android开发问题~~~在线等

qq_26441279 2016-07-24 12:51:09


public class MainActivity extends Activity {
private final int COLUMNWIDTHPX = 500;
private final int FLINGVELOCITYPX = 9500;
private final int NEWSCOUNT = 5; //返回新闻数目
private final int SUCCESS = 0;//加载成功
private final int NONEWS = 1;//该栏目下没有新闻
private final int NOMORENEWS = 2;//该栏目下没有更多新闻
private final int LOADERROR = 3;//加载失败

private int mColumnWidthDip;
private int mFlingVelocityDip;
private ArrayList<HashMap<String, Object>> mNewsData;
private ListView mNewsList;
private int mCid;
private String mCatName;
private SimpleAdapter mNewsListAdapter;
private LayoutInflater mInflater;
private Button mTitlebarRefresh;
private ProgressBar mLoadnewsProgress;
private Button mLoadMoreBtn;

private LoadNewsAsyncTask loadNewsAsyncTask;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

mInflater = getLayoutInflater();

mNewsData = new ArrayList<HashMap<String,Object>>();
mNewsList = (ListView)findViewById(R.id.newslist);

mTitlebarRefresh = (Button)findViewById(R.id.titlebar_refresh);
mLoadnewsProgress = (ProgressBar)findViewById(R.id.loadnews_progress);
mTitlebarRefresh.setOnClickListener(loadMoreListener);

//把px转换成dip
mColumnWidthDip = DensityUtil.px2dip(this, COLUMNWIDTHPX);
mFlingVelocityDip = DensityUtil.px2dip(this, FLINGVELOCITYPX);


//获取新闻分类
String[] categoryArray = getResources().getStringArray(R.array.categories);
//把新闻分类保存到List中
final List<HashMap<String, Category>> categories = new ArrayList<HashMap<String, Category>>();
//分割新闻类型字符串
for(int i=0;i<categoryArray.length;i++)
{
String[] temp = categoryArray[i].split("[|]");
if (temp.length==2)
{
int cid = StringUtil.String2Int(temp[0]);
String title = temp[1];
Category type = new Category(cid, title);
HashMap<String, Category> hashMap = new HashMap<String, Category>();
hashMap.put("category_title", type);
categories.add(hashMap);
}
}

//默认选中的新闻分类
mCid = 1;
mCatName ="关于我们";
//创建Adapter，指明映射字段
//SimpleAdapter categoryAdapter = new SimpleAdapter(this, categories, R.layout.category_title,new String[]{"category_title"}, new int[]{R.id.category_title});
CustomSimpleAdapter categoryAdapter = new CustomSimpleAdapter(this, categories, R.layout.category_title,new String[]{"category_title"}, new int[]{R.id.category_title});


GridView category = new GridView(this);
category.setColumnWidth(mColumnWidthDip);//每个单元格宽度
category.setNumColumns(GridView.AUTO_FIT);//单元格数目
category.setGravity(Gravity.CENTER);//设置对其方式
//设置单元格选择是背景色为透明，这样选择时就不现实黄色背景
//category.setSelector(new ColorDrawable(Color.TRANSPARENT));

int width = mColumnWidthDip * categories.size();
LayoutParams params = new LayoutParams(width, LayoutParams.FILL_PARENT);
//更新category宽度和高度，这样category在一行显示
category.setLayoutParams(params);

//设置适配器
category.setAdapter(categoryAdapter);
//把category加入到容器中
LinearLayout categoryList = (LinearLayout) findViewById(R.id.category_layout);
categoryList.addView(category);

//添加单元格点击事件
category.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id){
TextView categoryTitle;
//恢复每个单元格背景色
for (int i = 0; i < parent.getChildCount(); i++){
categoryTitle = (TextView) (parent.getChildAt(i));
categoryTitle.setBackgroundDrawable(null);
categoryTitle.setTextColor(0XFFADB2AD);
}
//设置选择单元格的背景色
categoryTitle = (TextView) (parent.getChildAt(position));
categoryTitle.setBackgroundResource(R.drawable.categorybar_item_background);
categoryTitle.setTextColor(0XFFFFFFFF);
//获取选中的新闻分类id
mCid = categories.get(position).get("category_title").getCid();
mCatName = categories.get(position).get("category_title").getTitle();
//获取该栏目下新闻
//getSpeCateNews(mCid,mNewsData,0,true);
//通知ListView进行更新
//mNewsListAdapter.notifyDataSetChanged();
loadNewsAsyncTask = new LoadNewsAsyncTask();
loadNewsAsyncTask.execute(mCid,0,true);
}
});

