如何切换 ListView 项目颜色并保存？
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【中文标题】如何切换 ListView 项目颜色并保存？【英文标题】：How to toggle ListView item colors and Save it? 【发布时间】：2017-03-26 15:45:03 【问题描述】：我正在开发一个考勤应用程序。该应用程序有ListActivity 由学生列表组成。我想将颜色更改为红色和绿色，表示不存在和存在。问题是如果我的学生名单比屏幕长。当前视图向下或向上的项目会失去颜色。我的方法正确吗？如何保存每个单独列表项的颜色。当然，如果除了使用ListView 之外还有其他最佳方法，我愿意接受建议。
这是包含列表的 ListActivity
public class ListActivity extends Activity implements Serializable
private String userName;
private TextView nameTextView;
private ListView nameList;
private CustomAdapter adapter;
private boolean colorRed;
private Class myClass;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list);
myClass = new Class();
colorRed = false;
// Open the students list from file if exists
openFromFile();
nameList = (ListView) findViewById(R.id.nameListView);
nameTextView = (TextView) findViewById(R.id.nameTextView);
Bundle extras = getIntent().getExtras();
if (extras != null)
userName = extras.getString("NAME");
nameTextView.setText("Hi! " + userName);
adapter = new CustomAdapter(this, myClass.getStudentNames());
nameList.setAdapter(adapter);
TextView tv = (TextView) findViewById(R.id.sNametv);
nameList.setOnItemClickListener(new AdapterView.OnItemClickListener()
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long id)
if (colorRed == true)
view.setBackgroundColor(ContextCompat.getColor(getBaseContext(), R.color.colorPresent));
colorRed = false;
else
view.setBackgroundColor(ContextCompat.getColor(getBaseContext(), R.color.colorAbsent));
colorRed = true;
// ALso could use this
// adapterView.getChildAt(position).setBackgroundColor(Color.RED);
);
我使用boolean colorRed 来检查颜色，因为我无法将视图颜色与colors xml 的颜色进行比较。
nameList.setOnItemClickListener(new AdapterView.OnItemClickListener()
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long id)
if (colorRed == true)
view.setBackgroundColor(ContextCompat.getColor(getBaseContext(), R.color.colorPresent));
colorRed = false;
else
view.setBackgroundColor(ContextCompat.getColor(getBaseContext(), R.color.colorAbsent));
colorRed = true;
);
ListView 的CustomAdapter 类
public class CustomAdapter extends ArrayAdapter<String>
public CustomAdapter(Context context, ArrayList<String> names)
super(context, R.layout.custom_layout, names);
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent)
LayoutInflater inflater = LayoutInflater.from(getContext());
View customView = inflater.inflate(R.layout.custom_layout, parent, false);
String singleName = getItem(position);
TextView tv = (TextView) customView.findViewById(R.id.sNametv);
tv.setText(singleName);
return customView;
我已经仔细检查了这是一个独特的问题！放心……
提前致谢
【问题讨论】：
你使用的是POJO模型类？ 请明确！ 如果您将模型类用于列表项，那么您可以为每个项目创建另一个整数值并将其值设置为 1 或 0。然后在您的 getView 方法中检查该值并根据该值更改颜色。 好主意！但颜色变化不是永久性的。堆叠更多列表项后，颜色将丢失为默认的灰色。 您希望您的列表项永久使用另一种颜色？ 【参考方案1】：创建监听器接口：
public interface ListListener
void clickListItem(int position);
这是模型类：
public class Route
String studentName;
boolean colorRed;
public Route(String studentName, boolean colorRed)
this.studentName=studentName;
this.colorRed=colorRed;
public String getStudentName()
return studentName;
public void setStudentName(String studentName)
this.studentName = studentName;
public boolean isColorRed()
return colorRed;
public void setColorRed(boolean colorRed)
this.colorRed = colorRed;
创建适配器类：
public class AAdapter extends BaseAdapter implements View.OnClickListener
Context context;
private List<Route> routes;
Holder holder;
private static LayoutInflater inflater=null;
ListListener listListener;
public AAdapter(Context context, List<Route> names,ListListener listListener)
this.routes=names;
this.context=context;
this.listListener=listListener;
inflater = ( LayoutInflater )context.
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
@Override
public void onClick(View view)
listListener.clickListItem((Integer)view.getTag());
private class Holder
TextView tv;
@Override
public Route getItem(int position)
return routes.get(position);
@Override
public long getItemId(int position)
return position;
@Override
public int getCount()
return routes.size();
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent)
if (convertView==null)
holder=new Holder();
convertView=inflater.inflate(R.layout.custom_layout,null);
holder.tv=(TextView)convertView.findViewById(R.id.textView);
holder.tv.setOnClickListener(this);
convertView.setTag(holder);
else
holder=(Holder)convertView.getTag();
holder.tv.setText(routes.get(position).getStudentName());
holder.tv.setTag(position);
if (!routes.get(position).colorRed)
holder.tv.setBackgroundColor(Color.GREEN);
else
holder.tv.setBackgroundColor(Color.RED);
return convertView;
现在 MainActivity 类：
public class MainActivity extends AppCompatActivity implements ListListener
AAdapter adapter;
ListView lv;
List<Route> myNames;
ListListener listListener=MainActivity.this;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv=(ListView)findViewById(R.id.listnames);
myNames=new ArrayList<>();
/* DEMO DATA U NEED TO FETCH YOUR DATA */
myNames.add(new Route("FIRST",false));
myNames.add(new Route("Second",false));
myNames.add(new Route("Third",false));
myNames.add(new Route("Fourth",false));
myNames.add(new Route("Fifth",false));
myNames.add(new Route("FIRST",false));
myNames.add(new Route("Second",false));
myNames.add(new Route("Third",false));
myNames.add(new Route("Fourth",false));
myNames.add(new Route("Fifth",false));
myNames.add(new Route("FIRST",false));
myNames.add(new Route("Second",false));
myNames.add(new Route("Third",false));
myNames.add(new Route("Fourth",false));
myNames.add(new Route("Fifth",false));
myNames.add(new Route("FIRST",false));
myNames.add(new Route("Second",false));
myNames.add(new Route("Third",false));
myNames.add(new Route("Fourth",false));
myNames.add(new Route("Fifth",false));
adapter = new AAdapter(this, myNames,listListener);
lv.setAdapter(adapter);
adapter.notifyDataSetChanged();
@Override
public void clickListItem(int position)
if(myNames.get(position).colorRed)
myNames.get(position).colorRed=false;
else
myNames.get(position).colorRed=true;
adapter.notifyDataSetChanged();
【讨论】：
当然，很高兴与您合作。在下一个问题出现之前见！ 我也是。再见 你能帮我this problem 我不知道该问题的任何解决方案。以上是关于如何切换 ListView 项目颜色并保存？的主要内容，如果未能解决你的问题，请参考以下文章