Android 加载更多-只有创建视图层次结构的原始线程才能接触其视图
我的应用程序正在使用GridView从JSON获取图像。一切都很好,但现在我想让它加载更多的点击按钮。我遵循了这个教程。 当我遵循它时,我使用了Android 加载更多-只有创建视图层次结构的原始线程才能接触其视图,android,json,gridview,android-asynctask,android-loader,Android,Json,Gridview,Android Asynctask,Android Loader,我的应用程序正在使用GridView从JSON获取图像。一切都很好,但现在我想让它加载更多的点击按钮。我遵循了这个教程。 当我遵循它时,我使用了runOnUiThread(newrunnable()){ public void run(){}在doInBackground中,但它会出错networkonmainthreadeception我知道这一点,因为我在UI线程上运行它。但是当我删除runOnUiThread…时,它也会出错 如何修复此错误?完整源代码 首次加载时执行异步任务 // Dow
runOnUiThread(newrunnable()){
public void run(){}
在doInBackground
中,但它会出错networkonmainthreadeception
我知道这一点,因为我在UI线程上运行它。但是当我删除runOnUiThread…
时,它也会出错
如何修复此错误?完整源代码
首次加载时执行异步任务
// Download JSON in Background
public class DownloadJSONFileAsync extends AsyncTask<String, Void, Void> {
String token = getIntent().getExtras().getString("token1");
protected void onPreExecute() {
super.onPreExecute();
showDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
}
@Override
protected Void doInBackground(String... params) {
String url = "http://xxx.xxx.xxx/card/all/"+num_page+"/0/?token="+token;
JSONArray data = null;
try {
JSONObject jsonObject = new JSONObject(getJSONUrl(url));
MyArrList = new ArrayList<HashMap<String, Object>>();
HashMap<String, Object> map;
data = jsonObject.getJSONArray("data");
for (int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, Object>();
// Thumbnail Get ImageBitmap To Object
map.put("cardimage", (String) c.getString("cardimage"));
map.put("ImageThumBitmap",(Bitmap) loadBitmap(c.getString("cardimage")));
map.put("categoryid", (String) c.getString("categoryid"));
MyArrList.add(map);
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
protected void onPostExecute(Void unused) {
ShowAllContent(); // When Finish Show Content
dismissDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
removeDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
}
}
//在后台下载JSON
公共类下载JSonfileasync扩展异步任务{
字符串标记=getIntent().getExtras().getString(“标记1”);
受保护的void onPreExecute(){
super.onPreExecute();
showDialog(DIALOG\u下载\u JSON\u进度);
}
@凌驾
受保护的Void doInBackground(字符串…参数){
字符串url=”http://xxx.xxx.xxx/card/all/“+num_page+”/0/?token=“+token;
JSONArray数据=null;
试一试{
JSONObject JSONObject=新的JSONObject(getJSONUrl(url));
MyArrList=newarraylist();
HashMap图;
data=jsonObject.getJSONArray(“数据”);
对于(int i=0;i
使用按钮单击以加载更多内容时的AsycTask
// load more
public class LoadMore extends AsyncTask<String, Void, Void> {
String token = getIntent().getExtras().getString("token1");
protected void onPreExecute() {
super.onPreExecute();
showDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
}
@Override
protected Void doInBackground(String... params) {
num_page += 1;
String url = "http://xxx.xxx.xxx/card/all/"+num_page+"/0/?token="+token;
JSONArray data = null;
try {
JSONObject jsonObject = new JSONObject(getJSONUrl(url));
MyArrList = new ArrayList<HashMap<String, Object>>();
HashMap<String, Object> map;
data = jsonObject.getJSONArray("data");
for (int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, Object>();
// Thumbnail Get ImageBitmap To Object
map.put("cardimage", (String) c.getString("cardimage"));
map.put("ImageThumBitmap",(Bitmap) loadBitmap(c.getString("cardimage")));
map.put("categoryid", (String) c.getString("categoryid"));
MyArrList.add(map);
}
int currentPosition = gridView1.getFirstVisiblePosition();
ImageAdapter adapter = new ImageAdapter(CardActivity.this, MyArrList);
gridView1.setAdapter(adapter);
gridView1.setSelection(currentPosition + 1);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
protected void onPostExecute(Void unused) {
ShowAllContent();
dismissDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
removeDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
}
}
//加载更多
公共类LoadMore扩展异步任务{
字符串标记=getIntent().getExtras().getString(“标记1”);
受保护的void onPreExecute(){
super.onPreExecute();
showDialog(DIALOG\u下载\u JSON\u进度);
}
@凌驾
受保护的Void doInBackground(字符串…参数){
页数+=1;
字符串url=”http://xxx.xxx.xxx/card/all/“+num_page+”/0/?token=“+token;
JSONArray数据=null;
试一试{
JSONObject JSONObject=新的JSONObject(getJSONUrl(url));
MyArrList=newarraylist();
HashMap图;
data=jsonObject.getJSONArray(“数据”);
对于(int i=0;i
您可能应该移动此代码:
int currentPosition = gridView1.getFirstVisiblePosition();
ImageAdapter adapter = new ImageAdapter(CardActivity.this, MyArrList);
gridView1.setAdapter(adapter);
gridView1.setSelection(currentPosition + 1);
进入
onPostExecute
方法,因为它必须在UI线程上运行gridView1.setSelection(currentPosition+1);?
中的1
是什么意思?因为我将其更改为0,它工作得很好非常感谢,你的ans。节省了我的很多时间……谢谢,我需要在pnPostExecute()上添加我的setadaper而不是在后台
int currentPosition = gridView1.getFirstVisiblePosition();
ImageAdapter adapter = new ImageAdapter(CardActivity.this, MyArrList);
gridView1.setAdapter(adapter);
gridView1.setSelection(currentPosition + 1);