我有一个列表显示了一堆对象的ListActivity。我想改变的背景和放大器;该行的基础上，在MonitorObject两个布尔值的状态文本颜色。

我需要扩展ArrayAdapter？如果是这样，一个code样品将大大pciated，因为我一直在试图弄明白了，但没有成功过几天AP $ P $。

 公共类LWM扩展ListActivity {
  @覆盖
  公共无效的onCreate（包savedInstanceState）{
    super.onCreate（savedInstanceState）;
    的setContentView（R.layout.list）;
    setListAdapter（新ArrayAdapter＆其中; MonitorObject＆GT;（此，R.layout.row，getMonitorObjects（）））;
  }

  私人列表＆LT; MonitorObject＆GT; getMonitorObjects（）{
    名单＆LT; MonitorObject＆GT; MOS =新的ArrayList＆LT; MonitorObject＆GT;（）;
    mos.add（新MonitorObject（15000，20000，25000））;
    mos.add（新MonitorObject（15000，14000，18000））;
    mos.add（新MonitorObject（15000，12000，14000））;
    mos.add（新MonitorObject（100，200，250））;
    mos.add（新MonitorObject（3000，2500，3500））;
    返回马鞍山;
  }
}
 

 公共类MonitorObject {
  私人诠释mTimeTotal;
  私人诠释mWarningThreshold;
  私人诠释mAlarmThreshold;`输入code here`
  私人布尔mWarning;
  私人布尔mAlarm;

  公共MonitorObject（INT timeTotal，诠释warningThreshold，诠释alarmThreshold）{
    this.mTimeTotal = timeTotal;
    this.mWarningThreshold = warningThreshold;
    this.mAlarmThreshold = alarmThreshold;
    mWarning =（mTimeTotal＆GT; mWarningThreshold）？真假;
    mAlarm =（mTimeTotal＆GT; mAlarmThreshold）？真假;
  }
  / *的getter，setter方法​​，的toString到这里* /
}
 

解决方案

我发现如何做到这一点在commonsware.com免费摘录的忙碌codeR指南Android开发一个伟大的教程。另外，请查阅谷歌I / O 2010 - ListView的在YouTube上的世界，它含有大量的有用的信息。

基本上我不得不这样做赤身创建自定义ArrayAdapter并重写getView（）。退房code波纹管。

 公共类LWM扩展ListActivity {
  私人TextView的mSelection;
  私人列表＆LT; MonitorObject＆GT; mMonitorObjects;

  @覆盖
  公共无效的onCreate（包savedInstanceState）{
    super.onCreate（savedInstanceState）;
    mMonitorObjects = getMonitorObjects（）;
    的setContentView（R.layout.main）;
    setListAdapter（新CustomAdapter（））;
    mSelection =（TextView中）findViewById（R.id.selection）;
  }

  @覆盖
  公共无效onListItemClick（ListView的父，视图V，INT位置，长的id）{
    mSelection.setText（选择长度为：+ mMonitorObjects.get（位置）的ToString（）长度（））;
  }

  私有类CustomAdapter扩展ArrayAdapter＆LT; MonitorObject＆GT; {
    CustomAdapter（）{
      超（Lwm.this，R.layout.row，R.id.label，mMonitorObjects）;
    }

    @覆盖
    公共查看getView（INT位置，查看convertView，ViewGroup中父）{
      查看排= convertView;

      如果（行== NULL）{
        //这给了我们一个视图对象返回其在现实中，我们的LinearLayout与
        //一个ImageView的和一个TextView，就像R.layout.row规定。
        LayoutInflater充气= getLayoutInflater（）;
        行= inflater.inflate（R.layout.row，父母，假）;
      }

      TextView的标签=（TextView中）row.findViewById（R.id.label）;
      label.setText（mMonitorObjects.get（位置）的ToString（））;
      ImageView的图标=（ImageView的）row.findViewById（R.id.icon）;

      。MonitorObject月= getMonitorObjects（）得到（位置）;

      如果（mo.ismAlarm（））{
        icon.setImageResource（R.drawable.alarm）;
        row.setBackgroundColor（Color.RED）;
      }否则如果（mo.ismWarning（））{
        icon.setImageResource（R.drawable.warning）;
        row.setBackgroundColor（Color.YELLOW）;
      } 其他 {
        icon.setImageResource（R.drawable.ok）;
        row.setBackgroundColor（Color.GREEN）;
      }

      返回行;
    }
  }

  私人列表＆LT; MonitorObject＆GT; getMonitorObjects（）{
    名单＆LT; MonitorObject＆GT; MOS =新的ArrayList＆LT; MonitorObject＆GT;（）;
    mos.add（新MonitorObject（15000，20000，25000））;
    mos.add（新MonitorObject（15000，14000，18000））;
    mos.add（新MonitorObject（15000，12000，14000））;
    mos.add（新MonitorObject（100，200，250））;
    mos.add（新MonitorObject（3000，2500，3500））;
    返回马鞍山;
  }
}
 

I have a ListActivity displaying a bunch of objects from a list. I want to change the background & text color of the row based on the state of the two booleans in the MonitorObject.

