android – 单击按钮在列表项的textview中设置文本
作者：互联网
我创建了一个列表视图,如下图所示.链接：
问题：我希望如果用户点击按钮或 – 当前显示0的文本视图相应地递增或递减.但是,如果我单击第一个项目的按钮,则会在其他行中更新textview.我不知道如何实现这一点.
这是代码：
public class HomePage extends Fragment {
String[] listitems;
int[] images = { R.drawable.cadburysilk, R.drawable.cadburys_dairymilk,
R.drawable.perk, R.drawable.kitkat,
R.drawable.nestlemunchchocolate, R.drawable.cadbury_bournville_bar,
R.drawable.snickers };
ListView list;
DBAdapter dbadapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View rootview = inflater.inflate(R.layout.activity_home_page,
container, false);
View view = View.inflate(getActivity(), R.layout.headerview, null);
Resources res = getResources();
listitems = res.getStringArray(R.array.items);
list = (ListView) rootview.findViewById(R.id.itemslist);
list.addHeaderView(view);
AdapterClass adapterClass = new AdapterClass(this.getActivity(),
listitems, images);
list.setAdapter(adapterClass);
return rootview;
}
}
class AdapterClass extends ArrayAdapter<String> {
Context context;
int[] images;
String[] names;
Button add, sub;
TextView number;
Integer count=0;
static class ViewHolder {
public TextView textView;
public ImageView imageView;
}
public AdapterClass(Context c, String[] items, int imgs[]) {
// TODO Auto-generated constructor stub
super(c, R.layout.rowlayout, R.id.quantity, items);
this.context = c;
this.images = imgs;
this.names = items;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
View row = convertView;
// reuse views
if (row == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.rowlayout, parent, false);
ViewHolder viewHolder = new ViewHolder();
viewHolder.imageView = (ImageView) row.findViewById(R.id.img);
viewHolder.textView = (TextView) row.findViewById(R.id.textView1);
add = (Button) row.findViewById(R.id.button1);
add.setTag(position);
sub = (Button) row.findViewById(R.id.button2);
sub.setTag(position);
number = (TextView)row.findViewById(R.id.quantity);
row.setTag(viewHolder);
}
ViewHolder holder = (ViewHolder) row.getTag();
holder.imageView.setImageResource(images[position]);
holder.textView.setText(names[position]);
add.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
count=count+1;
number.setText(count.toString());
}
});
sub.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
count=count-1;
number.setText(count.toString());
}
});
return row;
}
}
请帮忙.此外,我需要帮助如何显示textview包含下一个活动或片段中的正数的项目.
解决方法:
按照用户370305的回答进行初始查询.
Please help. Also i need help in how to show the items whose textview contains positive number in next activity or fragment.
创建一个数据结构,我正在使用HashMap,其中key是String.valueOf(position),Value是count int.
你知道密钥,因为它将从位置“0”到listitem.length.使用密钥,您可以获取计数值并检查正数.
为什么选择Hashmap：因为每次更改计数时,新值都将被覆盖. (在hashmap中只维护一个唯一键).
(position = 0,count = 0) – > – 点击第0行 – > (位置0,计数= -1)将在key = 0单元格上重写.
完整代码(具有数字增量修复并在DataStructure中具有一组正值)：
public class HomePage extends Fragment {
String[] listitems;
int[] images = { R.drawable.cadburysilk, R.drawable.cadburys_dairymilk,
R.drawable.perk, R.drawable.kitkat,
R.drawable.nestlemunchchocolate, R.drawable.cadbury_bournville_bar,
R.drawable.snickers };
ListView list;
DBAdapter dbadapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View rootview = inflater.inflate(R.layout.activity_home_page,
container, false);
View view = View.inflate(getActivity(), R.layout.headerview, null);
Resources res = getResources();
listitems = res.getStringArray(R.array.items);
list = (ListView) rootview.findViewById(R.id.itemslist);
list.addHeaderView(view);
AdapterClass adapterClass = new AdapterClass(this.getActivity(),
listitems, images);
list.setAdapter(adapterClass);
return rootview;
//You can use adapterClass.getPositiveNumber(); to retrieve all positive rows and the values!
//Unique key will be String : 1,2,3....listitems.length.
}
}
class AdapterClass extends ArrayAdapter<String> {
Context context;
int[] images;
String[] names;
Button add, sub;
ViewHolder holder; // Since will be accessed inside onclick
HashMap<String,Integers> positiveNumbers = new HashMap<String,Integers>;
Integer count=0;
static class ViewHolder {
public TextView textView;
public ImageView imageView;
public TextView number;
public String uniqueKey;
}
public AdapterClass(Context c, String[] items, int imgs[]) {
// TODO Auto-generated constructor stub
super(c, R.layout.rowlayout, R.id.quantity, items);
this.context = c;
this.images = imgs;
this.names = items;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
View row = convertView;
// reuse views
if (row == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.rowlayout, parent, false);
ViewHolder viewHolder = new ViewHolder();
viewHolder.imageView = (ImageView) row.findViewById(R.id.img);
viewHolder.textView = (TextView) row.findViewById(R.id.textView1);
viewHolder.number = (TextView)row.findViewById(R.id.quantity);
viewHolder.uniqueKey = String.valueOf(position);
add = (Button) row.findViewById(R.id.button1);
add.setTag(position);
sub = (Button) row.findViewById(R.id.button2);
sub.setTag(position);
row.setTag(viewHolder);
}
holder = (ViewHolder) row.getTag(); //keeping one global memory
holder.imageView.setImageResource(images[position]);
holder.textView.setText(names[position]);
add.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
count=count+1;
holder.number.setText(count.toString());
positiveNumbers.put(holder.uniqueKey,count); //Key -> String.valueOf(position) and Value -> int count
}
});
sub.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
count=count-1;
holder.number.setText(count.toString());
positiveNumbers.put(holder.uniqueKey,count); //Key -> String.valueOf(position) and Value -> int count
}
});
return row;
}
public Map<String,Integer> getPositiveNumbers()
{
return positiveNumbers;
}
}
附：我输入了编辑器,可能会有一些编译时错误.此外,您可以将每行的对象存储在键上,这样当您获得正数时,您可以获得任何其他参考,例如图像,我猜你需要稍后显示！
标签：listviewitem,android,listview,android-listview 来源： https://codeday.me/bug/20191003/1846540.html