CustomAdapter - CheckedTextView

Question

我在CheckTextView中的“记住”Checkboxes状态时遇到了问题。 现在，当我点击时，它会改变状态，但在不同的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; 
} 

}

现在我想用持有人弄清楚，但我听说，有可能使用SparseBooleanArray。有人可以解释如何使其工作？

编辑1 好吧，我有ListView是由CustomAdapter控制。该适配器只包含1个项目（CheckedTextView）。 问题是，滚动这些复选框后，不记得他们的状态。 我看到了你的答案和解释，但现在点击任何“CheckedTextView”后，其复选框的状态不会改变。

EDIT 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; 
} 

}

Answer 1

你必须保持一个布尔标志为每个CheckTextView。这可以是一个数组，List或SparseBooleanArray。数据结构选择应该是你的适配器的领域：

class CustomAdapterSmartwatch extends ArrayAdapter<String> { 
    private SparseBooleanArray checkedState = new SparseBooleanArray(); 

    // ... 
} 

你不想把它的持有人，因为持有人退休只有FR可见行。另一方面，您希望保持每行的检查状态，可见与否。

现在，您设置的存储选中状态，当用户点击一个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()); 
     } 
    }); 
} 

你恢复的选中状态，只要你吹一个角度还是从持有人重用一个：

@NonNull 
@Override 
public View getView(int position, View convertView, ViewGroup parent) { 
    // ... 

    holder.cTextView.setText(getItem(position)); 
    holder.cTextView.setChecked(checkedState.get(position)); 

    // ... 
} 

Answer 2

替换以下更新您的代码：

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; 
    } 
} 

Answer 3

您可以简单地使用视图onClick（）方法本身。

holder.cTextView.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      if(v instanceOf CheckedTextView) { 
       CheckedTextView c = (CheckedTextView) v; 
       c.setChecked(!c.isChecked()); 
      } 
     } 
    });