我一直在尝试了解android中的列表和其他东西..我有一个应用程序，显示来自SD卡的项目列表..我想要的代码，我可以添加排序选项到它...其中将按名称，日期，类型和大小对列表进行排序。请帮帮我.. 我在这里显示我的代码..它在列表视图中显示内容。
package com.android.sam;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener ;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.Context;
import android.content.DialogInterface;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
public class SamActivity extends ListActivity {
private List<String> item = null;
private List<String> path = null;
private String root="/";
private TextView myPath;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myPath = (TextView)findViewById(R.id.path);
getDir(root);
}
private void getDir(String dirPath)
{
myPath.setText("Location: " + dirPath);
item = new ArrayList<String>();
path = new ArrayList<String>();
File f = new File(dirPath);
File[] files = f.listFiles();
if(!dirPath.equals(root))
{
item.add(root);
path.add(root);
item.add("../");
path.add(f.getParent());
}
for(int i=0; i < files.length; i++)
{
File file = files[i];
path.add(file.getPath());
if(file.isDirectory())
item.add(file.getName() + "/");
else
item.add(file.getName());
}
ArrayAdapter<String> fileList =
new ArrayAdapter<String>(this, R.layout.row, item);
setListAdapter(fileList);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
File file = new File(path.get(position));
if (file.isDirectory())
{
if(file.canRead())
getDir(path.get(position));
else
{
new AlertDialog.Builder(this)
.setIcon(R.drawable.ic_launcher)
.setTitle("[" + file.getName() + "] folder can't be read!")
.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
}).show();
}
}
else
{
new AlertDialog.Builder(this)
.setIcon(R.drawable.alert)
.setTitle("[" + file.getName() + "] ")
.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
}).show();
}
}
}
在我的布局中，我添加了一个图像按钮，该按钮应显示排序选项并对列表进行排序 谢谢你提前 这就是我所添加的内容 `sorting =（Button）findViewById（R.id.button2）; 最终上下文context1 = this; sorting.setOnClickListener（new OnClickListener（）{
public void onClick(View v) {
if (v == findViewById(R.id.button2)) {
final CharSequence[] items = {"name", "date", "size", "type", "none"};
AlertDialog.Builder builder = new AlertDialog.Builder(context1);
builder.setTitle("Sort by");
builder.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener () {
// Click listener
public void onClick(DialogInterface dialog, int item) {
Toast.makeText(getApplicationContext(), items[item], Toast.LENGTH_SHORT).show();
//If the Cheese item is chosen close the dialog box
if(items[item]=="none")
dialog.dismiss();
}
});
AlertDialog alert = builder.create();
//display dialog box
alert.show();
}
}
});
答案 0 :(得分：0)
1-你想要对String对象的ArrayList进行排序，因为ArrayList可以使用Collections.sort（item）;
2-如果你有对象类型的ArrayList需要为它创建Comparator。