【移动应用开发技术】怎么在Android中利用ListView实现一个侧滑删除功能

【移动应用开发技术】怎么在Android中利用ListView实现一个侧滑删除功能

本篇文章给大家分享的是有关怎么在Android中利用ListView实现一个侧滑删除功能，在下觉得挺实用的，因此分享给大家学习，希望大家阅读完这篇文章后可以有所收获，话不多说，跟着在下一起来看看吧。需求：1、listView可以侧滑item，展示删除按钮，点击删除按钮，删除当前的item2、在删除按钮展示时，点击隐藏删除按钮，不响应item的点击事件3、在删除按钮隐藏时，点击item响应点击事件根据以上需求在网络上查找响应的例子，也有仿QQ侧滑代码，但不能满足2和3的要求，因此修改了一把，代码如下，共大家拍砖第一步：重写ListViewpublic

class

SwipeListView

extends

ListView

{

private

final

static

String

TAG

=

"SwipeListView";

private

int

mScreenWidth;

//

屏幕宽度

private

int

mDownX;

//

按下点的x值

private

int

mDownY;

//

按下点的y值

private

int

mDeleteBtnWidth;//

删除按钮的宽度

private

boolean

isDeleteShown

=

false;

//

删除按钮是否正在显示

private

boolean

isOnClick

=

false;

private

ViewGroup

mPointChild;

//

当前处理的item

private

LinearLayout.LayoutParams

mLayoutParams;

//

当前处理的item的LayoutParams

public

SwipeListView(Context

context,

AttributeSet

attrs)

{

this(context,

attrs,

0);

}

public

SwipeListView(Context

context,

AttributeSet

attrs,

int

defStyle)

{

super(context,

attrs,

defStyle);

//

获取屏幕宽度

WindowManager

wm

=

(WindowManager)

context.getSystemService(Context.WINDOW_SERVICE);

DisplayMetrics

dm

=

new

DisplayMetrics();

wm.getDefaultDisplay().getMetrics(dm);

mScreenWidth

=

dm.widthPixels;

}

@Override

public

boolean

onTouchEvent(MotionEvent

ev)

{

switch

(ev.getAction())

{

case

MotionEvent.ACTION_DOWN:

performActionDown(ev);

break;

case

MotionEvent.ACTION_MOVE:

return

performActionMove(ev);

case

MotionEvent.ACTION_UP:

return

performActionUp(ev);

//

break;

}

return

super.onTouchEvent(ev);

}

//

处理action_down事件

private

void

performActionDown(MotionEvent

ev)

{

//

Log.e(TAG,"performActionDown===="+isDeleteShown);

if

(isDeleteShown)

{

turnToNormal();

}

isOnClick

=

true;

mDownX

=

(int)

ev.getX();

mDownY

=

(int)

ev.getY();

//

获取当前点的item

int

downPosition

=

pointToPosition(mDownX,

mDownY);

int

firstPosition=

getFirstVisiblePosition();

Log.e(TAG,"performActionDown====downPosition:"+downPosition+"==firstPosition"+firstPosition);

if(downPosition

<

0)

return;

mPointChild

=

(ViewGroup)

getChildAt(downPosition-firstPosition);

//

获取删除按钮的宽度

mDeleteBtnWidth

=

mPointChild.getChildAt(1).getLayoutParams().width;

mLayoutParams

=

(LinearLayout.LayoutParams)

mPointChild.getChildAt(0)

.getLayoutParams();

//

为什么要重新设置layout_width

等于屏幕宽度

//

因为match_parent时，不管你怎么滑，都不会显示删除按钮

//

why？

因为match_parent时，ViewGroup就不去布局剩下的view

mLayoutParams.width

=

mScreenWidth;

mPointChild.getChildAt(0).setLayoutParams(mLayoutParams);

}

//

处理action_move事件

private

boolean

performActionMove(MotionEvent

ev)

{

//

Log.e(TAG,

"performActionMove===="

+

isDeleteShown);

int

nowX

=

(int)

ev.getX();

int

nowY

=

(int)

ev.getY();

isOnClick

=

false;

if

(Math.abs(nowX

-

mDownX)

>

Math.abs(nowY

-

mDownY))

{

//

如果向左滑动

if

(nowX

<

mDownX)

{

//

计算要偏移的距离

int

scroll

=

(nowX

-

mDownX)

/

2;

//

如果大于了删除按钮的宽度，

则最大为删除按钮的宽度

if

(-scroll

>=

mDeleteBtnWidth)

{

scroll

=

-mDeleteBtnWidth;

}

//

重新设置leftMargin

mLayoutParams.leftMargin

=

scroll;

mPointChild.getChildAt(0).setLayoutParams(mLayoutParams);

}

return

true;

}

return

super.onTouchEvent(ev);

}

//

处理action_up事件

private

boolean

performActionUp(MotionEvent

ev)

{

boolean

falg

=

false;

if(isOnClick

&&

!isDeleteShown)

{

falg

=

true;

}

//

偏移量大于button的一半，则显示button

//

否则恢复默认

if

(-mLayoutParams.leftMargin

>=

mDeleteBtnWidth

/

2)

