Question

如果你看看我的代码。我希望在ListActivity中按下按钮时显示警报，在这种情况下位置0.当按下它时，我想要显示警报，允许用户创建新类别。我需要获取用户想要的字符串作为类别并将其添加到arraylist。请帮助我尝试了几个小时T_T

    public class Data extends ListActivity {
ArrayList<String> items = new ArrayList<String>();
private Context show;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    items.add("+ Create New");
    setListAdapter(new ArrayAdapter<String>(Data.this,
            android.R.layout.simple_list_item_1, items));

}

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
    // TODO Auto-generated method stub
    super.onListItemClick(l, v, position, id);
    if (position == 0) {
        items.add(getText());

    }

protected void getText() {

    AlertDialog.Builder alert = new AlertDialog.Builder(this);

    alert.setTitle("Title");
    // Set an EditText view to get user input
    final EditText input = new EditText(this);
    alert.setView(input);

    alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            Editable value = input.getText();

            // Need to add value to arraylist!
        }
    });
    alert.setNegativeButton("Cancel",
            new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int whichButton) {
                    // Canceled.
                }
            });

    alert.show();
}

}

...

我明白了。

protected void setCategory() {
    AlertDialog.Builder alert = new AlertDialog.Builder(this); 
    alert.setTitle("New Category"); 
    // Set an EditText view to get user input
    final EditText input = new EditText(this);
    alert.setView(input);

    alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
        //create a button that says ok, and can be pressed
        public void onClick(DialogInterface dialog, int whichButton) {
            Editable value = input.getText();
            getValue(value);
            //getValue() allows the string to be taken out of this method
            items.add(output);//put the string into the global variable
   /*
     * I dont understand why this way works over making "value" a string and             then             adding it
     * as the global variable.
     */
        }
    });
    alert.setNegativeButton("Cancel",
            new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int whichButton) {
                    //do nothing
                }
            });
    alert.show();
}
protected void getValue(Editable theInput) {
    String input = theInput.toString();
    output = input;
}

}

Answer 1

private ArrayAdapter<String> adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    items.add("+ Create New");
    adapter = new ArrayAdapter<String>(Data.this,
            android.R.layout.simple_list_item_1, items)
    setListAdapter(adapter);

}

alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {
        String inputText = input.getText().toString()
        adapter.add(inputText);
        /* if need add to items
        items.add(inputText);
        */
        }
});

需要从警报中向arraylist添加值

1 个答案: