Android 带有自定义对象的自定义 ArrayAdapter
Android custom ArrayAdapter with custom object
我是 Android 开发的新手。
我试图在 Android Studio 中实现自定义 ArrayAdapter
来接受自定义对象。
我参考了一些教程的源代码,但是我的屏幕输出不正确,自定义对象只填充了TextView
,其中link和textViewResourceId
15=] ,而不是自定义对象的属性适当地填写布局中的所有 EditText
。
我试图删除 ArrayAdapter
的构造函数中的 textViewResourceId
参数来解决问题,但 Android Studio 返回错误 - 您必须提供资源 ID对于 TextView
我想要自定义对象的属性全填EditText
并且不返回任何错误信息,谁能给我提示?
这是我的布局:
row_layout.xml
<?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="match_parent">
<TextView
android:id="@+id/row_id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"/>
<EditText
android:id="@+id/row_no"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_margin="1dp"
android:layout_gravity="center_horizontal"
android:background="@color/colorWhite"/>
<EditText
android:id="@+id/row_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_margin="1dp"
android:layout_gravity="center_horizontal"
android:background="@color/colorWhite"/>
</LinearLayout>
这是我的自定义对象:
Row.java
public class Row
{
public int RowNo;
public String RowText;
public Row(int no, String text)
{
this.RowNo = no;
this.RowText = text;
}
}
这是我的自定义 ArrayAdapter:
RowAdapter.java
public class RowAdapter extends ArrayAdapter<Row> {
private final Activity _context;
private final ArrayList<Row> rows;
static class ViewHolder
{
EditText RowNo;
EditText RowText;
}
public RowAdapter(Activity context, ArrayList<Row> rows)
{
super(context,R.layout.row_layout, R.id.row_id ,rows);
this._context = context;
this.rows = rows;
}
public View GetView(int position, View convertView, ViewGroup parent){
ViewHolder holder = null;
if(convertView == null)
{
LayoutInflater inflater = _context.getLayoutInflater();
convertView = inflater.inflate(R.layout.row_layout,parent,false);
holder = new ViewHolder();
holder.RowNo = (EditText)convertView.findViewById(R.id.row_no);
holder.RowText = (EditText)convertView.findViewById(R.id.row_text);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.RowNo.setText(rows.get(position).RowNo);
holder.RowText.setText(rows.get(position).RowText);
return convertView;
}
}
这是我的 Activity class:
RowActivity.java
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.row_list_page);
listView = (ListView)findViewById(R.id.list_view);
ArrayList<Row> rows = new ArrayList<Row>();
rows.add(new Row(1,"Test"));
rows.add(new Row(2,"Test"));
rows.add(new Row(3"Test"));
RowAdapter adapter = new RowAdapter(this,rows);
listView.setAdapter(adapter);
}
public View getView (int position, View convertView, ViewGroup parent)
调用此方法获取视图对象。
在您的代码中有 GetView
,而不是 getView
更改为以下代码:-
RowAdapter.java
public class RowAdapter extends BaseAdapter {
private final Context _context;
private final ArrayList<Row> rows;
public RowAdapter(Context context, ArrayList<Row> rows)
{
this._context = context;
this.rows = rows;
}
@Override
public int getCount() {
return rows.size();
}
@Override
public Object getItem(int position) {
return rows;
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater = (LayoutInflater) _context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView=inflater.inflate(R.layout.row_layout, null,true);
EditText RowNo = (EditText) rowView.findViewById(R.id.row_no);
EditText RowText = (EditText) rowView.findViewById(R.id.row_text);
RowNo.setText(rows.get(position).RowNo);
RowText.setText(rows.get(position).RowText);
return rowView;
}
}
改变你的
public View GetView(int position, View convertView, ViewGroup parent)
与
@Override
public View getView(int position, View convertView, ViewGroup parent)
和
holder.RowNo.setText(rows.get(position).RowNo);
与
holder.RowNo.setText(""+rows.get(position).RowNo);
这是有效的适配器代码
public class RowAdapter extends ArrayAdapter<Row> {
private final Activity _context;
private final ArrayList<Row> rows;
public class ViewHolder
{
EditText RowNo;
EditText RowText;
}
public RowAdapter(Activity context, ArrayList<Row> rows)
{
super(context,R.layout.row_layout, R.id.row_id ,rows);
this._context = context;
this.rows = rows;
}
@Override
public View getView(int position, View convertView, ViewGroup parent){
ViewHolder holder = null;
if(convertView == null)
{
LayoutInflater inflater = _context.getLayoutInflater();
convertView = inflater.inflate(R.layout.row_layout,parent,false);
holder = new ViewHolder();
holder.RowNo = (EditText)convertView.findViewById(R.id.row_no);
holder.RowText = (EditText)convertView.findViewById(R.id.row_text);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.RowNo.setText(""+rows.get(position).RowNo);
holder.RowText.setText(rows.get(position).RowText);
return convertView;
}
}
您在 holder.RowNo.setText(rows.get(position).RowNo);
所以将其替换为
holder.RowNo.setText(""+rows.get(位置).RowNo);
我是 Android 开发的新手。
我试图在 Android Studio 中实现自定义 ArrayAdapter
来接受自定义对象。
我参考了一些教程的源代码,但是我的屏幕输出不正确,自定义对象只填充了TextView
,其中link和textViewResourceId
15=] ,而不是自定义对象的属性适当地填写布局中的所有 EditText
。
我试图删除 ArrayAdapter
的构造函数中的 textViewResourceId
参数来解决问题,但 Android Studio 返回错误 - 您必须提供资源 ID对于 TextView
我想要自定义对象的属性全填EditText
并且不返回任何错误信息,谁能给我提示?
