我在CheckTextView中“记住”Checkbox的状态时遇到问题。 现在当我点击它时,它会改变状态,但是在不同的CheckBox上。
class CustomAdapterSmartwatch extends ArrayAdapter<String> {
static class ViewHolder {
protected CheckedTextView cTextView;
}
ViewHolder holder;
public CustomAdapterSmartwatch(Context context, ArrayList<String> variables) {
super(context,R.layout.row_smartwatch_resources,variables);
}
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater smartwatchinflater = LayoutInflater.from(getContext());
convertView = smartwatchinflater.inflate(R.layout.row_smartwatch_resources,parent,false);
holder.cTextView = (CheckedTextView) convertView.findViewById(R.id.row_smartwatch_checked);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.cTextView.setText(getItem(position));
holder.cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (holder.cTextView.isChecked()) {
holder.cTextView.setChecked(false);
} else {
holder.cTextView.setChecked(true);
}
}
});
return convertView;
}
}
现在我想弄清楚使用Holder,但我听说可以使用SparseBooleanArray。有人可以解释如何使其有效吗?
编辑1 好的,我有ListView,由CustomAdapter控制。该适配器只包含1个项目(CheckedTextView)。 问题是滚动后这些复选框不记得它们的状态。 我看到你的答案有解释,但现在点击任何“CheckedTextView”后,他们的复选框状态不会改变。
编辑2
@NonNull
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater smartwatchinflater = LayoutInflater.from(getContext());
convertView = smartwatchinflater.inflate(R.layout.row_smartwatch_resources,parent,false);
holder.cTextView = (CheckedTextView) convertView.findViewById(R.id.row_smartwatch_checked);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.d("MainActivity","Position = " + position);
CheckedTextView checkedText = (CheckedTextView) v;
checkedState.put(position, !checkedText.isChecked());
Log.d("MainActivity","State = " + checkedState.get(position));
}
});
holder.cTextView.setText(getItem(position));
holder.cTextView.setChecked(checkedState.get(position));
return convertView;
}
编辑3
class CustomAdapterSmartwatch extends ArrayAdapter<String> {
public SparseBooleanArray checkedState = new SparseBooleanArray();
private CheckedTextView cTextView;
public CustomAdapterSmartwatch(Context context, ArrayList<String> variables) {
super(context,R.layout.row_smartwatch_resources,variables);
}
@NonNull
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater smartwatchinflater = LayoutInflater.from(getContext());
convertView = smartwatchinflater.inflate(R.layout.row_smartwatch_resources,parent,false);
cTextView = (CheckedTextView) convertView.findViewById(R.id.row_smartwatch_checked);
cTextView.setText(getItem(position));
cTextView.setChecked(checkedState.get(position));
cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.d("MainActivity","Position = " + position);
CheckedTextView checkedText = (CheckedTextView) v;
checkedText.toggle();
if (checkedText.isChecked())
checkedState.put(position,true);
else
checkedState.delete(position);
Log.d("MainActivity","State = " + checkedState.get(position));
}
});
return convertView;
}
}
答案 0 :(得分:0)
您必须为每个CheckTextView保留一个布尔标志。这可以是数组,List或SparseBooleanArray。您选择的数据结构应该是适配器的字段:
class CustomAdapterSmartwatch extends ArrayAdapter<String> {
private SparseBooleanArray checkedState = new SparseBooleanArray();
// ...
}
您不希望将其放入持有者,因为持有人仅在可见行中退役。另一方面,您希望保持每行的已检查状态,可见或不可见。
现在,当用户点击CheckedTextView
:
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// ...
holder.cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
CheckedTextView checkedText = (CheckedTextView)v;
checkedState.put(position, checkedText.isChecked());
}
});
}
每当您为视图充气或重新使用持有者时,您都会恢复已检查状态:
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// ...
holder.cTextView.setText(getItem(position));
holder.cTextView.setChecked(checkedState.get(position));
// ...
}
答案 1 :(得分:-1)
使用以下更新替换您的代码:
class CustomAdapterSmartwatch extends ArrayAdapter<CustomAdapterSmartwatch.MyPojo> {
class MyPojo {
boolean checked;
String data;
public boolean isChecked() {
return checked;
}
public void setChecked(boolean checked) {
this.checked = checked;
}
public String getData() {
return data;
}
public void setData(String data) {
this.data = data;
}
}
static class ViewHolder {
protected CheckedTextView cTextView;
}
ViewHolder holder;
public CustomAdapterSmartwatch(Context context, ArrayList<MyPojo> variables) {
super(context, R.layout.row_smartwatch_resources, variables);
}
@Nullable
@Override
public MyPojo getItem(int position) {
return super.getItem(position);
}
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater smartwatchinflater = LayoutInflater.from(getContext());
convertView = smartwatchinflater.inflate(R.layout.row_smartwatch_resources,parent,false);
holder.cTextView = (CheckedTextView) convertView.findViewById(R.id.row_smartwatch_checked);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final MyPojo item = getItem(position);
holder.cTextView.setText(item.getData());
holder.cTextView.setChecked(item.isChecked());
holder.cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
boolean nextStatus = !item.isChecked();
item.setChecked(nextStatus);
holder.cTextView.setChecked(nextStatus);
}
});
return convertView;
}
}
答案 2 :(得分:-1)
您只需在onClick()方法中使用该视图。
holder.cTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(v instanceOf CheckedTextView) {
CheckedTextView c = (CheckedTextView) v;
c.setChecked(!c.isChecked());
}
}
});