DragSortExpandiableListView

I had customize this DragSortExpandiableListView refer to this https://github.com/bauerca/drag-sort-listview to make android default Expandible ListView can perform drag and drop. Thanks to this repo author @bauerca

Overview

DragSortExpandiableListView (DSLV) is an extension of the Android ExpandiableListView that enables drag-and-drop reordering of list group items only. It is a major overhaul complete rewrite of the TouchInterceptor (TI) meant to give drag-sorting a polished feel. Some key features are:

1. drag and drop
2. Intuitive and smooth scrolling while dragging.
3. Support for heterogeneous item heights.
4. Public startDrag() and stopDrag() methods.
5. Public interface for customizing the floating View.

I hope you find it useful; and please, help me improve the thing!

Widget usage

Three major elements define the drag-sort process. Roughly, in order of importance, they are:

1. Data reordering. Drag-sorts reorder the data underlying your list. Since DSLV cannot know how you organize your data, the reordering must be performed by you using the provided Listener interfaces.
2. Drag start/stop. Drags are started and stopped by calling startDrag() and stopDrag() on your DSLV instance; but some help that is. The convenience class, DragSortController, provides all kinds of boiler-plate for common start/stop/remove drag patterns.
3. Floating View. The floating View appearance and behavior is controlled by an implementation of the FloatViewManager interface. With this, you can display any View you like as the floating View, and update its appearance/location on every touch event. The DragSortController helper class also implements this interface for convenience.

Number 1 is essential. As mentioned above, 2 and 3 can be handled by the DragSortController helper class. Keep reading, then head to the demo and start studying some examples.

you also may refer to the demo how DragSortExpandibleListView is implemented

XML attributes

• collapsed_height: (dimension, 1px) Height of placeholder at original drag position. Cannot be zero.
• drag_scroll_start: (float, 0.3) Start of drag-scroll regions (defined by a fraction of the total DSLV height; i.e. between 0 and 1).
• max_drag_scroll_speed: (float, 0.5) Maximum drag-scroll speed for default linear drag-scroll profile. Units of pixels/millisecond.
• float_alpha: (float, 1.0) Transparency of floating View. Value from 0 to 1 where 1 is opaque.
• slide_shuffle_speed: (float, 0.7) Speed of shuffle animations underneath floating View. A value of 0 means a shuffle animation is always in progress, whereas a value of 1 means items snap from position to position without animation.
• drop_animation_duration: (int, 150) Drop animation smoothly centers the floating View over the drop slot before destroying it. Duration in milliseconds.
• remove_animation_duration: (int, 150) Remove animation smoothly collapses the empty slot when an item is removed. Duration in milliseconds.
• track_drag_sort: (bool, false) Debugging option; explained below.
• use_default_controller: (bool, true) Have DSLV create a DragSortController instance and pass the following xml attributes to it. If you set this to false, ignore the following attributes.
• float_background_color: (color, BLACK) Set the background color of the floating View when using the default DragSortController. Floating View in this case is a snapshot of the list item to be dragged.
• drag_handle_id: (id, 0) Android resource id that points to a child View of a list item (or the root View of the list item layout). This identifies the "drag handle," or the View within a list item that must be touched to start a drag-sort of that item. Required if drags are to be enabled using the default DragSortController.
• sort_enabled: (bool, true) Enable sorting of dragged item (disabling is useful when you only want item removal).
• drag_start_mode: (enum, "onDown") Sets the gesture for starting a drag.
  • "onDown": Drag starts when finger touches down on the drag handle.
  • "onDrag": Drag starts when finger touches down on drag handle and then drags (allows item clicks and long clicks).
  • "onLongPress": Drag starts on drag handle long press (allows item clicks).
• remove_enabled: (bool, false) Enable dragged item removal by one of the remove_mode options below.
• remove_mode: (enum, "flingRight") Sets the gesture for removing the dragged item.
  • "clickRemove": Click on item child View with id click_remove_id.
  • "flingRemove": Fling horizontal anywhere on item.
• click_remove_id: (id, 0) Android resource id that points to a child View of a list item. When remove_mode="clickRemove" and remove_enabled="true", a click on this child View removes the containing item. This attr is used by DragSortController.
• fling_handle_id: (id, 0) Android resource id that points to a child View of a list item. When remove_mode="flingRemove" and remove_enabled="true", a fling that originates on this child View removes the containing item. This attr is used by DragSortController.

Contributing

First of all, thank you! Many of your pull requests have added tremendous value to this project. Your efforts are truly appreciated!

Now that the project is fairly mature, I would like to lay out some (loose) rules for future pull requests. So far I have only one (of course, you should help me add more). Here's the list:

• Avoid pull requests that are small tweaks to default DragSortController behavior. This class is merely a guide/helper for creating more complex drag-sort interactions. For example, if you don't like the feel of the default fling-remove initiation for your app, then you should not create a pull request that "fixes" the behavior. Rather, try to modify or subclass DragSortController for your particular needs. That said, if a "must-have" touch pattern arises, I think there is some wiggle room in this rule.

License

A subclass of the Android ListView component that enables drag
and drop re-ordering of list items.

Copyright 2012 Carl Bauer

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.