我有一个 ListView，它处于 singleChoice 模式。我想要的只是在侧面显示一个 RadioButton，当单击它时会突出显示它被选中，当单击另一个按钮时，它会隐藏并选择新的按钮。
我查看了 Mark 的书，第 8 章，“开始喜欢列表”和他的 RateList 示例
但这并不能解决我的问题。
请帮帮我。
【问题讨论】：
标签： android listview radio-button listviewitem
编辑
值得一提的是，我的列表项有一个自定义布局：有一个图标、一个标题、一个描述，然后是复选框或单选按钮（取决于它是单选还是多选列表）。我的示例解决方案是，因此由不少于三个不同的部分描述：
ListView 配置示例Adapter::getView() 实施示例。
那么让我们来看看魔法吧？
listitem.xml
<com.dbm.CheckableLinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView
android:layout_width="32dp"
android:layout_height="32dp"
android:id="@+id/myIcon" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAppearance="@android:style/TextAppearance.Medium"
android:textStyle="bold"
android:ellipsize="end"
android:id="@+id/myTitle" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAppearance="@android:style/TextAppearance.Small"
android:textStyle="italic"
android:ellipsize="end"
android:id="@+id/myDescr" />
</LinearLayout>
<CheckedTextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@android:id/text1" />
</com.dbm.CheckableLinearLayout>
CheckableLinearLayout.java
public class CheckableLinearLayout extends LinearLayout implements Checkable {
private CheckedTextView mCheckedTextView;
private final Drawable mCheckDrawable;
private final Drawable mRadioDrawable;
private boolean mIsChecked;
/**
* Constructor.
*
* @param context The context to operate in.
* @param attrs The attributes defined in XML for this element.
*/
public CheckableLinearLayout(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray typedArray = null;
// Cache the check box drawable.
typedArray = context.getTheme().obtainStyledAttributes(new int[] {android.R.attr.listChoiceIndicatorMultiple});
if ((typedArray != null) && (typedArray.length() > 0)) {
mCheckDrawable = typedArray.getDrawable(0);
}
else {
// Fallback if the target theme doesn't define a check box drawable.
// Perhaps an application specific drawable should be used instead of null.
mCheckDrawable = null;
}
// Careful with resources like this, we don't need any memory leaks.
typedArray.recycle();
// Cache the radio button drawable.
typedArray = context.getTheme().obtainStyledAttributes(new int[] {android.R.attr.listChoiceIndicatorSingle});
if ((typedArray != null) && (typedArray.length() > 0)) {
mRadioDrawable = typedArray.getDrawable(0);
}
else {
// Fallback if the target theme doesn't define a radio button drawable.
// Perhaps an application specific drawable should be used instead of null
mRadioDrawable = null;
}
// Careful with resources like this, we don't need any memory leaks.
typedArray.recycle();
mIsChecked = false;
}
/*
* (non-Javadoc)
* @see android.widget.Checkable#isChecked()
*/
public boolean isChecked() {
return mIsChecked;
}
/*
* (non-Javadoc)
* @see android.view.View#onAttachedToWindow()
*/
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
// Check if there is a valid GUI element that can visualize the current check-state.
if (mCheckedTextView != null) {
ViewParent p = getParent();
// Check if the parent of this list item is a ListView
if (p instanceof ListView) {
int choiceMode = ((ListView) p).getChoiceMode();
// Decide which check-state notation to visualize (check box, radio button or none).
switch (choiceMode) {
case ListView.CHOICE_MODE_MULTIPLE:
mCheckedTextView.setCheckMarkDrawable(mCheckDrawable);
break;
case ListView.CHOICE_MODE_SINGLE:
mCheckedTextView.setCheckMarkDrawable(mRadioDrawable);
break;
default:
mCheckedTextView.setCheckMarkDrawable(null);
break;
}
}
}
}
/*
* (non-Javadoc)
* @see android.view.View#onFinishInflate()
*/
@Override
protected void onFinishInflate() {
super.onFinishInflate();
mCheckedTextView = (CheckedTextView) findViewById(android.R.id.text1);
}
/*
* (non-Javadoc)
* @see android.widget.Checkable#setChecked(boolean)
*/
public void setChecked(boolean checked) {
mIsChecked = checked;
if (mCheckedTextView != null) {
mCheckedTextView.setChecked(mIsChecked);
}
}
/*
* (non-Javadoc)
* @see android.widget.Checkable#toggle()
*/
public void toggle() {
setChecked(!mIsChecked);
}
}
exampleListView.xml
注意！如果您将android:choiceMode 属性设置为"multipleChoice"，您将自动获得复选框，如果您将其设置为"singleChoice"，您将自动获得单选按钮，前提是您使用上述实现。
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:choiceMode="singleChoice"
android:id="@+id/myList" />
</LinearLayout>
奖励：MyCustomAdapter::getView()
这个依赖于光标。当然，您可以根据自己的需要实施它。
private final class ViewHolder {
public ImageView iconView;
public TextView titleView;
public TextView descriptionView;
}
/*
* (non-Javadoc)
* @see android.widget.Adapter#getView(int, android.view.View, android.view.ViewGroup)
*/
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
// Only do something if the requested position exists within the Cursor.
if (mCursor.moveToPosition(position)) {
ViewHolder viewHolder;
view = convertView;
if (view == null) {
// Create and initialize a new view if not created already for this position.
view = mLayoutInflater.inflate(R.layout.listitem, null);
// Don't "find view by id" each and every time, but rather save a reference
// to them and associate the references with the list item itself by storing
// them in the list items "tag" attribute. When the view is re-used later on,
// you already have a reference to its views and don't need to find them
// again, which is a time-consuming operation.
viewHolder = new ViewHolder();
viewHolder.iconView = (ImageView) view.findViewById(R.id.myIcon);
viewHolder.titleView = (TextView) view.findViewById(R.id.myTitle);
viewHolder.descriptionView = (TextView) view.findViewById(R.id.myDescr);
view.setTag(viewHolder);
}
else {
// Get the references to the views for this, already existing list item.
viewHolder = (ViewHolder) view.getTag();
}
// Create a bitmap from the byte array in the database.
byte[] buffer = mCursor.getBlob(mIconColumnIndex);
Bitmap icon = null;
// Try to decode the byte array if it exists.
if (buffer != null) {
icon = BitmapFactory.decodeByteArray(buffer, 0, buffer.length);
}
// Update the views with new data.
viewHolder.iconView.setImageBitmap(icon);
String title = mCursor.getString(mTitleColumnIndex);
viewHolder.titleView.setText(title);
String description = mCursor.getString(mDescriptionColumnIndex);
viewHolder.descriptionView.setText(description);
}
// Return a view showing the correct data for the item at 'position'.
return view;
}
原始答案：
我可以推荐这个链接：
http://tokudu.com/2010/android-checkable-linear-layout/
当我处于您的确切位置时，我本人对此感到非常高兴 :-) 如果仍有任何不清楚的地方，请随时指定您的问题，我很乐意帮助或协助提供更多代码示例（就像前面提到过：我几天前才担任您的职位）。
【讨论】：
我使用了dbm's answer，它对我来说很好，除了一件事：
您应该在onAttachedToWindow() 方法中启动CheckedTextView，而不是在onFinishInflate(). 这是因为onAttachedToWindow() 调用了之前 onFinishInflate() 并且使用上面的解决方案您将永远看不到任何可绘制对象CheckedTextView——调用onAttachedToWindow()时为空。
【讨论】：