Android 为什么此自定义适配器不显示输出
我是android新手。我尝试了自定义适配器,但输出不可见。显然没有错误。请告诉我哪里做错了 这是代码Android 为什么此自定义适配器不显示输出,android,Android,我是android新手。我尝试了自定义适配器,但输出不可见。显然没有错误。请告诉我哪里做错了 这是代码 package com.example.customadapter; import android.app.Activity; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Ada
package com.example.customadapter;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;
import android.widget.Toast;
import android.widget.TextView;
public class MainActivity extends Activity {
GridView gridview;
static final String[] Box_Clrs=new String[]{
"pink" , "red" , "blue"
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gridview= (GridView) findViewById(R.id.grid_view);
gridview.setAdapter(new ImageAdapter(this, Box_Clrs));
gridview.setOnItemClickListener(new OnItemClickListener()
{
public void onItemClick(AdapterView<?> parent, View v, int position, long id){
Toast.makeText(
getApplicationContext(),((TextView) v.findViewById(R.id.grid_text))
.getText(), Toast.LENGTH_SHORT).show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
activity_main.xml
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/grid_view"
android:gravity="center"
android:columnWidth="100dp"
android:stretchMode="columnWidth"
android:numColumns="auto_fit"
tools:context="com.example.customadapter.MainActivity" >
mobile.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="5dp"
tools:context="com.example.customadapter.MainActivity" >
<ImageView
android:id="@+id/image"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginRight="10dp"
android:src="@drawable/blue">
</ImageView>
<TextView
android:id="@+id/grid_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dp">
</TextView>
缺少convertView=gridView;在膨胀和填充列表项布局之后。我发现这样做更容易:
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.list_item, parent, false);
}
// do your setup here
return convertView;
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater=(LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE)
View view
if(convertView==null)
{
view = inflater.inflate(R.layout.mobile,parent, false);
} else {
view = convertView;
}
TextView textview=(TextView) view.findViewById(R.id.grid_text);
textview.setText(clrValues[position]);
ImageView imageview=(ImageView) view.findViewById(R.id.image);
String clr= clrValues[position];
if(clr.equals("pink"))
imageview.setImageResource(R.drawable.pink);
else if(clr.equals("red"))
imageview.setImageResource(R.drawable.red);
else
imageview.setImageResource(R.drawable.blue);
return view;
}
试试这个
更改如下
View gridView;
if(convertView==null)
{
gridView = new View(context);
gridView = inflater.inflate(R.layout.mobile,null);
…………
}
到
getView方法应该返回网格视图的项,而不是gridview本身 尝试使用类似以下内容:
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.list_item, parent, false);
}
// do your setup here
return convertView;
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater=(LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE)
View view
if(convertView==null)
{
view = inflater.inflate(R.layout.mobile,parent, false);
} else {
view = convertView;
}
TextView textview=(TextView) view.findViewById(R.id.grid_text);
textview.setText(clrValues[position]);
ImageView imageview=(ImageView) view.findViewById(R.id.image);
String clr= clrValues[position];
if(clr.equals("pink"))
imageview.setImageResource(R.drawable.pink);
else if(clr.equals("red"))
imageview.setImageResource(R.drawable.red);
else
imageview.setImageResource(R.drawable.blue);
return view;
}
您还应该改进方法:
@Override
public Object getItem(int position) {
return clrValues[position];
}
@Override
public long getItemId(int position){
return position;
}
请参阅有关自定义适配器的教程您似乎希望返回gridView而不是convertView