{

mLayoutParams.leftMargin

=

-mDeleteBtnWidth;

isDeleteShown

=

true;

}

else

{

turnToNormal();

isDeleteShown

=

false;

}

mPointChild.getChildAt(0).setLayoutParams(mLayoutParams);

//

Log.e(TAG,

"performActionUp===="

+

isDeleteShown);

if(falg)

{

return

super.onTouchEvent(ev);

}

return

true;

}

/**

*

变为正常状态

*/

public

void

turnToNormal()

{

mLayoutParams.leftMargin

=

0;

mPointChild.getChildAt(0).setLayoutParams(mLayoutParams);

}

/**

*

当前是否可点击

*

*

@return

是否可点击

*/

public

boolean

canClick()

{

return

!isDeleteShown;

}

}第二步：适配器class

SwipeListAdapter

extends

BaseAdapter

{

@Override

public

int

getCount()

{

return

mData.size();

}

@Override

public

Object

getItem(int

position)

{

return

mData.get(position);

}

@Override

public

long

getItemId(int

position)

{

return

position;

}

@Override

public

View

getView(int

position,

View

convertView,

ViewGroup

parent)

{

ViewHolder

holder

=

null;

if

(null

==

convertView)

{

holder

=

new

ViewHolder();

convertView

=

View.inflate(TestListViewActivity.this,

R.layout.item_swipe_list,

null);

holder.tv

=

(LinearLayout)

convertView.findViewById(R.id.tv);

holder.tvName

=

(TextView)

convertView.findViewById(R.id.tv_name);

holder.delete

=

(TextView)

convertView.findViewById(R.id.delete);

convertView.setTag(holder);

}

else

{

holder

=

(ViewHolder)

convertView.getTag();

}

holder.tvName.setText(mData.get(position));

final

int

pos

=

position;

holder.delete.setOnClickListener(new

View.OnClickListener()

{

@Override

public

void

onClick(View

v)

{

mData.remove(pos);

notifyDataSetChanged();

mListView.turnToNormal();

}

});

return

convertView;

}

}

static

class

ViewHolder

{

LinearLayout

tv;

TextView

tvName;

TextView

delete;

}第三步：写一个TestListViewActivityprivate

SwipeListView

mListView;

private

ArrayList<String>

mData

=

new

ArrayList<String>()

{

{

for

(int

i

=

0;

i

<

20;

i++)

{

add("hello

world,

hello

android

"

+

i);

}

}

};

@Override

protected

void

onCreate(Bundle

savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_test_list_view);

Toolbar

toolbar

=

(Toolbar)

findViewById(R.id.toolbar);

setSupportActionBar(toolbar);

FloatingActionButton

fab

=

(FloatingActionButton)

findViewById(R.id.fab);

fab.setOnClickListener(new

View.OnClickListener()

{

@Override

public

void

onClick(View

view)

{

Snackbar.make(view,

"Replace

with

your

own

action",

Snackbar.LENGTH_LONG)

.setAction("Action",

null).show();

}

});

mListView

=

(SwipeListView)

findViewById(R.id.list);

mListView.setAdapter(new

SwipeListAdapter());

//

mListView.setOnItemLongClickListener(new

AdapterView.OnItemLongClickListener()

{

//

@Override

//

public

boolean

onItemLongClick(AdapterView<?>

parent,

View

view,

int

position,

long

id)

{

//

Toast.makeText(TestListViewActivity.this,

mData.get(position)

+

"被点击了",

//

Toast.LENGTH_SHORT).show();

//

return

false;

//

}

//

});

mListView.setOnItemClickListener(new

AdapterView.OnItemClickListener()

{

@Override

public

void

onItemClick(AdapterView<?>

parent,

View

view,

int

position,

long

id)

{

Log.e("SwipeListView",

"setOnItemClickListener===="

+

mListView.canClick());

//

Toast.makeText(TestListViewActivity.this,

mData.get(position)

+

"被点击了",

//

Toast.LENGTH_SHORT).show();

}

});

}第四步：布局文件<?xml

version="1.0"

encoding="utf-8"?>

<RelativeLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

xmlns:app="/apk/res-auto"

android:layout_width="match_parent"

android:layout_height="match_parent"

app:layout_behavior="@string/appbar_scrolling_view_behavior"

tools:showIn="@layout/activity_test_list_view"

tools:context="com.kimascend.ledappd1.activity.TestListViewActivity">

<com.kimascend.ledappd1.view.SwipeListView

android:id="@+id/list"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:cacheColorHint="@android:color/transparent"

android:listSelector="@android:color/transparent"

android:divider="@android:color/darker_gray"

android:dividerHeight="2dp">

</com.kimascend.ledappd1.view.SwipeListView>

</RelativeLayout>第五步：item的布局文件<?xml

version="1.0"

encoding="utf-8"?>

<LinearLayout

xmlns:android="/apk/res/android"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:orientation="horizontal">

<LinearLayout

android:id="@+id/tv"

android:orientation="horizontal"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:background="@android:color/white"

android:paddingBottom="20dp"

android:paddingL