Android gridview 空指针

vh.imageViewvh.setImageResource(getItem(i).dataicon);
vh.textViewvh.setText(getItem(i).dataName);
//问题出在这里，这两句都是空指针
package com.zhangyi.zyapp26_27;
import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.ViewSwitcher;
import java.util.ArrayList;
/**
* Created by me on 2016-11-3.
*/
public class BViewSwitcher extends Activity {
public static final int NUMBER_PER_SCREEN = 12;
public static class DataItem{
public String dataName;
public int dataicon;
}
static class ViewHolder{
ImageView imageViewvh;
TextView textViewvh;
}
private ArrayList<DataItem> items = new ArrayList<>();
private int screenNo = 1;
private int screenCount;
ViewSwitcher myviewswitcher;
LayoutInflater inflater;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.b_viewswitcher);
inflater = LayoutInflater.from(BViewSwitcher.this);
for (int i = 0; i < 40; i++) {
String dataname ="";
int drawable =0;
DataItem item=new DataItem();
switch ((int) (Math.random() * 3)) {
case 0:dataname="Chrome "+i;drawable = R.mipmap.ic_launcher2;break;
case 1:dataname="Picture "+i;drawable = R.mipmap.ic_launcher3;break;
case 2:dataname="Shop "+i;drawable = R.mipmap.ic_launcher4;break;
}
item.dataName = dataname;
item.dataicon = drawable;
items.add(item);
}
screenCount = items.size() % NUMBER_PER_SCREEN == 0 ?
items.size() / NUMBER_PER_SCREEN : items.size() / NUMBER_PER_SCREEN + 1;
myviewswitcher = (ViewSwitcher) findViewById(R.id.myviewswitcher);
myviewswitcher.setFactory(new ViewSwitcher.ViewFactory() {
@Override
public View makeView() {
return inflater.inflate(R.layout.datagridview, null);
}
});
next(null);
}
public void previous(View view) {
if (screenNo > 1) {
screenNo--;
myviewswitcher.setInAnimation(this, R.anim.push_left_in);
((GridView) myviewswitcher.getNextView()).setAdapter(adapter);
myviewswitcher.showPrevious();
}
}
public void next(View view) {
if (screenNo < screenCount) {
screenNo++;
myviewswitcher.setInAnimation(this, R.anim.push_right_in);
((GridView) myviewswitcher.getNextView()).setAdapter(adapter);
myviewswitcher.showNext();
}
}
private BaseAdapter adapter = new BaseAdapter() {
@Override
public int getCount() {
if (screenNo == screenCount && items.size() % NUMBER_PER_SCREEN != 0) {
return items.size() % NUMBER_PER_SCREEN;
}
return NUMBER_PER_SCREEN;
}
@Override
public DataItem getItem(int i) {
return items.get((screenNo - 1) * NUMBER_PER_SCREEN + i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
View view1 = view;
ViewHolder vh=new ViewHolder();
ViewGroup viewGroup2=(ViewGroup) getLayoutInflater().inflate(R.layout.datagridview, null);
vh.imageViewvh = (ImageView) viewGroup2.findViewById(R.id.imagedata);
vh.textViewvh = (TextView) viewGroup2.findViewById(R.id.textdata);
try {
vh.imageViewvh.setImageResource(getItem(i).dataicon);
vh.textViewvh.setText(getItem(i).dataName);
//问题出在这里，这两句都是空指针
} catch (Exception e) {
e.printStackTrace();
}
// ViewGroup parent1 = (ViewGroup) vh.imageViewvh.getParent();
// if (parent1 != null) {
// parent1.removeAllViews();
// }
//
// ViewGroup parent11 = (ViewGroup) vh.textViewvh.getParent();
// if (parent11 != null) {
// parent11.removeAllViews();
// }
// viewGroup2.addView(vh.imageViewvh);
// viewGroup2.addView(vh.textViewvh);
// if (view1 == null) {
// view1 = inflater.inflate(R.layout.datagridview, viewGroup,false);
// }
// ImageView imageView = (ImageView) viewGroup2.findViewById(R.id.imagedata);
// TextView textView = (TextView) viewGroup2.findViewById(R.id.textdata);
// try {
//
// imageView.setImageResource(getItem(i).dataicon);
// imageView.setImageResource(R.mipmap.ic_launcher2);
// textView.setText(getItem(i).dataName);
// }catch (Exception e){
// e.printStackTrace();
// }
return viewGroup2;
}
};
}