我花了几个小时试图解决这个问题，虽然我已经接近了，但我没有得到我需要的结果。我有一个消息传递应用程序，它有一个自定义适配器和一个包含大约 5 个 TextView 的 ListView 。我的问题是当用户长按消息时检索文本。在尝试了各种方法之后，我最接近的是:
mListView.setOnItemLongClickListener( new AdapterView.OnItemLongClickListener
(){
public boolean onItemLongClick(AdapterView<?> av, View v, int pos, long id) {
final String test = ((TextView)v).getText().toString();
Log.i(TAG, "Received: " + test);
return true;
}
});
关于此代码的愚蠢(读:令人沮丧)部分是，单击时它会成功运行大约 3-4 次，但之后它会强制关闭我的应用程序。我得到的错误是:
FATAL EXCEPTION: main
java.lang.ClassCastException: android.widget.RelativeLayout cannot be cast to android.widget.TextView
at android.widget.AbsListView.performLongPress(AbsListView.java:3347)
at android.widget.AbsListView$CheckForLongPress.run(AbsListView.java:3294)
at android.os.Handler.handleCallback(Handler.java:725)
奇怪的是，我前几次成功获得了正确的消息字符串，然后它就不想工作了。查找错误后，我尝试多次清理项目、删除 R.java 文件并关闭 Eclipse，但没有任何效果。
我也尝试过使用消息的位置编号。在获取消息的位置号时，应用程序永远不会强制关闭，但是我无法让它获取附加到该位置消息的字符串。错误是关于尝试从整数转换为字符串:
String test = ((EditText)av.getItemAtPosition(pos)).getText().toString();
我的 xml 文件包含:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="horizontal" >
<LinearLayout
android:id="@+id/left"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_margin="20dip"
android:background="@drawable/bubble_yellow"
android:gravity="left"
android:orientation="vertical"
android:visibility="invisible" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="right"
android:paddingBottom="1dip"
android:paddingLeft="15dip"
android:paddingRight="20dip"
android:paddingTop="1dip"
android:singleLine="false"
android:text="Large Text"
android:longClickable="true"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:gravity="right"
android:paddingRight="20dip"
android:longClickable="true"
android:text="TextView" />
</LinearLayout>
<LinearLayout
android:id="@+id/right"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_margin="20dip"
android:background="@drawable/bubble_green"
android:orientation="vertical"
android:visibility="invisible" >
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingBottom="1dip"
android:paddingLeft="15dip"
android:paddingRight="20dip"
android:paddingTop="1dip"
android:singleLine="false"
android:longClickable="true"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:gravity="right"
android:longClickable="true"
android:paddingRight="20dip"
android:text="TextView" />
</LinearLayout>
</RelativeLayout>
更新 1:添加了请求的 xml 文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/background2"
android:orientation="vertical" >
<ListView
android:id="@+id/lv"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:divider="@null"
android:dividerHeight="0dp"
android:longClickable="true"
android:stackFromBottom="true" >
</ListView>
<View
android:layout_width="match_parent"
android:layout_height="1dp" />
<LinearLayout
android:id="@+id/sendMsgLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:layout_marginTop="20dp"
android:orientation="horizontal" >
<EditText
android:id="@+id/messageText"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_weight="1"
android:hint="Type Message"
android:inputType="textCapSentences|textMultiLine"
android:textColor="#FFFFFF"
android:maxLines="3" >
<requestFocus />
</EditText>
<ImageView
android:id="@+id/imageSend"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:src="@drawable/send512" />
</LinearLayout>
</LinearLayout>
更新2:我的适配器包含以下内容:
ViewHolder viewHolder;
MessageModel array = data.get(position);
if (convertView == null) {
viewHolder = new ViewHolder();
convertView = inflater.inflate(R.layout.message_item, null);
viewHolder.left =(LinearLayout)convertView.findViewById(R.id.left);
viewHolder.right =(LinearLayout)convertView.findViewById(R.id.right);
viewHolder.txt1 = (TextView) convertView
.findViewById(R.id.textView1);
viewHolder.txt3 = (TextView) convertView
.findViewById(R.id.textView3);
viewHolder.txt2 = (TextView) convertView
.findViewById(R.id.textView2);
viewHolder.txt4 = (TextView) convertView
.findViewById(R.id.textView4);
convertView.setTag(viewHolder);
更新3:我尽力遵循@MDragon00的建议，不幸的是我的应用程序在长按时仍然崩溃。我现在有:
mListView.setOnItemLongClickListener( new AdapterView.OnItemLongClickListener
(){
public boolean onItemLongClick(AdapterView<?> av, View v, int pos, long id) {
TextView textView1 = (TextView) v.findViewById(R.id.textView1);
TextView textView2 = (TextView) v.findViewById(R.id.textView2);
TextView textView3 = (TextView) v.findViewById(R.id.textView3);
TextView textView4 = (TextView) v.findViewById(R.id.textView4);
View.OnLongClickListener listener = new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