Do I need to extend ArrayAdapter? If so, a code sample would be greatly appreciated as I have been trying to figure it out for a few days with no success.

public class Lwm extends ListActivity {
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.list);
    setListAdapter(new ArrayAdapter<MonitorObject>(this, R.layout.row, getMonitorObjects()));
  }

  private List<MonitorObject> getMonitorObjects() {
    List<MonitorObject> mos = new ArrayList<MonitorObject>();
    mos.add(new MonitorObject(15000, 20000, 25000));
    mos.add(new MonitorObject(15000, 14000, 18000));
    mos.add(new MonitorObject(15000, 12000, 14000));
    mos.add(new MonitorObject(100, 200, 250));
    mos.add(new MonitorObject(3000, 2500, 3500));
    return mos;
  }
}

public class MonitorObject {
  private int mTimeTotal;
  private int mWarningThreshold;
  private int mAlarmThreshold;`enter code here`
  private boolean mWarning;
  private boolean mAlarm;

  public MonitorObject(int timeTotal, int warningThreshold, int alarmThreshold) {
    this.mTimeTotal = timeTotal;
    this.mWarningThreshold = warningThreshold;
    this.mAlarmThreshold = alarmThreshold;  
    mWarning = (mTimeTotal > mWarningThreshold) ? true : false;
    mAlarm = (mTimeTotal > mAlarmThreshold) ? true : false;
  }
  /*getters, setters, tostring goes here*/
}

I found a great tutorial on how to do this in the free excerpt for 'The Busy Coder's Guide to Android Development' at commonsware.com. Also check out Google I/O 2010 - The world of ListView at youtube, it contains lots of useful information.

Basically what I had to do wast to create a custom ArrayAdapter and override getView(). Check out the code bellow.

public class Lwm extends ListActivity {
  private TextView mSelection;
  private List<MonitorObject> mMonitorObjects;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mMonitorObjects = getMonitorObjects();
    setContentView(R.layout.main);
    setListAdapter(new CustomAdapter());
    mSelection = (TextView)findViewById(R.id.selection);
  }

  @Override
  public void onListItemClick(ListView parent, View v, int position, long id){
    mSelection.setText("Selection length is: " + mMonitorObjects.get(position).toString().length());
  }

  private class CustomAdapter extends ArrayAdapter<MonitorObject> {
    CustomAdapter() {
      super(Lwm.this, R.layout.row, R.id.label, mMonitorObjects);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {     
      View row = convertView;

      if (row == null) {
        // This gives us a View object back which, in reality, is our LinearLayout with 
        // an ImageView and a TextView, just as R.layout.row specifies.
        LayoutInflater inflater = getLayoutInflater();      
        row = inflater.inflate(R.layout.row, parent, false);
      }

      TextView label = (TextView) row.findViewById(R.id.label);
      label.setText(mMonitorObjects.get(position).toString());
      ImageView icon = (ImageView)row.findViewById(R.id.icon);

      MonitorObject mo = getMonitorObjects().get(position);

      if (mo.ismAlarm()) {
        icon.setImageResource(R.drawable.alarm);
        row.setBackgroundColor(Color.RED);
      } else if (mo.ismWarning()){
        icon.setImageResource(R.drawable.warning);
        row.setBackgroundColor(Color.YELLOW);
      } else {
        icon.setImageResource(R.drawable.ok);
        row.setBackgroundColor(Color.GREEN);
      }

      return row;       
    }
  }

  private List<MonitorObject> getMonitorObjects() {
    List<MonitorObject> mos = new ArrayList<MonitorObject>();
    mos.add(new MonitorObject(15000, 20000, 25000));
    mos.add(new MonitorObject(15000, 14000, 18000));
    mos.add(new MonitorObject(15000, 12000, 14000));
    mos.add(new MonitorObject(100, 200, 250));
    mos.add(new MonitorObject(3000, 2500, 3500));
    return mos;
  }
}