Java 理解EclipseIDE中的日志Cat错误
我正在制作一个android应用程序，每次尝试运行我的应用程序时都会出现一些错误 我读过一些关于Java中空指针异常的资料，但实际上无法实现任何解决方案 我的代码中似乎有一个bug需要纠正 供您参考，我的日志中有以下错误：Java 理解EclipseIDE中的日志Cat错误,java,php,android,json,parsing,Java,Php,Android,Json,Parsing,我正在制作一个android应用程序，每次尝试运行我的应用程序时都会出现一些错误 我读过一些关于Java中空指针异常的资料，但实际上无法实现任何解决方案 我的代码中似乎有一个bug需要纠正 供您参考，我的日志中有以下错误： 03-07 18:42:27.562: W/dalvikvm(631): threadid=1: thread exiting with uncaught exception (group=0x40014760) 03-07 18:42:27.582: E/AndroidRu
03-07 18:42:27.562: W/dalvikvm(631): threadid=1: thread exiting with uncaught exception (group=0x40014760)
03-07 18:42:27.582: E/AndroidRuntime(631): FATAL EXCEPTION: main
03-07 18:42:27.582: E/AndroidRuntime(631): java.lang.NullPointerException
03-07 18:42:27.582: E/AndroidRuntime(631): at com.fokrul.justdeals.ActivityTab$BooksAdapter.getView(ActivityTab.java:1453)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.AbsListView.obtainView(AbsListView.java:1970)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.ListView.makeAndAddView(ListView.java:1756)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.ListView.fillDown(ListView.java:656)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.ListView.fillFromTop(ListView.java:716)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.ListView.layoutChildren(ListView.java:1595)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.AbsListView.onLayout(AbsListView.java:1800)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.RelativeLayout.onLayout(RelativeLayout.java:912)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.FrameLayout.onLayout(FrameLayout.java:400)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1542)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1403)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.onLayout(LinearLayout.java:1314)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.FrameLayout.onLayout(FrameLayout.java:400)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.RelativeLayout.onLayout(RelativeLayout.java:912)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.FrameLayout.onLayout(FrameLayout.java:400)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1542)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1403)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.LinearLayout.onLayout(LinearLayout.java:1314)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.widget.FrameLayout.onLayout(FrameLayout.java:400)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.View.layout(View.java:9581)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewGroup.layout(ViewGroup.java:3877)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewRoot.performTraversals(ViewRoot.java:1282)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.view.ViewRoot.handleMessage(ViewRoot.java:2040)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.os.Handler.dispatchMessage(Handler.java:99)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.os.Looper.loop(Looper.java:132)
03-07 18:42:27.582: E/AndroidRuntime(631): at android.app.ActivityThread.main(ActivityThread.java:4123)
03-07 18:42:27.582: E/AndroidRuntime(631): at java.lang.reflect.Method.invokeNative(Native Method)
03-07 18:42:27.582: E/AndroidRuntime(631): at java.lang.reflect.Method.invoke(Method.java:491)
03-07 18:42:27.582: E/AndroidRuntime(631): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
03-07 18:42:27.582: E/AndroidRuntime(631): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
03-07 18:42:27.582: E/AndroidRuntime(631): at dalvik.system.NativeStart.main(Native Method)
// to get a View that displays the data at the specified position in the data set.
public View getView(int position, View convertView, ViewGroup parent) {
PromotionsHolder holder;
if(convertView == null){
convertView = inflater.inflate(R.layout.item_product, null);
holder = new PromotionsHolder();
holder.imgImage = (ImageView)convertView.findViewById(R.id.imgImage);
holder.imgImage.getLayoutParams().height = 80;
holder.imgImage.getLayoutParams().width = 80;
holder.tvName = (TextView)convertView.findViewById(R.id.tvName);
holder.tvTitle = (TextView)convertView.findViewById(R.id.tvTitle);
holder.tvPrice = (TextView)convertView.findViewById(R.id.tvPrice);
convertView.setTag(holder);
}else{
holder = (PromotionsHolder)convertView.getTag();
}
Bitmap bmp = BitmapFactory.decodeFile(soImage.get(position));
holder.imgImage.setImageBitmap(bmp);
holder.tvTitle.setText(soTitle.get(position));
((TextView) holder.tvCode).setText(soCode.get(position));
holder.tvPrice.setText(soPrice.get(position));
return convertView;
}
}
private static class ProductsHolder{
ImageView imgImage;
TextView tvCode, tvPrice, tvTitle;
}
private class BooksAdapter extends BaseAdapter{
private LayoutInflater inflater;
private ArrayList<String> list;
public BooksAdapter(ArrayList<String> ll){
inflater = (LayoutInflater)ActivityTab.this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
list = ll;
}
//number of items in the data set are linked by this Adapter.
public int getCount() {
return list.size();
}
// to get data item associated with the specified position in the data set.
