我正在开发一个应用程序,它显示一个包含 30 个项目的 ListView。在每一行中,应该有一个文本和一个图像。我搜索不同的教程,但不幸的是,它们都不适合我。所以我请你看一下我的代码并告诉我那里出了什么问题,因为当我启动应用程序时,ListView 是空的。
mainActivity.java:
setContentView(R.layout.auswertung);
ListView list = (ListView) findViewById(R.id.listView1);
list.setAdapter(new MyListAdapter(this, fragen));
MyListAdapter.java
import java.util.ArrayList;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class MyListAdapter extends ArrayAdapter<Frage>{
private final Context context;
private ArrayList<Frage> fragen;
public MyListAdapter(Context context, ArrayList<Frage> f) {
super(context, R.layout.reihe);
this.context = context;
fragen = f;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View rowView = convertView;
if(rowView == null)
{
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rowView = inflater.inflate(R.layout.reihe, parent, false);
}
TextView textView = (TextView) rowView.findViewById(R.id.textView4);
ImageView imageView = (ImageView) rowView.findViewById(R.id.img1);
textView.setText("Frage " + (position+1));
if (fragen.get(position).getRichtig()==true)
{
imageView.setImageResource(R.drawable.richtig);
}
else
{
imageView.setImageResource(R.drawable.falsch);
}
return rowView;
}
}
auswertung.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="0.96"
android:background="@drawable/hintergrund"
android:orientation="vertical" >
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="35dp"
android:layout_marginTop="19dp"
android:text="Auswertung"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#000000" />
<ListView
android:id="@+id/listView1"
android:layout_width="fill_parent"
android:layout_height="460dp"
android:layout_marginTop="60dp">
</ListView>
</RelativeLayout>
reihe.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:paddingTop="4dip"
android:paddingBottom="6dip"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView android:id="@+id/textView4"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="5"
android:textSize="16dp"
android:textColor="#000000" />
<ImageView
android:id="@+id/img1"
android:layout_width="25dp"
android:layout_height="25dp" />
</LinearLayout>
如您所见,我有一个背景图像,并且还想问您,如何使 ListView 的背景不可见,以便我可以看到文本和图像后面的背景?