Android ListView的内容占用大量内存
Android ListView的内容占用大量内存,android,memory-leaks,bitmap,android-listview,android-viewbinder,Android,Memory Leaks,Bitmap,Android Listview,Android Viewbinder,ListView包含相当多的项目(20个或更多),每个项目都是一个带有位图源的ImageView。这些位图未压缩,大小约为640x480。当刚刚加载列表视图时,它需要一些内存,但是如果我滚动它,则可能会出现错误“内存超过VM budjet”。当我用另一个片段替换该片段时,ListView仍挂在内存中。如何清除ram/ListView缓存 更新: 我将SimpleCursorAdapter与ViewBinder一起使用: SimpleCursorAdapter.ViewBinder vie
ListView
包含相当多的项目(20个或更多),每个项目都是一个带有位图源的ImageView
。这些位图未压缩,大小约为640x480。当刚刚加载列表视图时,它需要一些内存,但是如果我滚动它,则可能会出现错误“内存超过VM budjet”
。当我用另一个片段替换该片段时,ListView
仍挂在内存中。如何清除ram/ListView缓存
更新:
我将SimpleCursorAdapter
与ViewBinder
一起使用:
SimpleCursorAdapter.ViewBinder viewBinder = new SimpleCursorAdapter.ViewBinder() {
public boolean setViewValue(View view, Cursor cursor, int columnIndex) {
if (columnIndex == 0) {
TextView tv1 = (TextView) view;
if (cursor.getInt(4) == 0)
tv1.setTextColor(Color.GRAY);
else
tv1.setTextColor(Color.parseColor("#191919"));
tv1.setText(cursor.getString(columnIndex));
}
if (columnIndex == 3) {
TextView tv1 = (TextView) view;
tv1.setText(cursor.getString(columnIndex));
}
if (columnIndex == 2) {
final ImageView image = (ImageView) view;
Bitmap cachedImage = null;
try {
cachedImage = imageThreadLoader.loadImage(cursor.getString(columnIndex), new ImageThreadLoader.ImageLoadedListener() {
public void imageLoaded(Bitmap imageBitmap) {
image.setImageBitmap((Bitmap) new SoftReference(imageBitmap).get());
}
});
} catch (MalformedURLException mue) {
Log.e("Feeds fragment", "Can't load image");
}
if (cachedImage != null) {
image.setImageBitmap(cachedImage);
} else image.setImageDrawable(getResources().getDrawable(R.drawable.icon));
}
图像加载到单独的线程中。像这样构建listview创建自定义适配器并将其设置为listview
public class InteractiveArrayAdapter extends ArrayAdapter<Model> {
private final List<Model> list;
private final Activity context;
public InteractiveArrayAdapter(Activity context, List<Model> list) {
super(context, R.layout.main, list);
this.context = context;
this.list = list;
}
static class ViewHolder {
protected TextView text;
protected CheckBox checkbox;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
if (convertView == null) {
LayoutInflater inflator = context.getLayoutInflater();
view = inflator.inflate(R.layout.main, null);
final ViewHolder viewHolder = new ViewHolder();
viewHolder.text = (TextView) view.findViewById(R.id.listitem_text);
viewHolder.checkbox = (CheckBox) view.findViewById(R.id.checkBox1);
viewHolder.checkbox
.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
Model element = (Model) viewHolder.checkbox
.getTag();
element.setSelected(buttonView.isChecked());
}
});
view.setTag(viewHolder);
viewHolder.checkbox.setTag(list.get(position));
} else {
view = convertView;
((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
}
ViewHolder holder = (ViewHolder) view.getTag();
holder.text.setText(list.get(position).getName());
holder.checkbox.setChecked(list.get(position).isSelected());
return view;
}
}
公共类InteractiveArrayAdapter扩展了ArrayAdapter{
私人最终名单;
私人最终活动背景;
公共InteractiveArrayAdapter(活动上下文、列表){
super(上下文、右布局、主视图、列表);
this.context=上下文;
this.list=列表;
}
静态类视窗夹{
受保护的文本查看文本;
受保护复选框;
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组父视图){
视图=空;
if(convertView==null){
LayoutInflater充气器=上下文。getLayoutInflater();
视图=充气机充气(R.layout.main,空);
最终ViewHolder ViewHolder=新的ViewHolder();
viewHolder.text=(TextView)view.findViewById(R.id.listitem_text);
