我的适配器
ListAdapter adapter = new SimpleAdapter(this, contactList,
R.layout.news_list_adapter,new String[] {TAG_NAME, TAG_ADDRESS, R.drawable.news_en2},
new int[] {R.id.newsHead, R.id.qisaIzzah ,R.id.newsFontImage});
我有要添加到列表中的位图图像，我可以写什么而不是 R.drawable.news_en2
示例位图
byte[] decodedString = Base64.decode(news.getString("newsimage"),Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString,0,decodedString.length);
通过扩展 BaseAdapter 类，您可以轻松地在 ListView 中添加位图图像
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
// if it's not recycled, initialize some attributes
if (row == null) {
LayoutInflater li = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = li.inflate(R.layout.menucategory, null);
//imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
}
// getCategoryItem
Category category = (Category) getItem(position);
// Get reference to ImageView
categoryIcon = (ImageView) row.findViewById(R.id.category_image);
//categoryIcon.setLayoutParams(new GridView.LayoutParams(85, 85));
categoryIcon.setScaleType(ImageView.ScaleType.CENTER_CROP);
categoryIcon.setPadding(5, 5, 5, 5);
categoryName = (TextView) row.findViewById(R.id.category_name);
//Set category name
categoryName.setText(category.getCategoryName());
if(category.getCategoryPath() != null){
Bitmap bitmap = BitmapFactory.decodeFile(category.getCategoryPath());
System.out.println("bitmap2:: "+ bitmap);
if(bitmap != null){
categoryIcon.setImageBitmap(bitmap);
}
}
return row;
}
您还必须定义一个可以采用位图的布局。在 Mohammod Hossain 发布的上述示例中，R.layout.menucategory 指的是该自定义布局。
基本上，简单的适配器会自动将一些资源 ID 或 URI 绑定到行布局的图像视图。但它不支持位图。
这是一个问题，因为每个不得不管理位图的人都知道，我们经常不得不减小图片的大小以防止出现 OutOfMemory 异常。但是如果你想将图片添加到listView中，如果你只提供URI，你不能减小图片的大小。所以这是解决方案：
我已经修改了 simpleAdapter 以便能够处理位图。将此类添加到您的项目中，并使用它来代替 simpleAdapter。然后，不要传递图像的 URI 或 ressourceId，而是传递 Bitmap ！
下面是代码：
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Checkable;
import android.widget.ImageView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
public class ExtendedSimpleAdapter extends SimpleAdapter{
List<HashMap<String, Object>> map;
String[] from;
int layout;
int[] to;
Context context;
LayoutInflater mInflater;
public ExtendedSimpleAdapter(Context context, List<HashMap<String, Object>> data,
int resource, String[] from, int[] to) {
super(context, data, resource, from, to);
layout = resource;
map = data;
this.from = from;
this.to = to;
this.context = context;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
return this.createViewFromResource(position, convertView, parent, layout);
}
private View createViewFromResource(int position, View convertView,
ViewGroup parent, int resource) {
View v;
if (convertView == null) {
v = mInflater.inflate(resource, parent, false);
} else {
v = convertView;
}
this.bindView(position, v);
return v;
}
private void bindView(int position, View view) {
final Map dataSet = map.get(position);
if (dataSet == null) {
return;
}
final ViewBinder binder = super.getViewBinder();
final int count = to.length;
for (int i = 0; i < count; i++) {
final View v = view.findViewById(to[i]);
if (v != null) {
final Object data = dataSet.get(from[i]);
String text = data == null ? "" : data.toString();
if (text == null) {
text = "";
}
boolean bound = false;
if (binder != null) {
bound = binder.setViewValue(v, data, text);
}
if (!bound) {
if (v instanceof Checkable) {
if (data instanceof Boolean) {
((Checkable) v).setChecked((Boolean) data);
} else if (v instanceof TextView) {
// Note: keep the instanceof TextView check at the bottom of these
// ifs since a lot of views are TextViews (e.g. CheckBoxes).
setViewText((TextView) v, text);
} else {
throw new IllegalStateException(v.getClass().getName() +
" should be bound to a Boolean, not a " +
(data == null ? "<unknown type>" : data.getClass()));
}
} else if (v instanceof TextView) {
// Note: keep the instanceof TextView check at the bottom of these
// ifs since a lot of views are TextViews (e.g. CheckBoxes).
setViewText((TextView) v, text);
} else if (v instanceof ImageView) {
if (data instanceof Integer) {
setViewImage((ImageView) v, (Integer) data);
} else if (data instanceof Bitmap){
setViewImage((ImageView) v, (Bitmap)data);
} else {
setViewImage((ImageView) v, text);
}
} else {
throw new IllegalStateException(v.getClass().getName() + " is not a " +
" view that can be bounds by this SimpleAdapter");
}
}
}
}
}
private void setViewImage(ImageView v, Bitmap bmp){
v.setImageBitmap(bmp);
}
}
此类的行为与原始类 (SimpleAdapter) 完全相同