// 箭头
final HorizontalScrollView categoryScrollView = (HorizontalScrollView)findViewById(R.id.category_scrollview);
Button categoryArrowRight = (Button)findViewById(R.id.category_arrow_right);
categoryArrowRight.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View v){
categoryScrollView.fling(mFlingVelocityDip);
}
});
//填充ListView，在里边显示新闻列表
/*List<HashMap<String, String>> newsData = new ArrayList<HashMap<String, String>>();
for(int i = 0; i < 10; i++){
HashMap<String, String> hashMap = new HashMap<String, String>();
hashMap.put("newslist_item_title", "中天");
hashMap.put("newslist_item_digest", "中天信息公司成立了");
hashMap.put("newslist_item_source", "来自中天");
hashMap.put("newslist_item_ptime", "2013-03-07");
newsData.add(hashMap);
}*/
//获取指定栏目的新闻列表
getSpeCateNews(mCid,mNewsData,0,true);
mNewsListAdapter = new SimpleAdapter(this, mNewsData, R.layout.newslist_item,
new String[]{"newslist_item_title", "newslist_item_digest", "newslist_item_source", "newslist_item_ptime"},
new int[]{R.id.newslist_item_title, R.id.newslist_item_digest, R.id.newslist_item_source, R.id.newslist_item_ptime});
View loadMoreLayout = mInflater.inflate(R.layout.loadmore, null);
mNewsList.addFooterView(loadMoreLayout);
mNewsList.setAdapter(mNewsListAdapter);
mNewsList.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id){
Intent intent = new Intent(MainActivity.this, NewsDetailsActivity.class);
//把需要的信息放到Intent中;
intent.putExtra("categoryName", mCatName);
intent.putExtra("newsDate", mNewsData);
intent.putExtra("position", position);
startActivity(intent);
}
});

mLoadMoreBtn = (Button)findViewById(R.id.loadmore_btn);
mLoadMoreBtn.setOnClickListener(loadMoreListener);

loadNewsAsyncTask = new LoadNewsAsyncTask();
loadNewsAsyncTask.execute(mCid,0,true);
}

/**
* 获取指定类型的新闻列表
* @param cid 类型ID
* @param newsList 保存新闻信息的集合
* @param startnid 分页
* @param firstTimes 是否第一次加载
*/
private int getSpeCateNews(int cid,List<HashMap<String, Object>> newsList,int startnid,Boolean firstTimes){
if (firstTimes){
//如果是第一次，则清空集合里数据
newsList.clear();
}
//请求URL和字符串
String url = "http://192.168.0.101:8080/web/getSpecifyCategoryNews";
String params = "startnid="+startnid+"&count="+NEWSCOUNT+"&cid="+cid;
SyncHttp syncHttp = new SyncHttp();
try{
//以Get方式请求，并获得返回结果
String retStr = syncHttp.httpGet(url, params);
JSONObject jsonObject = new JSONObject(retStr);
//获取返回码，0表示成功
int retCode = jsonObject.getInt("ret");
if (0==retCode){
JSONObject dataObject = jsonObject.getJSONObject("data");
//获取返回数目
int totalnum = dataObject.getInt("totalnum");
if (totalnum>0){
//获取返回新闻集合
JSONArray newslist = dataObject.getJSONArray("newslist");
for(int i=0;i<newslist.length();i++){
JSONObject newsObject = (JSONObject)newslist.opt(i);
HashMap<String, Object> hashMap = new HashMap<String, Object>();
hashMap.put("nid", newsObject.getInt("nid"));
hashMap.put("newslist_item_title", newsObject.getString("title"));
hashMap.put("newslist_item_digest", newsObject.getString("digest"));
hashMap.put("newslist_item_source", newsObject.getString("source"));
hashMap.put("newslist_item_ptime", newsObject.getString("ptime"));
hashMap.put("newslist_item_comments", newsObject.getString("commentcount"));
newsList.add(hashMap);
}
return SUCCESS;
}
else{
if (firstTimes){
return NONEWS;
}
else{
return NOMORENEWS;
}
}
}
else{
return LOADERROR;
}
} catch (Exception e){
e.printStackTrace();
return LOADERROR;
}
}

private OnClickListener loadMoreListener = new OnClickListener(){
@Override
public void onClick(View v){
loadNewsAsyncTask = new LoadNewsAsyncTask();
switch (v.getId()){
case R.id.loadmore_btn:
//获取该栏目下新闻
//getSpeCateNews(mCid,mNewsData,mNewsData.size(),false);
//通知ListView进行更新
//mNewsListAdapter.notifyDataSetChanged();
loadNewsAsyncTask.execute(mCid,mNewsData.size(),false);
break;
case R.id.titlebar_refresh:
loadNewsAsyncTask.execute(mCid,0,true);
break;
}

