关于ListView的问题

listview的子项不能一直删除，当然删除到只有7项的时候就会报数组溢出的问题。

求解答！以下是代码

packagecom.example.ex_listview;

importjava.util.arraylist;

importandroid.os.bundle;

importandroid.app.activity;

importandroid.view.menu;

importandroid.view.view;

importandroid.view.view.onclicklistener;

importandroid.view.viewgroup;

importandroid.widget.baseadapter;

importandroid.widget.button;

importandroid.widget.imageview;

importandroid.widget.listview;

importandroid.widget.relativelayout;

importandroid.widget.textview;

publicclassmainactivityextendsactivityimplementsonclicklistener{

int[]imgs=newint[]{r.drawable.cup,r.drawable.date,

r.drawable.drawer,r.drawable.folder,r.drawable.gear,

r.drawable.globe,r.drawable.heart,r.drawable.help,

r.drawable.inbox,r.drawable.info,r.drawable.leaf,

r.drawable.lock,r.drawable.mail,r.drawable.moleskine,

r.drawable.monitor,r.drawable.music,r.drawable.notebook,

r.drawable.pill,r.drawable.present,r.drawable.print};

arraylist<dataencap>list=newarraylist<dataencap>();

privatemybaseadaptermba;

@override

protectedvoidoncreate(bundlesavedinstancestate){

super.oncreate(savedinstancestate);

setcontentview(r.layout.activity_main);

settitle("消息");

buttonbtndelete=(button)findviewbyid(r.id.button1);

buttonbtnadd=(button)findviewbyid(r.id.button2);

btndelete.setonclicklistener(this);

btnadd.setonclicklistener(this);

listviewlistview=(listview)findviewbyid(r.id.listview1);

mba=newmybaseadapter();

listview.setadapter(mba);

for(inti=0;i<imgs.length;i++){

dataencapdata=newdataencap(imgs[i],"昵称"+i,"已聊过的消息内容"+i,"20:"+i);

list.add(data);

}

publicvoiddelete(){

if(list.size()>0){

list.remove(0);

mba.notifydatasetchanged();

publicvoidadd(dataencapdata){

classmybaseadapterextendsbaseadapter{

publicintgetcount(){

returnimgs.length;

publicviewgetview(intposition,viewconvertview,viewgrouparg2){

relativelayoutlayout=null;

viewholderholder=null;

if(convertview==null){

layout=(relativelayout)getlayoutinflater().inflate(r.layout.listview_item,null);

holder=newviewholder();

holder.p_w_picpath=(imageview)layout.findviewbyid(r.id.p_w_picpathview1);

holder.tv_name=(textview)layout.findviewbyid(r.id.textview1);

holder.tv_text=(textview)layout.findviewbyid(r.id.textview2);

holder.tv_time=(textview)layout.findviewbyid(r.id.textview3);

layout.settag(holder);

}else{

layout=(relativelayout)convertview;

holder=(viewholder)layout.gettag();

dataencapdata=list.get(position);

holder.p_w_picpath.setimageresource(data.img);

holder.tv_text.settext(data.text);

holder.tv_name.settext(data.name);

holder.tv_time.settext(data.time);

returnlayout;

publicobjectgetitem(intposition){

returnnull;

publiclonggetitemid(intposition){

return0;

classdataencap{

intimg;

stringname;

stringtext;

stringtime;

publicdataencap(intimg,stringname,stringtext,stringtime){

this.img=img;

this.name=name;

this.text=text;

this.time=time;

classviewholder{

imageviewp_w_picpath;

textviewtv_name;

textviewtv_text;

textviewtv_time;

publicbooleanoncreateoptionsmenu(menumenu){

getmenuinflater().inflate(r.menu.main,menu);

returntrue;

publicvoidonclick(viewv){

switch(v.getid()){

caser.id.button1:

delete();

break;

caser.id.button2:

dataencapdata=newdataencap(r.drawable.ic_launcher,"昵称","已聊过的消息内容","20:20");

add(data);

default: