ListView无法响应Android中的点击事件

Question

我有一个自定义ListView项目如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" 
    android:gravity="center_vertical" 
    android:paddingTop="2dp"
    android:paddingBottom="2dp"
    android:background="@android:color/transparent">

    <ImageView
        android:id="@+id/profile_picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/mr_unknown" 
        android:contentDescription="@string/profile_picture_description"
        android:paddingRight="3dp"/>

    <TextView
        android:id="@+id/real_life_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        style="@style/FriendListText"/>
    <Button 
        android:id="@+id/ping_friend"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Ping Friend"
        />
</LinearLayout>

在这个ListView中使用:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:background="@color/white"
    tools:context=".FriendListActivity" >

    <ListView
        android:id="@+id/friend_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:fastScrollEnabled="true"
        android:smoothScrollbar="false"
        style="@style/ListViewStyle" >
    </ListView>

</LinearLayout>

现在我希望当任何列表项上点击Ping Friend按钮时它应该显示AlertDialog.我用过这段代码......

friendListAdapter = new FriendListAdapter(FriendListActivity.this, friends);
friendListView = (ListView) findViewById(R.id.friend_list);
friendListView.setAdapter(friendListAdapter);           

downloadFriends_async(); //This method downloads all the *friends* into ListView from Database. *Its working correctly*.


friendListView.setOnItemClickListener(new OnItemClickListener() {

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);
        alertDialogBuilder.setTitle("Hello!!!");
        alertDialogBuilder
        .setMessage("Do you want to exit?")
        .setCancelable(false)
        .setPositiveButton("Yes",new DialogInterface.OnClickListener() {

            public void onClick(DialogInterface dialog,int id) {
                FriendListActivity.this.finish();}})
                .setNegativeButton("No",new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog,int id) {
                        dialog.cancel();}});
        AlertDialog alertDialog = alertDialogBuilder.create();
        alertDialog.show();
    }
});

没有显示错误.

问题是它没有响应Click on Button而且根本没有出现AlertDialog.

对于按钮我也累了加入内部onItemClick的ListView控件:

public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

Button btnPingFriend = (Button) findViewById(R.id.ping_friend);
btnPingFriend.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View view) {

//Rest of AlertDialog Code...

}

仍然没有回应.

请建议.

Answer 1

加

android:descendantFocusability="blocksDescendants"

到你的项目的顶部ViewGroup

更新:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" 
    android:gravity="center_vertical" 
    android:paddingTop="2dp"
    android:paddingBottom="2dp"
    android:background="@android:color/transparent"
    android:descendantFocusability="blocksDescendants"
     >

    <ImageView
        android:id="@+id/profile_picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/mr_unknown" 
        android:contentDescription="@string/profile_picture_description"
        android:paddingRight="3dp"/>

    <TextView
        android:id="@+id/real_life_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        style="@style/FriendListText"/>
    <Button 
        android:id="@+id/ping_friend"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Ping Friend"
        />
</LinearLayout>