}
};

private class LoadNewsAsyncTask extends AsyncTask<Object, Integer, Integer>{

@Override
protected void onPreExecute(){
//隐藏刷新按钮
mTitlebarRefresh.setVisibility(View.GONE);
//显示进度条
mLoadnewsProgress.setVisibility(View.VISIBLE);
//设置LoadMore Button 显示文本
mLoadMoreBtn.setText(R.string.loadmore_txt);
}

@Override
protected Integer doInBackground(Object... params){


int a=getSpeCateNews((Integer)params[0],mNewsData,(Integer)params[1],(Boolean)params[2]);
mNewsListAdapter.notifyDataSetChanged();
return a;
}

@Override
protected void onPostExecute(Integer result){
//根据返回值显示相关的Toast
switch (result){
case NONEWS:
Toast.makeText(MainActivity.this, R.string.no_news, Toast.LENGTH_LONG).show();
break;
case NOMORENEWS:
Toast.makeText(MainActivity.this, R.string.no_more_news, Toast.LENGTH_LONG).show();
break;
case LOADERROR:
Toast.makeText(MainActivity.this, R.string.load_news_failure, Toast.LENGTH_LONG).show();
break;
}
//显示刷新按钮
mTitlebarRefresh.setVisibility(View.VISIBLE);
//隐藏进度条
mLoadnewsProgress.setVisibility(View.GONE);
//设置LoadMore Button 显示文本
mLoadMoreBtn.setText(R.string.loadmore_btn);
//mNewsListAdapter.notifyDataSetChanged();
}
}
}
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adfldk 2016-07-25
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帮你改错？　是不是不会看error提示,不知啥意思可以先百度
qq_26441279 2016-07-24
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错误信息 07-24 12:54:09.491: E/AndroidRuntime(5301): FATAL EXCEPTION: AsyncTask #4 07-24 12:54:09.491: E/AndroidRuntime(5301): Process: com.ztt.news.activity, PID: 5301 07-24 12:54:09.491: E/AndroidRuntime(5301): java.lang.RuntimeException: An error occured while executing doInBackground() 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.os.AsyncTask$3.done(AsyncTask.java:304) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.FutureTask.run(FutureTask.java:242) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.lang.Thread.run(Thread.java:818) 07-24 12:54:09.491: E/AndroidRuntime(5301): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views. 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:7179) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:1065) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.View.requestLayout(View.java:17941) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.View.requestLayout(View.java:17941) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.View.requestLayout(View.java:17941) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.View.requestLayout(View.java:17941) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.view.View.requestLayout(View.java:17941) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.widget.AbsListView.requestLayout(AbsListView.java:2135) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.widget.AdapterView$AdapterDataSetObserver.onChanged(AdapterView.java:828) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.widget.AbsListView$AdapterDataSetObserver.onChanged(AbsListView.java:6852) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:37) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50) 07-24 12:54:09.491: E/AndroidRuntime(5301): at com.ztt.news.activity.MainActivity$LoadNewsAsyncTask.doInBackground(MainActivity.java:296) 07-24 12:54:09.491: E/AndroidRuntime(5301): at com.ztt.news.activity.MainActivity$LoadNewsAsyncTask.doInBackground(MainActivity.java:1) 07-24 12:54:09.491: E/AndroidRuntime(5301): at android.os.AsyncTask$2.call(AsyncTask.java:292) 07-24 12:54:09.491: E/AndroidRuntime(5301): at java.util.concurrent.FutureTask.run(FutureTask.java:237) 07-24 12:54:09.491: E/AndroidRuntime(5301): ... 4 more
magicyang1234 2016-07-24
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07-24 12:54:09.491: E/AndroidRuntime(5301): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views. protected Integer doInBackground(Object... params){ int a=getSpeCateNews((Integer)params[0],mNewsData,(Integer)params[1],(Boolean)params[2]); mNewsListAdapter.notifyDataSetChanged(); //非主线程，不要刷新ADAPTER.放到onPostExecute里面去。 return a; }
Hbale 2016-07-24
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学会看报错先，主要的就这个 java.lang.RuntimeException: An error occured while executing doInBackground()
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