Android开发ListView中含有checkBox或者Button时会遇到的难题

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android开发经常会遇到ListView中含有checkBox和Button的情况，这里主要会有三个问题，下面分别论述：

1. ListView中含有checkBox或者Button时，listView的item无法响应点击事件，这主要是因为checkBox和Button等获取焦点的能力高于listView，此时应该让其子控件不能获取焦点，即在布局文件中设置子控件属性android:focusable="false"或者在listView的adapter的布局中加入android:descendantFocusability="blocksDescendants"属性，descendantFocusability表示子控件均失去焦点。

2. ListView中含有checkBox时，选中CheckBox时，滑动listView会发现有多个选中的checkBox,即发生了错位，这个主要是与adapter的getView方法的机制有关系，即listView的每个界面都显示固定的item数，当滑动时，只是将前一屏的item重新绘制了一遍，这个可以先去了解下自定义adpter的getView的刷新机制。对于这个问题的解决办法是记录下选中的checkBox的位置（这个方法是当点击ListView的item时选中checkBox的前提），在getView中根据选中位置进行设置checkBox的状态。

注意：主要是在adapter中保存一个hashset保存对象，然后checkbox的setcheck（）方法要放在checkbox的onitemcheckedchang()监听方法之后，否是会先设置checkbox的状态而发生选中错位。

具体代码见下面：

public class ScheduleItemsAdapter extends BaseAdapter {

private List<ScheduleItem> scheduleItems;
private LayoutInflater inflater;
private Context ctx;
private Callback callBack ;
private boolean onlineFlag = false ;

private Set<ScheduleItem> checkeds = new HashSet<ScheduleItem>();

boolean showAddressFlag = false;
public interface Callback {
public void callbackCheckbox(boolean isChecked , int position);
public void callbackItems(int position);
public void callbackOnOff(boolean isChecked , int position);
public void callbackColor(int position);
public void callackTimes(int position );
}

public ScheduleItemsAdapter(Context context, List<ScheduleItem> ScheduleItem , boolean onlineFlag) {
this.ctx = context;
this.onlineFlag = onlineFlag;
this.scheduleItems = new ArrayList<ScheduleItem>();
this.scheduleItems.clear();
if (scheduleItems != null)
this.scheduleItems.addAll(scheduleItems);
inflater = LayoutInflater.from(context);

}

public void setCallBack(Callback callBack ){
this.callBack = callBack ;
}

public void notificationLightListChange(List<ScheduleItem> ScheduleItem) {
this.scheduleItems.clear();
if (ScheduleItem != null) {
this.scheduleItems.addAll(ScheduleItem);
}
checkeds.clear();
notifyDataSetChanged();
}

public List<ScheduleItem> getCheckedList() {
List<ScheduleItem> list = new ArrayList<ScheduleItem>();
list.addAll(checkeds);
return list;
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return scheduleItems.size();
}

@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return scheduleItems.get(arg0);
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub

ContainerView listItemView = null;
final ScheduleItem item = scheduleItems.get(position);

if (convertView == null) {
convertView = inflater.inflate(R.layout.schedule_mode_item_listview, null);
listItemView = new ContainerView();
listItemView.checkbox = (CheckBox) convertView.findViewById(R.id.schedule_mode_listview_checkbox);
listItemView.sequence = (TextView) convertView.findViewById(R.id.schedule_mode_listview_sequence_number);
listItemView.itemName = (TextView)convertView.findViewById(R.id.schedule_mode_listview_item_name);
listItemView.interval = (TextView) convertView.findViewById(R.id.schedule_mode_listview_interval);
listItemView.changedata = (TextView) convertView.findViewById(R.id.schedule_mode_listview_changedata);
listItemView.color = (TextView) convertView.findViewById(R.id.schedule_mode_listview_color);
listItemView.action = (ToggleButton) convertView.findViewById(R.id.schedule_mode_listview_onoff);
convertView.setTag(listItemView);

