问题描述

Volley请求数据遇到问题，显示空指针

我用Volley请求数据传给了，而且Log也有数据，但是当我想用settext()把数据传进去，却显示空指针，而我要是把settext放在点击事件里面，就可以显示处理，求助这是怎么回事

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
getDataFromNet();
initData();

}

private void initData() {
//tv.setMovementMethod(ScrollingMovementMethod.getInstance());// 滚动

tv.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Spanned spanned = Html.fromHtml(html, new Html.ImageGetter() {
@Override
public Drawable getDrawable(String source) {
InputStream is = null;
try {
is = (InputStream) new URL(source).getContent();
Drawable d = Drawable.createFromStream(is, null);
d.setBounds(0, 0, d.getIntrinsicWidth(),
d.getIntrinsicHeight());
is.close();
return d;
} catch (Exception e) {
return null;
}
}

}
, null);

tv.setText(spanned);
}

}

);

}

private void initView() {
tv = (TextView) findViewById(R.id.tv);
}

private void getDataFromNet() {
RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
StringRequest request = new StringRequest(Request.Method.POST, url, new Response.Listener() {
@Override
public void onResponse(String s) {
Log.i("aa", "post请求成功" + s);
Toast.makeText(MainActivity.this, s, Toast.LENGTH_LONG).show();
/**

• 解析数据
  */
  processData(s);
  }
  }, new Response.ErrorListener() {
  @Override
  public void onErrorResponse(VolleyError volleyError) {
  Log.i("aa", "post请求失败" + volleyError.toString());
  Toast.makeText(MainActivity.this, volleyError.toString(), Toast.LENGTH_LONG).show();
  }
  }) {
  @Override
  protected Map getParams() throws AuthFailureError {
  HashMap map = new HashMap<>();
  map.put("contentid", "567210bd5d774358778b4c51");
  map.put("client", "2");
  return map;
  }

  };

  requestQueue.add(request);

  }

  private Bean.DData ddata;

  private void processData(String s) {
  final Bean data = Bean.getData(s);
  ddata = data.data;

  html = ddata.html;

  }

}

这样是没问题的。

public class MainActivity extends AppCompatActivity {
private TextView tv;
private String url = "http://api2.pianke.me/article/info";
String html;
Spanned spanned;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initView();
    getDataFromNet();
    initData();
    tv.setText(spanned);

}

private void initData() {
    //tv.setMovementMethod(ScrollingMovementMethod.getInstance());// 滚动

    spanned = Html.fromHtml(html, new Html.ImageGetter() {
        @Override
        public Drawable getDrawable(String source) {
            InputStream is = null;
            try {
                is = (InputStream) new URL(source).getContent();
                Drawable d = Drawable.createFromStream(is, null);
                d.setBounds(0, 0, d.getIntrinsicWidth(),
                        d.getIntrinsicHeight());
                is.close();
                return d;
            } catch (Exception e) {
                return null;
            }
        }

    }
            , null);

}

private void initView() {
    tv = (TextView) findViewById(R.id.tv);
}

private void getDataFromNet() {
    RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
    StringRequest request = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
        @Override
        public void onResponse(String s) {
            Log.i("aa", "post请求成功" + s);
            Toast.makeText(MainActivity.this, s, Toast.LENGTH_LONG).show();
            /**
             * 解析数据
             */
            processData(s);
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError volleyError) {
            Log.i("aa", "post请求失败" + volleyError.toString());
            Toast.makeText(MainActivity.this, volleyError.toString(), Toast.LENGTH_LONG).show();
        }
    }) {
        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            HashMap<String, String> map = new HashMap<>();
            map.put("contentid", "567210bd5d774358778b4c51");
            map.put("client", "2");
            return map;
        }

    };

    requestQueue.add(request);

}

private Bean.DData ddata;

private void processData(String s) {
    final Bean data = Bean.getData(s);
    ddata = data.data;

    html = ddata.html;

}

}

但是这样就报空指针，请教各位

解决方案

http://www.ithao123.cn/content-7139912.html

解决方案二：

贴一下代码吧，最好一步一步调试一下试试，另外检查一下是不是把请求加入到了RequestQueue的队列里面去.