viewHolder.checkbox=(checkbox)view.findViewById(R.id.checkBox1);
viewHolder.checkbox
.setOnCheckedChangeListener(新建CompoundButton.OnCheckedChangeListener(){
检查更改后的公共无效(复合按钮视图,
布尔值(已检查){
模型元素=(模型)viewHolder.checkbox
.getTag();
element.setSelected(buttonView.isChecked());
}
});
view.setTag(viewHolder);
viewHolder.checkbox.setTag(list.get(position));
}否则{
视图=转换视图;
((ViewHolder)view.getTag()).checkbox.setTag(list.get(position));
}
ViewHolder=(ViewHolder)view.getTag();
holder.text.setText(list.get(position.getName());
holder.checkbox.setChecked(list.get(position.isSelected());
返回视图;
}
}
尝试这种方式,您不必要的视图将被回收,执行速度将更快,希望您能消除错误,像这样构建listview创建自定义适配器并将其设置为listview
public class InteractiveArrayAdapter extends ArrayAdapter<Model> {
private final List<Model> list;
private final Activity context;
public InteractiveArrayAdapter(Activity context, List<Model> list) {
super(context, R.layout.main, list);
this.context = context;
this.list = list;
}
static class ViewHolder {
protected TextView text;
protected CheckBox checkbox;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
if (convertView == null) {
LayoutInflater inflator = context.getLayoutInflater();
view = inflator.inflate(R.layout.main, null);
final ViewHolder viewHolder = new ViewHolder();
viewHolder.text = (TextView) view.findViewById(R.id.listitem_text);
viewHolder.checkbox = (CheckBox) view.findViewById(R.id.checkBox1);
viewHolder.checkbox
.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
Model element = (Model) viewHolder.checkbox
.getTag();
element.setSelected(buttonView.isChecked());
}
});
view.setTag(viewHolder);
viewHolder.checkbox.setTag(list.get(position));
} else {
view = convertView;
((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
}
ViewHolder holder = (ViewHolder) view.getTag();
holder.text.setText(list.get(position).getName());
holder.checkbox.setChecked(list.get(position).isSelected());
return view;
}
}
公共类InteractiveArrayAdapter扩展了ArrayAdapter{
私人最终名单;
私人最终活动背景;
公共InteractiveArrayAdapter(活动上下文、列表){
super(上下文、右布局、主视图、列表);
this.context=上下文;
this.list=列表;
}
静态类视窗夹{
受保护的文本查看文本;
受保护复选框;
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组父视图){
视图=空;
if(convertView==null){
LayoutInflater充气器=上下文。getLayoutInflater();
视图=充气机充气(R.layout.main,空);
最终ViewHolder ViewHolder=新的ViewHolder();
viewHolder.text=(TextView)view.findViewById(R.id.listitem_text);
viewHolder.checkbox=(checkbox)view.findViewById(R.id.checkBox1);
viewHolder.checkbox
.setOnCheckedChangeListener(新建CompoundButton.OnCheckedChangeListener(){
检查更改后的公共无效(复合按钮视图,
布尔值(已检查){
模型元素=(模型)viewHolder.checkbox
.getTag();
element.setSelected(buttonView.isChecked());
}
});
view.setTag(viewHolder);
viewHolder.checkbox.setTag(list.get(position));
}否则{
视图=转换视图;
((ViewHolder)view.getTag()).checkbox.setTag(list.get(position));
}
ViewHolder=(ViewHolder)view.getTag();
holder.text.setText(list.get(position.getName());
holder.checkbox.setChecked(list.get(position.isSelected());
返回视图;
}
}
尝试这种方式,您不必要的视图将被回收,执行速度将更快,希望您能消除错误我建议您观看关于ListView的Google IO。它包含内存节省技术,帮助我理解ListView的逻辑。我建议您观看关于ListView的Google IO。它包含内存节省技术,帮助我理解listview的逻辑。可能是您的listview不回收视图。我的意思是listview默认情况下回收视图以提高内存利用率,如果你可以发布你的getview方法,让事情变得更清晰,可能是你的listview不回收视图我的意思是listview默认情况下回收视图以提高内存利用率,如果你可以发布你的getview方法,让事情变得更清晰如果我使用你的,我必须将位图列表放入适配器的构造函数中,在片段的整个生命周期中,它都将存储在ram中,但当我看到必要的列表项时,我想从外部存储器中加载图像,当它消失时卸载位图(当我滚动列表时)。对不起,我还没有做过类似的事情。但我会尝试一下。如果我找到任何方法,请告诉你。如果我使用你的,我必须把位图