带有微调器和复选框的 Android Listview [英] Android Listview with spinner and a checkbox
问题描述
我是安卓开发的新手.我正在尝试创建一个包含微调器、编辑文本和复选框的列表.微调器和复选框的数据来自数据库.我有以下文件.
I am a newbie to android development. I am trying to create a List which has a spinner, a edit text and a check box. The data for spinner and check box come from data base. I have the following files.
NewTransac class which extends ListActivity {
private PayDbAdapter mDbHelper;
private Spinner paySpinner;
private CheckBox mCheckBox;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.new_transac_listview);
mDbHelper = new PayDbAdapter(this);
mDbHelper.open();
populatedata();
}
private void populatedata() {
paySpinner = (Spinner)findViewById(R.id.payerspinner);
mCheckBox = (CheckBox)findViewById(R.id.paidforcheckboxname);
Cursor mCursor = mDbHelper.fetchAllTransactionValue();
startManagingCursor(mCursor);
// Create an array to specify the fields we want to display in the list.
String[] from = new String[]{PayDbAdapter.KEY_NAME};
int[] to = new int[]{android.R.id.text1};
int[] cbto = new int[]{R.id.paidforcheckboxname};
// Now create a simple cursor adapter and set it to display
SimpleCursorAdapter adapter =
new SimpleCursorAdapter(this, android.R.layout.simple_spinner_item, mCursor, from, to );
adapter.setDropDownViewResource( android.R.layout.simple_spinner_dropdown_item );
paySpinner.setAdapter(adapter);
SimpleCursorAdapter cbAdapter =
new SimpleCursorAdapter(this, R.layout.show_new_transac_data, mCursor, from, cbto );
setListAdapter(cbAdapter);
}
列表视图xml
<ListView android:id="@android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:drawSelectorOnTop="false"
android:textSize="14sp"
/>
<TextView android:id="@android:id/empty"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/no_friends"
android:textSize="14sp"
/>
<Button android:id="@+id/confirmpay"
android:text="@string/confirm"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal"
android:layout_gravity="center_vertical|center_horizontal|center">
</Button>
列表视图填充的xml
<TextView
style="?android:attr/listSeparatorTextViewStyle"
android:text="@string/listSeparatorPay"
android:layout_marginTop="5dip"
android:layout_marginBottom="5dip"
/>
<Spinner android:id="@+id/payerspinner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawSelectorOnTop="true"
android:prompt="@string/selectpayer"
/>
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/paytext"
/>
<EditText android:id="@+id/payamount"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:inputType="text"
/>
<TextView
style="?android:attr/listSeparatorTextViewStyle"
android:text="@string/listSeparatorPayedFor"
android:layout_marginTop="5dip"
android:layout_marginBottom="5dip"
/>
<CheckBox android:id="@+id/paidforcheckboxname"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
<EditText android:id="@+id/paidforamount"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="number"
/>
问题
我根据数据库中的字段数获得多个微调器、复选框和编辑文本.我看到我们无法像为微调器设置的那样为复选框设置适配器.我只需要获得一个带有一个编辑文本和多个复选框(数据库行总数)的微调器.请帮忙！
Problem
I get multiple spinners, checkboxes and edittext based on the number of fields in the database. I see that we cannot set the adapter for the checkbox as i set for the spinner.
I need to get only one spinner with one edit text and multiple checkboxes(total number of database rows). please help!
推荐答案
EDIT - 请查看评论，此解决方案可能不正确
我知道这个问题很古老，但它是 Google 上的第一个结果，我正在开发一个也在 ListView 中使用 Spinner 的应用程序.我使用了这里中的一些示例代码来开始.我希望这个例子能回答你的问题.我没有实现 CheckBoxes，但它们与 Spinner 非常相似 - 事实上要容易得多.此示例有一个带有 TextView 和 Spinner 的 ListView.每当用户更改微调器中的选择时，TextView 都会更改以反映这一点.
I know this question ancient, but it is the first result on Google and I am working on an application that uses Spinners in a ListView as well. I used some sample code from here to get started. I hope this example answers your question. I didn't implement the CheckBoxes but they're very similar to the Spinner - much easier, in fact. This example has a ListView with a TextView and a Spinner. Whenever the user changes a selection in the spinner, the TextView changes to reflect this.
我将这个项目分为 3 个类:
I divided this project up into 3 classes:
- ListViewTestActivity - 主要活动
- DataAdapter - 扩展 ArrayAdapter 并用于在 ListView 中显示元素
- DataHolder - 简单的对象，只保存有关元素的一些信息.这可以通过许多其他方式实现以满足您的需求.