public Object getItem(int position) {
return list.get(position);
}
// to get the row id associated with the specified position in the list.
public long getItemId(int position) {
return position;
}
// to get a View that displays the data at the specified position in the data set.
public View getView(int position, View convertView, ViewGroup parent) {
ProductsHolder holder;
if(convertView == null){
convertView = inflater.inflate(R.layout.item_product, null);
holder = new ProductsHolder();
holder.imgImage = (ImageView)convertView.findViewById(R.id.imgImage);
holder.imgImage.getLayoutParams().height = 80;
holder.imgImage.getLayoutParams().width = 80;
holder.tvCode = (TextView)convertView.findViewById(R.id.tvCode);
holder.tvTitle = (TextView)convertView.findViewById(R.id.tvTitle);
holder.tvPrice = (TextView)convertView.findViewById(R.id.tvPrice);
convertView.setTag(holder);
}else{
holder = (ProductsHolder)convertView.getTag();
}
Bitmap bmp = BitmapFactory.decodeFile(bImage.get(position));
holder.imgImage.setImageBitmap(bmp);
holder.tvTitle.setText(bTitle.get(position)); <----Line 1453
holder.tvCode.setText(bCode.get(position));
holder.tvPrice.setText(bPrice.get(position));
return convertView;
}
}
//获取在数据集中指定位置显示数据的视图。
公共视图getView（int位置、视图转换视图、视图组父视图）{
提拔持票人；
if（convertView==null）{
convertView=充气机。充气（R.layout.item_产品，空）；
holder=新的促销文件夹（）；
holder.imgImage=（ImageView）convertView.findViewById（R.id.imgImage）；
holder.imgImage.getLayoutParams（）.height=80；
holder.imgImage.getLayoutParams（）.width=80；
holder.tvName=（TextView）convertView.findViewById（R.id.tvName）；
holder.tvTitle=（TextView）convertView.findViewById（R.id.tvTitle）；
holder.tvPrice=（TextView）convertView.findViewById（R.id.tvPrice）；
convertView.setTag（支架）；
}否则{
holder=（PromotionsHolder）convertView.getTag（）；
}
位图bmp=BitmapFactory.decodeFile（soImage.get（position））；
holder.imgImage.setImageBitmap（bmp）；
holder.tvTitle.setText（soTitle.get（position））；
（（TextView）holder.tvCode）.setText（soCode.get（position））；
holder.tvPrice.setText（soPrice.get（position））；
返回视图；
}
}
私有静态类ProductsHolder{
图像视图图像；
TextView tvCode、tvPrice、tvTitle；
}
私有类适配器扩展了BaseAdapter{
私人充气机；
私有数组列表；
公共BooksAdapter（ArrayList ll）{
充气器=（LayoutFlater）活动选项卡。this.getSystemService（Context.LAYOUT\u充气器\u服务）；
list=ll；
}
//此适配器链接数据集中的项目数。
public int getCount（）{
返回list.size（）；
}
//获取与数据集中指定位置关联的数据项。
公共对象getItem（int位置）{
返回列表。获取（位置）；
}
//获取与列表中指定位置关联的行id。
公共长getItemId（int位置）{
返回位置；
}
//获取在数据集中指定位置显示数据的视图。
公共视图getView（int位置、视图转换视图、视图组父视图）{
产品支架；
if（convertView==null）{
convertView=充气机。充气（R.layout.item_产品，空）；
holder=新产品SHOLDER（）；
holder.imgImage=（ImageView）convertView.findViewById（R.id.imgImage）；
holder.imgImage.getLayoutParams（）.height=80；
holder.imgImage.getLayoutParams（）.width=80；
holder.tvCode=（TextView）convertView.findViewById（R.id.tvCode）；
holder.tvTitle=（TextView）convertView.findViewById（R.id.tvTitle）；
holder.tvPrice=（TextView）convertView.findViewById（R.id.tvPrice）；
convertView.setTag（支架）；
}否则{
holder=（ProductsHolder）convertView.getTag（）；
}
位图bmp=BitmapFactory.decodeFile（bImage.get（position））；
holder.imgImage.setImageBitmap（bmp）；
holder.tvTitle.setText（bTitle.get（position））；
NullPointerException的原因
当任何对象包含null并且您试图访问它时，就会发生这种情况
例如
String str = null;
Log.v("App",str);
检查ActivityTab.java:1453。在本例中，它发生在这一行。添加java代码：）太好了。在这一行中发现了一些问题。但我的应用程序在运行时就崩溃了。我认为threadid=1：线程退出时出现未捕获的异常（组=0x40014760）
造成了重大问题？您解决了第1453行出现的NPE问题了吗？如果有任何错误，请告诉我logcat。是的。我解决了，现在它出现在第1454行。@TirathSingh您能告诉我它在第1454行写了什么吗。工作非常顺利。整理好了；XML文件中有一个用不同名称定义的东西。谢谢谢谢你的帮助：）