} else {
listItemView = (ContainerView) convertView.getTag();
}

if(! onlineFlag)
{
listItemView.itemName .setVisibility(View.GONE);
}
if(item.getScheduleItemId() != -1){
switch (item.getscheduleItemType() ){
case ScheduleItem.scheduleItemType_Light:
listItemView.color .setVisibility(View.VISIBLE);
listItemView.itemName .setText(LightDAO.getDAO(ctx).findById(item.getScheduleItemId()).getName());
break;
case ScheduleItem.scheduleItemType_GROUP:
listItemView.color .setVisibility(View.VISIBLE);
listItemView.itemName .setText(GroupDAO.getDAO(ctx).findById(item.getScheduleItemId()).getName());
break;
case ScheduleItem.scheduleItemType_SCENE:
listItemView.color .setVisibility(View.INVISIBLE);
listItemView.itemName .setText(SceneDAO.getDAO(ctx).findById(item.getScheduleItemId()).getName());
break;

default:
break;
}
}else{
listItemView.itemName .setText("null");
}

listItemView.sequence.setText(position+1+"");

listItemView.color.setBackgroundColor(Color.rgb((item.getPwmR() & 0xff) *(item.getPwm() & 0xff) /255 , (item.getPwmG() & 0xff) *(item.getPwm() & 0xff) /255, (item.getPwmB() & 0xff) *(item.getPwm() & 0xff) /255));
if((int)item.getChangeData() < 10){
listItemView.changedata.setText("0."+(item.getChangeData() & 0xff ));
}else{
listItemView.changedata.setText((item.getChangeData() & 0xff )/10 + "");
}

if((int)item.getintervalTime() < 10){
listItemView.interval.setText("0."+(item.getintervalTime() & 0xff ));
}else{
listItemView.interval.setText(((item.getintervalTime() & 0xff ) )/10 + "");
}

listItemView.checkbox.setOnCheckedChangeListener(new OnCheckedChangeListener() {

@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callbackCheckbox(isChecked, position);
}
if (isChecked) {
checkeds.add(item);
} else {
checkeds.remove(item);
}
}
});

listItemView.interval.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callackTimes(position);
}
}
});

listItemView.changedata.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callackTimes(position);
}
}
});
listItemView.action.setOnCheckedChangeListener(new OnCheckedChangeListener() {

@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callbackOnOff(isChecked ,position);
}
}
});

//ToggleButton和checkbox等类的setchecked()方法要放在监听后面，避免误触发

listItemView.action.setChecked( item.getAction() ==ScheduleItem.ACTION_OFF ? false :true);
listItemView.color.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callbackColor(position);
}
}
});
listItemView.itemName.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (callBack != null) {
callBack.callbackItems(position);
}
}
});

return convertView;
}

static class ContainerView {
public CheckBox checkbox ;
public TextView sequence;
public TextView itemName;
public TextView interval;
public TextView changedata;
public ToggleButton action;
public TextView color;

}

}

3. ListView中含有Button时，我们有时需要知道点击button位于listView的哪个position下，即要获取item的数据，由于button的click事件是异步的，无法得到点击的位置，这个原因与上面的checkBox类似，这时有一个办法是给button设置Tag，点击时获取tag来判断位置，实现代码如下：

Android开发ListView中含有checkBox或者Button时会遇到的难题

注意：主要是在adapter中保存一个hashset保存对象，然后checkbox的setcheck（）方法要放在checkbox的onitemcheckedchang()监听方法之后，否是会先设置checkbox的状态而发生选中错位。

具体代码见下面：

@Override

public View getView(int position, ViewconvertView, ViewGroup parent) {

ListHolderholder;

if (convertView == null) {

holder =new ListHolder();

convertView= mInflater.inflate(R.layout.homework_list_item, null);

holder.homeworkUpload = (Button)convertView.findViewById(R.id.homework_list_btn_uploadhomework);

convertView.setTag(holder);

}else {

holder =(ListHolder) convertView.getTag();

}

holder.homeworkUpload.setTag(position);

holder.homeworkUpload.setOnClickListener(new OnClickListener(){

@Override

publicvoid onClick(View v) {

/**

* 上传家庭作业功能暂时屏蔽

*/

Log.i("hubei", "click position:"+v.getTag());

Object homework = list.get(Integer.parseInt(""+v.getTag()));

}

});

}

return convertView;

}