我正在从php url获取一些数据,并显示自定义ListView上的数据。在"类别"listView中,用户将选择一个类别复选框,并进一步根据所选项目,我正在从另一个url发送该项目的id以获取"子类别",我正在显示另一个listView中的子类别项目。但问题是,每当我点击另一个复选框的子类别项目由新获取的项目取代。我想显示与选定的"类别"复选框对应的所有子类别…求你了,求你帮帮我,我该怎么做?这里是onClickListener的"类别"复选框。
holder.name.setOnClickListener( new View.OnClickListener() {
public void onClick(View v) {
CheckBox cb = (CheckBox) v ;
Category Category = (Category) cb.getTag();
/*Toast.makeText(getApplicationContext(),"Clicked on Checkbox: " + cb.getText() +" is " + cb.isChecked(),
Toast.LENGTH_LONG).show();*/
category_id=cb.getText().toString();
receiveSubCategory();
Category.setSelected(cb.isChecked());
}
});
这是我如何获得值。private void receiveSubCategory(){
StringRequest stringRequest = new StringRequest(Request.Method.POST,Sub_Cate_URL,new Response.Listener<String>() {
@Override
public void onResponse(String response) {
//Log.d("sub response", response);
receiveSubJSOn(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
String er=error.getMessage();
Toast.makeText(UpdateUserProfile.this,er,Toast.LENGTH_LONG).show();
//Log.d("","error message"+er);
}
}){
@Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("category_id",category_id);
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void receiveSubJSOn(String json){
ParseJSON pj = new ParseJSON(json);
pj.receiveSubCategory();
sub_category_id=ParseJSON.sub_id;
sub_cate_name=ParseJSON.sub_name;
displaySubCategory();
这是我如何在listView上显示项目:private void displaySubCategory() {
//Array list of categories
ArrayList<SubCategory> CategoryList = new ArrayList<SubCategory>();
//sub_category_id=temp_id;
//sub_cate_name=temp_name;
for(int i=0;i<sub_cate_name.length;i++) {
SubCategory Category = new SubCategory(sub_cate_name[i], sub_category_id[i], false);
CategoryList.add(Category);
}
//create an ArrayAdaptar from the String Array
subCategory = new SubCategoryAdapter(this,R.layout.sub_category_items, CategoryList);
ListView listView = (ListView) findViewById(R.id.sub_category_list);
// Assign adapter to ListView
listView.setAdapter(subCategory);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
Category Category = (Category) parent.getItemAtPosition(position);
Toast.makeText(getApplicationContext(),
"Clicked on Row: " + Category.getName(),
Toast.LENGTH_LONG).show();
}
});
}
这是我的适配器类私有类SubCategoryAdapter扩展ArrayAdapter {
private ArrayList<SubCategory> CategoryList;
private String[] ids;
public SubCategoryAdapter(Context context, int textViewResourceId,ArrayList<SubCategory> CategoryList) {
super(context, textViewResourceId, CategoryList);
this.CategoryList = new ArrayList<SubCategory>();
this.CategoryList.addAll(CategoryList);
// ids=id;
}
private class ViewHolder {
TextView code;
CheckBox name;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
//Log.v("ConvertView", String.valueOf(position));
if (convertView == null) {
LayoutInflater vi = (LayoutInflater)getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
convertView = vi.inflate(R.layout.sub_category_items, null);
holder = new ViewHolder();
holder.code = (TextView) convertView.findViewById(R.id.sub_list_text);
holder.name = (CheckBox) convertView.findViewById(R.id.sub_category_checkbox);
convertView.setTag(holder);
holder.name.setOnClickListener( new View.OnClickListener() {
public void onClick(View v) {
CheckBox cb = (CheckBox) v ;
SubCategory Category = (SubCategory) cb.getTag();
/* Toast.makeText(getApplicationContext(),
"Clicked on Checkbox: " + cb.getText() +
" is " + cb.isChecked()Toast.LENGTH_LONG).show();*/
Category.setSelected(cb.isChecked());
}
});
}
else {
holder = (ViewHolder) convertView.getTag();
}
SubCategory Category = CategoryList.get(position);
holder.code.setText(""+Category.getCode()+"");
holder.name.setText(Category.getName());
holder.name.setChecked(Category.isSelected());
holder.name.setTag(Category);
return convertView;
}
}
下面是输出:复选框图片
试试这个:-
步骤1:在方法"displaySubCategory"中,从该方法中删除行"ArrayList CategoryList = new ArrayList();",并在该页面上全局添加相同的行。这会解决你的问题。但是为适配器创建多个实例并不是正确的方法。所以也要遵循第二步。
步骤2:在方法"displaySubCategory"中,您正在为SubCategoryAdapter创建新的实例"subCategory = new SubCategoryAdapter(this, r.b layout.)"。sub_category_items CategoryList);"
你应该只在一个页面中为适配器"SubCategoryAdapter"创建一次实例。
删除subCategory = new SubCategoryAdapter(this,R.layout. adapter)sub_category_items, CategoryList);"来自"displaySubCategory"方法。并在onCreateView/onCreate事件中添加相同的行。
在"displaySubCategory"方法中添加这行"subCategory.notifyDataSetChanged();"