TextView textView = (TextView) v;
String text = textView.getText().toString();
Log.i(TAG, "Text Selected = " + text);
return false;
}
};
textView1.setOnLongClickListener(listener);
textView2.setOnLongClickListener(listener);
textView3.setOnLongClickListener(listener);
textView4.setOnLongClickListener(listener);
return true;
}
});
}
最佳答案
onItemLongClick中各个参数作用的说明:http://developer.android.com/reference/android/widget/AdapterView.OnItemLongClickListener.html
这里的问题是 av 是整个 ListView，而 v 是整个行。您的行不仅仅包含 TextView，因此您无法将其转换为 TextView。换句话说，
final String test = ((TextView)v).getText().toString();
这不是一个好主意，因为父 View 是一个RelativeLayout。更好的解决方案是执行以下操作:
TextView textView = (TextView) v.findViewById(R.id.idOfTextView);
String text = textView.getText().toString();
作为一个小建议，听起来您只想简单地单击该项目，而不是长时间单击它。如果适合您的需要，请使用 OnItemClickListener 而不是 OnItemLongClickListener。
编辑: 根据您的评论，用户将在某个抽象行中的多个 TextView 中单击/点击某个 TextView，并且您想要获取这四个 TextView 之一。
为此，您需要在每个 TextView 上有一个新的监听器。如果没有看到您的适配器，我无法给出确切的答案，但是当您膨胀/获取行 View 以提供给适配器中的 ListView 时，请将 OnClickListener 设置为 TextViews。例如一些伪代码:
// Get the textViews, to assign a listener to them
TextView textView1 = (TextView) v.findViewById(R.id.textView1);
TextView textView2 = (Textview) v.findViewById(R.id.textView2);
..... // Etc and so on
// Create this listener anywhere, including via making the adapter/class
// implement the listener and passing it in instead
View.OnClickListener listener = new View.OnClickListener(
@Override
public void onClick(View v) {
// Get the view as a TextView, as this will only be used
// with TextViews, so the only view to be passed
// will be Textviews
TextView textView = (TextView) v;
// Do whatever with that text, or however you want to use the view
String text = textView.getText().toString();
someFunction(text);
}
);
textView1.setOnClickListener(listener);
textView2.setOnClickListener(listener);
..... // Etc and so on
现在，如果您需要单击的确切行以及确切 TextView 中的文本，那么您需要使用两个监听器 [即 ListView 上的一个和 TextView 上的一个] 来获取适当的数据。
编辑希望最终:
public class TestAdapter extends BaseAdapter {
Context mContext;
public TestAdapter (Context context, Data someData) {
this.mContext = context;
// Set up the data for your listView however
}
@Override
public int getCount() {
return howManyRows;
}
@Override
public Object getItem(int position) {
return objectAtPosition;
}
@Override
public long getItemId(int position) {
return 0;
} // Unnecessary, unless using databases
// The listener for the textViews, feel free to use different listeners
View.OnClickListener TextViewListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
// Get the view as a TextView, as this will only be used
// with TextViews, so the only view to be passed
// will be Textviews
TextView textView = (TextView) v;
// Do whatever with that text, or however you want to use the view
String text = textView.getText().toString();
someFunction(text);
}
};
// Using the efficient pattern for recycling the views rather than using
// findViewById repeatedly
public static class ViewHolder{
public TextView textView1;
public TextView textView2;
public TextView textView3;
public TextView textView4;
// And any other view that's part of the row view that you need
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = null;
ViewHolder holder;
if(convertView == null) {
// Then gotta set up this row for the first time
LayoutInflater inflater =
(LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.row_layout.xml, parent, false);
// Create a ViewHolder to save all the different parts of the row
holder = new ViewHolder();
holder.textView1 = (TextView) row.findViewById(R.id.textView1);
holder.textView2 = (TextView) row.findViewById(R.id.textView2);
holder.textView3 = (TextView) row.findViewById(R.id.textView3);
holder.textView4 = (TextView) row.findViewById(R.id.textView4);
// Make the row reuse the ViewHolder
row.setTag(holder);
}
else { // Otherwise, use the recycled view
row = convertView;
holder = (ViewHolder) row.getTag();
}
// Set the current row's Textview onClickListeners
// Note: You MAY be able to only set these once- feel free to set that
holder.textView1.setOnClickListener(TextViewListener);
holder.textView2.setOnClickListener(TextViewListener);
holder.textView3.setOnClickListener(TextViewListener);
holder.textView4.setOnClickListener(TextViewListener);
// Set up the rest of the views however you need
/*.....
......
*/
return row;
}
}
关于java - Android中如何从ListView和Adapter中获取选中的文本？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/26519573/