我试图在使用微调器选择排序样式时按字母顺序和数字顺序对列表视图中的项目进行排序。基本上每当用户选择一个微调器项时，列表视图将根据他们选择的选项进行排序。由于这是一个带有自定义适配器的自定义列表视图，因此我一直在寻找一种方法来实际对其进行实际排序。如果有人能就我如何做到这一点给我一些建议，我将不胜感激。 以下是我现在处理显示列表视图的主类：
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_repetition_progress);
/**
* The database used to pull all exercises for this workout routine
*/
DatabaseHandler db = new DatabaseHandler(this);
SQLiteDatabase database = db.getReadableDatabase();
context = this;
/**
* Get all exercises from Triceps and Chest workout and put in arraylist
*/
ListView workoutExerciseList = (ListView)findViewById(R.id.listView7);
final List<String> arrayRepetitionProgress = new ArrayList<String>();
exListAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, arrayRepetitionProgress);
workoutExerciseList.setAdapter(exListAdapter);
//Holds all the available exercises
final List<WorkoutTracker> exerciseList = db.getRepProgress(context, database);
/**
* Populates the listView with each exercise for this workout routine. This includes the
* each exercise name, the distance, the time of the workout, and any
* comments included.
*/
repProgressList = new ArrayList<RepetitionProgress.ListViewItem>();
for(int i = 0; i<exerciseList.size(); i++) {
final int j = i;
repProgressList.add(new ListViewItem()
{{
REPETITIONS = exerciseList.get(j).getReps();
WEIGHT = exerciseList.get(j).getWeight();
COMMENT = exerciseList.get(j).getComment();
EXERCISE_NAME = exerciseList.get(j).getExerciseName();
DATE = exerciseList.get(j).getDate();
}});
}
final RepetitionProgressAdapter adapter = new RepetitionProgressAdapter(this, repProgressList);
workoutExerciseList.setAdapter(adapter);
//Spinner used to select sorting method
SortOptions = (Spinner)findViewById(R.id.sortOption);
SortOptions.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
//If the Sort by exercise name option is chosen
if(SortOptions.getSelectedItem().toString().equals("Sort by exercise name")) {
Toast.makeText(context.getApplicationContext(), "Sort by exercise name", Toast.LENGTH_LONG).show();
exListAdapter.sort(new Comparator<String>() {
@Override
public int compare(String lhs, String rhs) {
return lhs.compareTo(rhs);
}
});
//Refresh the listview
adapter.notifyDataSetChanged();
exListAdapter.notifyDataSetChanged();
}
//If the Sort by date option is chosen
if(SortOptions.getSelectedItem().toString().equals("Sort by date")) {
Toast.makeText(context.getApplicationContext(), "Sort by date", Toast.LENGTH_LONG).show();
}
//If the Sort by number of repetitions option is chosen
if(SortOptions.getSelectedItem().toString().equals("Sort by number of repetitions")) {
Toast.makeText(context.getApplicationContext(), "Sort by number of repetitions", Toast.LENGTH_LONG).show();
}
//If the Sort by weight option is chosen
if(SortOptions.getSelectedItem().toString().equals("Sort by weight")) {
Toast.makeText(context.getApplicationContext(), "Sort by weight", Toast.LENGTH_LONG).show();
}
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
Back = (Button)findViewById(R.id.back);
Back.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
finish();
}
});
}
以下是我的自定义适配器类的一部分，它处理设置每个listview项中看到的属性：
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ListViewItem item = items.get(position);
View vi=convertView;
if(convertView==null)
vi = inflater.inflate(R.layout.rep_progress_view, null);
TextView exerciseName = (TextView)vi.findViewById(R.id.FullProgress);
TextView exerciseComment = (TextView)vi.findViewById(R.id.Comment);
exerciseName.setText(item.EXERCISE_NAME + " Date: " + item.DATE + " Reps: " + item.REPETITIONS + " Weight: " +item.WEIGHT + " Pounds ");
exerciseComment.setText(item.COMMENT);
return vi;
}
答案 0 :(得分：1)
下面是示例代码，您可以查看并对代码实现相同的内容。
public static void main(String[] args) {
List<Item> items = new ArrayList<>();
// constructor Item(name, Id, weight)
items.add(new Item("Nelson", 1, 10.3));
items.add(new Item("Fisk", 2, 12.03));
items.add(new Item("Speedy", 3, 19.3));
items.add(new Item("Donna", 4, 12.3));
items.add(new Item("Matt", 5, 16.3));
items.add(new Item("Oliver", 6, 1.3));
items.add(new Item("Deadstroke", 5, 1.3));
Collections.sort(items, new MyComparator(MyComparator.NAME));
for (Item item : items) {
System.out.println("Items " + item.getName() + " \t" + item.getWeight());
}
}
static class MyComparator implements Comparator<Item> {
static final int NAME = 0, WEIGHT = 1, DATE = 2;
int type;
public MyComparator(int type) {
this.type = type;
}
@Override
public int compare(Item o1, Item o2) {
if (type == NAME) {
return o1.getName().compareTo(o2.getName());
} else if (type == WEIGHT) {
if (o1.getWeight() > o2.getWeight())
return 1;
else if (o1.getWeight() == o2.getWeight())
return 0;
else
return -1;
} else if (type == DATE) {
// now convert your date object/string to milliseconds and apply
// number logic (above)
}
return 0;
}
}
以及如何调用Spinner，
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selectedItem = parent.getItemAtPosition(position).toString();
if (selectedItem.equals("Sort by exercise name")) {
// Collections.sort(items, new MyComparator(MyComparator.NAME));
//replace with your code/array list
} else if (selectedItem.equals("Sort by date")) {
// Collections.sort(items, new MyComparator(MyComparator.DATE));
} else if (selectedItem.equals("Sort by number of repetitions")) {
// Collections.sort(items, new MyComparator(MyComparator.REPTS));
} else if (selectedItem.equals("Sort by weight")) {
// Collections.sort(items, new MyComparator(MyComparator.WEIGHT));
}
adapter.notifyDataSetChanged();
exListAdapter.notifyDataSetChanged();
}