Question

android 里面我往ListView里面添加数据成功但是ListView里面显示不出来

package com.shopping.android;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import com.shopping.android.R;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
public class Advert extends ShoppingActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.advert);
ListView listview = (ListView) findViewById(R.id.listView1);
List<HashMap<String, Object>> map = new ArrayList<HashMap<String, Object>>();

SimpleAdapter sa = new SimpleAdapter(this, map, R.layout.advert,
new String[] { "img", "text1", "text2" }, new int[] { R.id.ima,
R.id.tv1, R.id.tv2 });
listview.setAdapter(sa);
HashMap<String, Object> hash = new HashMap<String, Object>();
hash.put("img", R.drawable.ic_launcher);
hash.put("text1", "广告1");
hash.put("text2", "广告1广告1广告1");
map.add(hash);

hash = new HashMap<String, Object>();
hash.put("title", "广告2");
hash.put("info", "广告2广告2广告2");
hash.put("img", R.drawable.ic_launcher);
map.add(hash);

hash = new HashMap<String, Object>();
hash.put("title", "广告3");
hash.put("info", "广告3广告3广告3");
hash.put("img", R.drawable.ic_launcher);
map.add(hash);

hash = new HashMap<String, Object>();
hash.put("title", "广告4");
hash.put("info", "广告4广告4广告4");
hash.put("img", R.drawable.ic_launcher);
map.add(hash);
}
}
hash = new HashMap<String, Object>();
hash.put("img", "广告4");
hash.put("text1", "广告4广告4广告4");
hash.put("text2", R.drawable.ic_launcher);
map.add(hash);

SimpleAdapter sa = new SimpleAdapter(this, map, R.layout.advertlist,
new String[] { "img", "text1", "text2" }, new int[] { R.id.ima,
R.id.tv1, R.id.tv2 });

listview.setAdapter(sa);
}
}

放下来了，但是还是只有一条数据啊？求解答

Answer 1

你代码中的setContentView(R.layout.advert),
SimpleAdapter sa = new SimpleAdapter(this, map, R.layout.advert,
new String[] { "img", "text1", "text2" }, new int[] { R.id.ima,
R.id.tv1, R.id.tv2 })
错误应该在SimpleAdapter构造函数中的第3个参数。

public class MainActivity extends Activity {

List<HashMap<String,Object>> listString;
SimpleAdapter simpleAdapter;
ListView listview;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//R.layout.activity_main中含有ListView.
setContentView(R.layout.activity_main);

listString=new ArrayList<HashMap<String,Object>>();

for(int i=1;i<=5;i++){
HashMap<String, Object> map=new HashMap<String, Object>();
map.put("img", R.drawable.png_01);
map.put("text1", "广告"+i);
map.put("text2", "广告"+i+"广告"+i);

listString.add(map);

}

listview=(ListView) findViewById(R.id.listView1);
//R.layout.listview_item.这个指的是ListView中每一项的map,即一行中你显示的imageView,textview1,textview2
//的layout.xml
simpleAdapter=new SimpleAdapter(this, listString, R.layout.listview_item, new String[]{"img","text1","text2"}, new int[]{R.id.imageView1,R.id.TextView1,R.id.TextView2});

listview.setAdapter(simpleAdapter);

}
}

追问

你好，确实是的，之后我把布局文件改过来了，但是我添加了四条数据，运行之后显示的却只有一条，是怎么回事啊

Answer 2

是执行顺序的问题。你把适配器和listview放到最下面就行了！

追问

代码在补充问题里面，希望您帮我看一看

Answer 3

看一下ListView中的Item项的背景颜色是不是和文字的字体颜色设置成一样的了。
如果是一样的那肯定是显示不出来了。

你先把文字颜色设置成为黑色试试。