaseAdapter)listview1.getAdapter()).notifyDataSetChanged();

        // Update the ActionMode title with the number of selected items
        mode.setTitle(selectedItems.size() + " selected");
    }

    @Override
    public boolean onCreateActionMode(ActionMode mode, Menu menu) {
        // Inflate the contextual menu (e.g., delete option)
        getMenuInflater().inflate(R.menu.context_menu, menu);
        return true;
    }

    @Override
    public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
        // Handle clicks on contextual menu items
        if (item.getItemId() == R.id.delete) {
            // Loop backwards to safely remove selected items
            for (int i = listview1.getCount() - 1; i >= 0; i--) {
                if (selectedItems.get(i)) {
                    maplist.remove(i); // Remove item from data list
                }
            }

            // Clear selection and update UI
            selectedItems.clear();
            ((BaseAdapter)listview1.getAdapter()).notifyDataSetChanged();

            // Save updated list to SharedPreferences as JSON
            sp.edit().putString("data", new Gson().toJson(maplist)).commit();

            // Close action mode
            mode.finish();
            return true;
        }
        return false;
    }

    @Override
    public void onDestroyActionMode(ActionMode mode) {
        // Clear selection and refresh UI when action mode ends
        selectedItems.clear();
        ((BaseAdapter)listview1.getAdapter()).notifyDataSetChanged();
    }

    @Override
    public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
        // Not used here, return false
        return false;
    }
});

5. In onBindCustomView, if selectedItems.get(_position, false), change background colour of outermost linear in custom view.

6. Save and run the project.




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