Question

我目前正在开发一个文件资源管理器应用程序，我需要为我的列表视图自动刷新。因为当我删除项目时，我仍然可以看到该项目，我需要备份文件夹并再次进入文件夹，只看到它消失。如何自动刷新所以当我删除项目时它会消失。

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {

    super.onListItemClick(l, v, position, id);
    FileInfo fileDescriptor = fileArrayListAdapter.getItem(position);
    if (fileDescriptor.isFolder() || fileDescriptor.isParent()) {
        currentFolder = new File(fileDescriptor.getPath());
        fill(currentFolder);
        //


    } else {

        fileSelected = new File(fileDescriptor.getPath());
        Intent intent = new Intent();
        intent.putExtra(Constants.KEY_FILE_SELECTED,
                fileSelected.getAbsolutePath());
        setResult(Activity.RESULT_OK, intent);
        Log.i("FILE CHOOSER", "result ok");



            MimeTypeMap map = MimeTypeMap.getSingleton();
            String ext = MimeTypeMap.getFileExtensionFromUrl(fileSelected.getName());
            String type = map.getMimeTypeFromExtension(ext);

            if (type == null){
                type = "*/.jpeg*";

            intent.setAction(android.content.Intent.ACTION_VIEW);
            intent.setDataAndType(Uri.fromFile(fileSelected), "image/*");

          //  intent.setDataAndType(data, type);
            }else {
                 type = "*/.txt*";

                    intent.setAction(android.content.Intent.ACTION_VIEW);
                    intent.setDataAndType(Uri.fromFile(fileSelected), "text/*");

                 //   intent.setDataAndType(data, type);
            }
        //finish();


    //  intent.setAction(android.content.Intent.ACTION_VIEW);

        startActivity(intent); 
    //  Intent intent = new Intent();




        this.getListView().setLongClickable(true);
        this.getListView().setOnItemLongClickListener(new OnItemLongClickListener() {
            public boolean onItemLongClick(AdapterView<?> parent, View v, int position, long id) {
        new AlertDialog.Builder(ViewNoteActivity.this) .setTitle("Delete File")
        .setMessage("Do You Want To Delete this file ?")
        .setPositiveButton("Yes", new DialogInterface.OnClickListener(){
            public void onClick(DialogInterface dialog, int button){
                fileSelected.delete();
                Toast.makeText(getBaseContext(), "File has been deleted." , Toast.LENGTH_SHORT ).show();
                adapter.notifyDataSetChanged();
            }

        })
        .setNegativeButton("No", new DialogInterface.OnClickListener(){
        public void onClick(DialogInterface dialog, int button){
            }
        }).show();
         return true;
            }
        });

    }
}



public static boolean deleteDir(File dir) {
    if (dir.isDirectory()) {
        String[] children = dir.list();
        for (int i=0; i<children.length; i++) {
            boolean success = deleteDir(new File(dir, children[i]));
            if (!success) {
                return false;
            }
        }
    }
    return dir.delete();

}

Answer 1

从填充listview的数据源中删除项目，并在适配器上调用notifyDataSetChanged以刷新listView

Answer 2

您需要从Adapter中删除ArrayList中的ListItem并调用notifyDatasetChanged（），当你调用notifyDatasetChanged（）方法时，它将使用带有更新数据的ArrayList刷新listview，因此，你必须首先从删除按钮上的ArrayList中删除项目。然后你必须调用notifyDatasetChanged（）。

Android java：如何自动刷新列表视图

2 个答案: