volley 请求数据给控件赋值

我把这句放到回调的response里怎么就可以赋上值了，这是什么原因
txtBorrower = = (TextView) findViewById(R.id.txtBorrower);

这是什么赋值的写法？==不是判断是否等于么
txtBorrower = = (TextView) findViewById(R.id.txtBorrower);

就是把这句放到回调函数里赋值就没事了
txtBorrower = = (TextView) findViewById(R.id.txtBorrower);
如果放到onCreate里报错内容为：

你确定能在onResponse方法里面能用findViewById()？
把这一句拿出来分开写，看看有没有哪个是null
arr.getJSONObject(0).getString("borrower")

我都调试通了已经赋上值了，就是不知道为啥要放里面，如果初始化的时候findById总是null,我就不明白这块

在onCreate()里面findViewById肯定不会错的，应该是其他问题，你把错误时的代码、错误日志和现在正确的代码贴出来看看，行号也截进图去

package com.main.museumarchives;import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;import android.app.Activity;
import android.app.ProgressDialog;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.TranslateAnimation;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;
import com.tools.ReadConfig;public class MainDetailActivity extends Activity {
// ViewPager是google SDk中自带的一个附加包的一个类，可以用来实现屏幕间的切换。
// android-support-v4.jar
private ViewPager mPager;//页卡内容
private List<View> listViews; // Tab页面列表
private ImageView cursor;// 动画图片
private TextView tabBorrowDeatil, tabBorrower, tabApproval;// 页卡头标
private int offset = 0;// 动画图片偏移量
private int currIndex = 0;// 当前页卡编号
private int bmpW;// 动画图片宽度 private HashMap<String, String>session;
private RequestQueue requestQueue; // 请求队列对象
private ProgressDialog pd; private TextView txtObjID; // 借阅审批表主键
private TextView txtBorrower; // 借阅人
private TextView txtBorrowDate; // 借阅日期
private TextView txtBorrowType; // 借阅方式
private TextView txtBorrowRe; // 借阅说明

private TextView txtOperator; // 经办人
private TextView txtApprovalDate; // 审批时间
private TextView txtApprovalRe; // 审批说明

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_detail);
InitImageView();
InitTabTextView();
InitViewPager();
requestQueue = Volley.newRequestQueue(this);
session = (HashMap<String, String>) this.getIntent()
.getBundleExtra("session").getSerializable("sessionid");
String username = session.get("username");
String objid = session.get("objid");
String descriptionfilesobjid = session.get("descriptionfilesobjid");
String descriptionfilesdetailobjid = session.get("descriptionfilesdetailobjid");

InitDate(username, objid, descriptionfilesobjid, descriptionfilesdetailobjid);
} /**
* 初始化头标
*/
private void InitTabTextView() {
tabBorrowDeatil = (TextView) findViewById(R.id.tabBorrowDeatil);
tabBorrower = (TextView) findViewById(R.id.tabBorrower);
tabApproval = (TextView) findViewById(R.id.tabApproval); tabBorrowDeatil.setOnClickListener(new MyOnClickListener(0));
tabBorrower.setOnClickListener(new MyOnClickListener(1));
tabApproval.setOnClickListener(new MyOnClickListener(2));
}

/**
* 初始化各表头中的控件
* */
private void InitTextView(){
// 借阅信息--控件
txtObjID = (TextView) findViewById(R.id.txtObjID);
txtBorrower = (TextView) findViewById(R.id.txtBorrower);
txtBorrowDate = (TextView) findViewById(R.id.txtBorrowDate);
txtBorrowType = (TextView) findViewById(R.id.txtBorrowType);
txtBorrowRe = (TextView) findViewById(R.id.txtBorrowRe);
// 审批信息--控件
txtOperator = (TextView) findViewById(R.id.txtOperator);
txtApprovalDate = (TextView) findViewById(R.id.txtApprovalDate);
txtApprovalRe = (TextView) findViewById(R.id.txtApprovalRe);
} /**
* 初始化ViewPager
*/
private void InitViewPager() {
mPager = (ViewPager) findViewById(R.id.vPager);
listViews = new ArrayList<View>();
LayoutInflater mInflater = getLayoutInflater();
listViews.add(mInflater.inflate(R.layout.main_detail_borrowdetail, null));
listViews.add(mInflater.inflate(R.layout.main_detail_borrower, null));
listViews.add(mInflater.inflate(R.layout.main_detail_approval, null));
mPager.setAdapter(new MyPagerAdapter(listViews));
mPager.setCurrentItem(0);
mPager.setOnPageChangeListener(new MyOnPageChangeListener());
} /**
* 初始化动画
*/
private void InitImageView() {
cursor = (ImageView) findViewById(R.id.cursor);
bmpW = BitmapFactory.decodeResource(getResources(), R.drawable.decline)
.getWidth();// 获取图片宽度
DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int screenW = dm.widthPixels;// 获取分辨率宽度
offset = (screenW / 3 - bmpW) / 2;// 计算偏移量
Matrix matrix = new Matrix();
matrix.postTranslate(offset, 0);
cursor.setImageMatrix(matrix);// 设置动画初始位置
} /**
* 初始化数据
* */
private void InitDate(String username, String objid,String descriptionfilesobjid,String descriptionfilesdetailobjid){
InitTextView();
pd = ProgressDialog.show(MainDetailActivity.this, "", "数据加载中，请稍后……");

// 审批页面赋值
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
txtOperator.setText(username.toString());
txtApprovalDate.setText(sdf.format(new Date()));
// 借阅信息页面赋值
// 服务端验证
String strUrl = ReadConfig.getPropertiesURL() + "/DASys/UI/WH_DescriptionApproval/AndroidDescriptionApprovalPrimaryKey.jsp?objid="+objid;
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(
Request.Method.GET, strUrl,
null, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
// TODO Auto-generated method stub
try {
JSONObject result = new JSONObject(response.toString()); //转换为JSONObject
JSONArray arr = result.getJSONArray("rows"); //获取JSONArray
if(arr.length() > 0){
txtObjID.setText(arr.getJSONObject(0).getString("objid"));
txtBorrower.setText(arr.getJSONObject(0).getString("borrower"));
txtBorrowDate.setText(arr.getJSONObject(0).getString("borrowstartdate") + " 至 " + arr.getJSONObject(0).getString("borrowenddate"));
txtBorrowType.setText(arr.getJSONObject(0).getString("borrowtypename"));
txtBorrowRe.setText(arr.getJSONObject(0).getString("borrowre"));

pd.dismiss();// 关闭ProgressDialog
}else{
pd.dismiss();// 关闭ProgressDialog
Toast.makeText(MainDetailActivity.this, "数据加载失败!", Toast.LENGTH_SHORT).show();
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
pd.dismiss();// 关闭ProgressDialog
Toast.makeText(MainDetailActivity.this, "数据加载失败!", Toast.LENGTH_SHORT).show();
}
}
},
new Response.ErrorListener(){
@Override
public void onErrorResponse(VolleyError error) {
// TODO Auto-generated method stub
pd.dismiss();// 关闭ProgressDialog
Toast.makeText(MainDetailActivity.this, "数据加载失败!", Toast.LENGTH_SHORT).show();
}
});
requestQueue.add(jsonObjectRequest);
} /**
* ViewPager适配器
*/
public class MyPagerAdapter extends PagerAdapter {
public List<View> mListViews; public MyPagerAdapter(List<View> mListViews) {
this.mListViews = mListViews;
} @Override
public void destroyItem(View arg0, int arg1, Object arg2) {
((ViewPager) arg0).removeView(mListViews.get(arg1));
} @Override
public void finishUpdate(View arg0) {
} @Override
public int getCount() {
return mListViews.size();
} @Override
public Object instantiateItem(View arg0, int arg1) {
((ViewPager) arg0).addView(mListViews.get(arg1), 0);
return mListViews.get(arg1);
} @Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == (arg1);
} @Override
public void restoreState(Parcelable arg0, ClassLoader arg1) {
} @Override
public Parcelable saveState() {
return null;
} @Override
public void startUpdate(View arg0) {
}
} /**
* 头标点击监听
*/
public class MyOnClickListener implements View.OnClickListener {
private int index = 0; public MyOnClickListener(int i) {
index = i;
} @Override
public void onClick(View v) {
mPager.setCurrentItem(index);
}
}; /**
* 页卡切换监听
*/
public class MyOnPageChangeListener implements OnPageChangeListener { int one = offset * 2 + bmpW;// 页卡1 -> 页卡2 偏移量
int two = one * 2;// 页卡1 -> 页卡3 偏移量 @Override
public void onPageSelected(int arg0) {
Animation animation = null;
/*switch (arg0) {
case 0:
if (currIndex == 1) {
animation = new TranslateAnimation(one, 0, 0, 0);
} else if (currIndex == 2) {
animation = new TranslateAnimation(two, 0, 0, 0);
}
break;
case 1:
if (currIndex == 0) {
animation = new TranslateAnimation(offset, one, 0, 0);
} else if (currIndex == 2) {
animation = new TranslateAnimation(two, one, 0, 0);
}
break;
case 2:
if (currIndex == 0) {
animation = new TranslateAnimation(offset, two, 0, 0);
} else if (currIndex == 1) {
animation = new TranslateAnimation(one, two, 0, 0);
}
break;
}*/
animation = new TranslateAnimation(one*currIndex, one*arg0, 0, 0);
currIndex = arg0;
animation.setFillAfter(true);// True:图片停在动画结束位置
animation.setDuration(300);
cursor.startAnimation(animation);
} @Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
} @Override
public void onPageScrollStateChanged(int arg0) {
}
}
}

少写了一句
InitTextView() 把这个方法放到onCreate()的InitDate();前面

我把这句放到回调的response里怎么就可以赋上值了，这是什么原因
txtBorrower = = (TextView) findViewById(R.id.txtBorrower);这个可能需要看你更多的代码，理论上说，你是在一个activity里调用的话，都应该是调用的当前activity的findViewById方法，find的是加载到当前window的view，只要是在setcontentview后调用，效果应该是一样的。

我把这句放到回调的response里怎么就可以赋上值了，这是什么原因
txtBorrower = = (TextView) findViewById(R.id.txtBorrower);这个可能需要看你更多的代码，理论上说，你是在一个activity里调用的话，都应该是调用的当前activity的findViewById方法，find的是加载到当前window的view，只要是在setcontentview后调用，效果应该是一样的。
代码已经发了，帮忙看看

错误日志显示在151行空指针，说明你initData时那个TextView txtOperator还没初始化

或者是username没取到值，是null

话说你username本来就是String,还来个toString干啥

username是前面activity传过来的值，现在值都有，你能给我个邮箱吗？我做了个例子你帮我瞧瞧，行不

应该把每个页面加载的控件放到对应的这里面；控件与页面同时初始化
/**
         * 初始化ViewPager
         */
        private void InitViewPager() {}

调试易

volley 请求数据给控件赋值

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