我还修改/创建了 3 个关键的 Android XML 文件:
There are also 3 key Android XML files I modified / created:
- main.xml - 修改 - 主要布局
- rowview.xml - 添加 - ListView 中每个元素的布局
- strings.xml - 修改 - 默认的 Android 字符串文件
自下而上，这个 main.xml 文件只包含一个 ListView，没有别的:
To start from the bottom up, this main.xml file only contains a single ListView, and nothing else:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical"
android:layout_width="fill_parent" android:layout_height="fill_parent">
<ListView android:id="@+id/listView1" android:layout_height="match_parent" android:layout_width="match_parent" />
</LinearLayout>
这里是 rowview.xml.请记住，此视图为 ListView 中的每一行重复:
And here is the rowview.xml. Remember that this view is duplicated for each row in the ListView:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="match_parent"
android:layout_height="wrap_content" android:weightSum="1">
<TextView android:layout_width="wrap_content"
android:layout_height="match_parent" android:id="@+id/text"
android:layout_weight="0.5" android:textSize="25sp" />
<Spinner android:layout_width="0dp" android:layout_height="wrap_content"
android:id="@+id/spin" android:prompt="@string/choice_prompt"
android:layout_weight="0.5" />
</LinearLayout>
strings.xml 文件.我添加的只是一个包含微调器内容的数组:
The strings.xml file. All I added was an array for the contents of the spinner:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Hello World, ListViewTestActivity!</string>
<string name="app_name">ListViewTest</string>
<string name="choice_prompt">Select a choice</string>
<string-array name="choices">
<item>Alpha</item>
<item>Bravo</item>
<item>Charlie</item>
</string-array>
</resources>
现在是有趣的东西.ListViewActivity 类:
Now for the fun stuff. The ListViewActivity class:
public class ListViewTestActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ListView listView = (ListView) findViewById(R.id.listView1);
DataHolder data = new DataHolder(this);
DataHolder data1 = new DataHolder(this);
DataHolder data2 = new DataHolder(this);
DataHolder data3 = new DataHolder(this);
DataHolder data4 = new DataHolder(this);
DataAdapter d = new DataAdapter(this, R.layout.rowview, new DataHolder[] { data, data1, data2, data3, data4 });
listView.setAdapter(d);
}
}
这很简单，您只需获取列表，制作新适配器，然后将 ListView 的适配器设置为您制作的适配器即可.这是 DataHolder 类:
It's pretty simple, you just get the list, make a new adapter, and set the ListView's adapter to the one you made. This is the DataHolder class:
public class DataHolder {
private int selected;
private ArrayAdapter<CharSequence> adapter;
public DataHolder(Context parent) {
adapter = ArrayAdapter.createFromResource(parent, R.array.choices, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
}
public ArrayAdapter<CharSequence> getAdapter() {
return adapter;
}
public String getText() {
return (String) adapter.getItem(selected);
}
public int getSelected() {
return selected;
}
public void setSelected(int selected) {
this.selected = selected;
}
}
DataHolder 类所做的就是保存 Spinner 的适配器以及您可能想要为 ListView 中的每个条目存储的任何其他信息(例如，您可能想要存储它是否被选中).最后是应用程序的真正肉"，DataAdapter 类:
All the DataHolder class does is hold the Spinner's adapter and whatever other information you might want to store for each entry in the ListView (you may want to store whether it is checked or not, for example). And finally the real "meat" of the app, the DataAdapter class:
public class DataAdapter extends ArrayAdapter<DataHolder> {
private Activity myContext;
public DataAdapter(Activity context, int textViewResourceId, DataHolder[] objects) {
super(context, textViewResourceId, objects);
myContext = context;
}
// We keep this ViewHolder object to save time. It's quicker than findViewById() when repainting.
static class ViewHolder {
protected DataHolder data;
protected TextView text;
protected Spinner spin;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
// Check to see if this row has already been painted once.
if (convertView == null) {
// If it hasn't, set up everything:
LayoutInflater inflator = myContext.getLayoutInflater();
view = inflator.inflate(R.layout.rowview, null);
// Make a new ViewHolder for this row, and modify its data and spinner:
final ViewHolder viewHolder = new ViewHolder();
viewHolder.text = (TextView) view.findViewById(R.id.text);
viewHolder.data = new DataHolder(myContext);
viewHolder.spin = (Spinner) view.findViewById(R.id.spin);
viewHolder.spin.setAdapter(viewHolder.data.getAdapter());
// Used to handle events when the user changes the Spinner selection:
viewHolder.spin.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
viewHolder.data.setSelected(arg2);
viewHolder.text.setText(viewHolder.data.getText());
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
// Update the TextView to reflect what's in the Spinner
viewHolder.text.setText(viewHolder.data.getText());
view.setTag(viewHolder);
Log.d("DBGINF", viewHolder.text.getText() + "");
} else {
view = convertView;
}
// This is what gets called every time the ListView refreshes
ViewHolder holder = (ViewHolder) view.getTag();
holder.text.setText(getItem(position).getText());
holder.spin.setSelection(getItem(position).getSelected());
return view;
}
}
这是最终应用的屏幕截图(它不是很漂亮，但确实有效):
Here's a screenshot of the final app (it's not very pretty, but it does work):
就是这样！我希望我回答了您的问题并帮助了像我一样偶然发现它的任何其他人.如果要动态更改列表中的数据，请使用DataAdapter 的add()、remove()、get() 和set() 方法.要更改每个微调器的数据，您需要修改 DataHolder 类.SpinnerAdapter 在那里创建，因此您只需要根据数据库响应动态生成适配器.
And that's it! I hope I answered your question and helped anyone else who stumbled upon it like I did. If you want to dynamically change the data in the list, use the DataAdapter's add(), remove(), get(), and set() methods. To change the data for each individual spinner, you need to modify the DataHolder class. The SpinnerAdapter is created there, so you just need to dynamically generate the adapters depending on the database response.
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