java - 如何从 adapter.java 中的 ListView 设置 Onclick ImageView

Question

我的问题是关于“如何从 ListView 设置 OnClick ImageView”

适配器.java

public class Adapter extends BaseAdapter implements OnClickListener{

    Context context;
    ArrayList<Contact> list;
    LayoutInflater inflater;

    public Adapter(Context context, ArrayList<Contact> list) {
       super();
       this.context = context;
       this.list = list;
       this.inflater = 
       LayoutInflater.from(context);
    }

    public View getView(int arg0, View arg1, ViewGroup arg2) {
        ContactView pv=null;
        if(arg1==null)
        {
           arg1= inflater.inflate(R.layout.additem,  null);
           pv = new ContactView();
           pv.iv=(ImageView) arg1.findViewById(R.id.imageView1);
           pv.name=(TextView) arg1.findViewById(R.id.textView1); 
           pv.number=(CheckedTextView) arg1.findViewById(R.id.checkedTextView1);
           pv.message=(ImageView) arg1.findViewById(R.id.imageView2);
           arg1.setTag(pv); 
       }    
       else 
       {    
           pv=(ContactView) arg1.getTag();
           pv.iv.setImageURI( 
           list.get(arg0).getImage());       
           pv.name.setText( list.get(arg0).getName());
           pv.number.setText( String.valueOf(list.get(arg0).getNumber())); 
           pv.message=(ImageView) 
           arg1.findViewById( R.id.imageView2);
           pv.message.setOnClickListener( this);
           return arg1;
       }
    }

    static class ContactView{
       ImageView iv;
       TextView name;
       CheckedTextView number; 
       ImageView message;
    }
}

当我从 ListView 中设置点击消息(ImageView)时，它说

“致命异常:主要”

“无法启动 Activity ”

"java.lang.NullPointerException"

.
MainActvity.java

ArrayList<Contact> list = new ArrayList<Contact>();
Adapter adapter;
ImageView message;

protected void onCreate(Bundle savedInstanceState) {
    this.lv = (ListView) this.findViewById(R.id.listView1);

    this.adapter=new MyAdapter(this,list);
    this.lv.setAdapter(adapter);

}

public void onClick(View arg0) {
    // TODO Auto-generated method stub 
    Toast.makeText(this, "sample", Toast.LENGTH_SHORT).show();
}

有人可以帮我如何从 ListView 中设置点击消息(ImageView)？？谢谢

Answer 1

我认为你应该在适配器内部设置取消点击...在每个项目上， Activity 在开始时不会找到该 View

有点像

pv.message.setClickable(true);
pv.message.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Toast.makeText(arg0.getContext(), "sample", Toast.LENGTH_SHORT).show();
        }
    });