这是我的布局:
row_layout.xml
<?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="match_parent">
<TextView
android:id="@+id/row_id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"/>
<EditText
android:id="@+id/row_no"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_margin="1dp"
android:layout_gravity="center_horizontal"
android:background="@color/colorWhite"/>
<EditText
android:id="@+id/row_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_margin="1dp"
android:layout_gravity="center_horizontal"
android:background="@color/colorWhite"/>
</LinearLayout>
这是我的自定义对象:
Row.java
public class Row
{
public int RowNo;
public String RowText;
public Row(int no, String text)
{
this.RowNo = no;
this.RowText = text;
}
}
这是我的自定义 ArrayAdapter:
RowAdapter.java
public class RowAdapter extends ArrayAdapter<Row> {
private final Activity _context;
private final ArrayList<Row> rows;
static class ViewHolder
{
EditText RowNo;
EditText RowText;
}
public RowAdapter(Activity context, ArrayList<Row> rows)
{
super(context,R.layout.row_layout, R.id.row_id ,rows);
this._context = context;
this.rows = rows;
}
public View GetView(int position, View convertView, ViewGroup parent){
ViewHolder holder = null;
if(convertView == null)
{
LayoutInflater inflater = _context.getLayoutInflater();
convertView = inflater.inflate(R.layout.row_layout,parent,false);
holder = new ViewHolder();
holder.RowNo = (EditText)convertView.findViewById(R.id.row_no);
holder.RowText = (EditText)convertView.findViewById(R.id.row_text);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.RowNo.setText(rows.get(position).RowNo);
holder.RowText.setText(rows.get(position).RowText);
return convertView;
}
}
这是我的 Activity class:
RowActivity.java
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.row_list_page);
listView = (ListView)findViewById(R.id.list_view);
ArrayList<Row> rows = new ArrayList<Row>();
rows.add(new Row(1,"Test"));
rows.add(new Row(2,"Test"));
rows.add(new Row(3"Test"));
RowAdapter adapter = new RowAdapter(this,rows);
listView.setAdapter(adapter);
}
public View getView (int position, View convertView, ViewGroup parent)
调用此方法获取视图对象。
在您的代码中有 GetView
,而不是 getView
更改为以下代码:-
RowAdapter.java
public class RowAdapter extends BaseAdapter {
private final Context _context;
private final ArrayList<Row> rows;
public RowAdapter(Context context, ArrayList<Row> rows)
{
this._context = context;
this.rows = rows;
}
@Override
public int getCount() {
return rows.size();
}
@Override
public Object getItem(int position) {
return rows;
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater = (LayoutInflater) _context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView=inflater.inflate(R.layout.row_layout, null,true);
EditText RowNo = (EditText) rowView.findViewById(R.id.row_no);
EditText RowText = (EditText) rowView.findViewById(R.id.row_text);
RowNo.setText(rows.get(position).RowNo);
RowText.setText(rows.get(position).RowText);
return rowView;
}
}
改变你的
public View GetView(int position, View convertView, ViewGroup parent)
与
@Override
public View getView(int position, View convertView, ViewGroup parent)
和
holder.RowNo.setText(rows.get(position).RowNo);
与
holder.RowNo.setText(""+rows.get(position).RowNo);
这是有效的适配器代码
public class RowAdapter extends ArrayAdapter<Row> {
private final Activity _context;
private final ArrayList<Row> rows;
public class ViewHolder
{
EditText RowNo;
EditText RowText;
}
public RowAdapter(Activity context, ArrayList<Row> rows)
{
super(context,R.layout.row_layout, R.id.row_id ,rows);
this._context = context;
this.rows = rows;
}
@Override
public View getView(int position, View convertView, ViewGroup parent){
ViewHolder holder = null;
if(convertView == null)
{
LayoutInflater inflater = _context.getLayoutInflater();
convertView = inflater.inflate(R.layout.row_layout,parent,false);
holder = new ViewHolder();
holder.RowNo = (EditText)convertView.findViewById(R.id.row_no);
holder.RowText = (EditText)convertView.findViewById(R.id.row_text);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.RowNo.setText(""+rows.get(position).RowNo);
holder.RowText.setText(rows.get(position).RowText);
return convertView;
}
}
您在 holder.RowNo.setText(rows.get(position).RowNo);
所以将其替换为
holder.RowNo.setText(""+rows.get(位置).RowNo);