我正在开发一个用于连接php和mssql与android的项目。每当我尝试调用一个类时，应用程序就会停止工作。看看下面的代码，并建议我做错了什么。 MainActivity.java
public class MainActivity extends Activity {
TabHost host;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Resources res = getResources();
host = (TabHost) findViewById (R.id.tabhost);
host.setup();
TabSpec tspecMovies = host.newTabSpec("tag1");
// tspecMovies.setContent(R.id.tab1);
tspecMovies.setIndicator("Movies", res.getDrawable(R.drawable.movie_icon));
Intent intentMovie = new Intent(this, MovieActivity.class);
tspecMovies.setContent(intentMovie);
host.addTab(tspecMovies);
TabSpec tspecTv = host.newTabSpec("tag2");
tspecTv.setContent(R.id.tab2);
tspecTv.setIndicator("TV", res.getDrawable(R.drawable.tv_icon));
host.addTab(tspecTv);
TabSpec tspecEvents = host.newTabSpec("tag3");
tspecEvents.setContent(R.id.tab3);
tspecEvents.setIndicator("Events", res.getDrawable(R.drawable.event_icon));
host.addTab(tspecEvents);
for(int i=0;i<host.getTabWidget().getChildCount();i++){
host.getTabWidget().getChildAt(i).setBackgroundColor(Color.parseColor("#373737")); //unselected
}
host.getTabWidget().getChildAt(host.getCurrentTab()).setBackgroundColor(Color.parseColor("#717171"));// selected
host.setOnTabChangedListener(new OnTabChangeListener(){
@Override
public void onTabChanged(String tabId) {
for(int i=0;i<host.getTabWidget().getChildCount();i++){
host.getTabWidget().getChildAt(i).setBackgroundColor(Color.parseColor("#373737")); // unselected
}
host.getTabWidget().getChildAt(host.getCurrentTab()).setBackgroundColor(Color.parseColor("#717171"));// selected
}});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
我目前正在使用电影标签。我想在通过调用以下MovieActivity点击Movies标签时列出我的tbl_cimemas表中的所有cinema_name。
public class MovieActivity extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
private static String url_all_cinemas = "http://localhost:8080/android/get_all_cinema.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_CINEMAS = "tbl_cinemas";
private static final String TAG_CID = "cinema_id";
private static final String TAG_NAME = "cinema_name";
// products JSONArray
JSONArray products = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_cinema);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading products in Background Thread
new LoadAllProducts().execute();
}
/**
* Background Async Task to Load all product by making HTTP Request
* */
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MovieActivity.this);
pDialog.setMessage("Loading products. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_cinemas, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Products: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
products = json.getJSONArray(TAG_CINEMAS);
// looping through All Products
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_CID);
String name = c.getString(TAG_NAME);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_CID, id);
map.put(TAG_NAME, name);
// adding HashList to ArrayList
productsList.add(map);
}
} else {
// no products found
// Launch Add New product Activity
Intent i = new Intent(getApplicationContext(),
MovieActivity.class);
// Closing all previous activities
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
MovieActivity.this, productsList,
R.layout.list_cinema, new String[] { TAG_CID,
TAG_NAME},
new int[] { R.id.cid, R.id.name });
// updating listview
setListAdapter(adapter);
}
});
}
}
all_cinema.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<!-- Main ListView
Always give id value as list(@android:id/list)
-->
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
list_cinema.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<!-- Cinema id (cid) - will be HIDDEN - used to pass to other activity -->
<TextView
android:id="@+id/cid"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<!-- Name Label -->
<TextView
android:id="@+id/name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingTop="6sp"
android:paddingLeft="6sp"
android:textSize="17sp"
android:textStyle="bold"
android:clickable="true"
android:textIsSelectable="true" />
</LinearLayout>
logcat的
09-08 07:21:30.632: D/dalvikvm(778): GC_CONCURRENT freed 70K, 8% free 2735K/2948K, paused 10ms+71ms, total 250ms
09-08 07:21:31.053: D/AndroidRuntime(778): Shutting down VM
09-08 07:21:31.083: W/dalvikvm(778): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
09-08 07:21:31.133: E/AndroidRuntime(778): FATAL EXCEPTION: main
09-08 07:21:31.133: E/AndroidRuntime(778): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.myandroidapp/com.example.myandroidapp.MainActivity}: java.lang.IllegalStateException: Did you forget to call 'public void setup(LocalActivityManager activityGroup)'?
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread.access$600(ActivityThread.java:141)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.os.Handler.dispatchMessage(Handler.java:99)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.os.Looper.loop(Looper.java:137)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread.main(ActivityThread.java:5041)
09-08 07:21:31.133: E/AndroidRuntime(778): at java.lang.reflect.Method.invokeNative(Native Method)
09-08 07:21:31.133: E/AndroidRuntime(778): at java.lang.reflect.Method.invoke(Method.java:511)
09-08 07:21:31.133: E/AndroidRuntime(778): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
09-08 07:21:31.133: E/AndroidRuntime(778): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
09-08 07:21:31.133: E/AndroidRuntime(778): at dalvik.system.NativeStart.main(Native Method)
09-08 07:21:31.133: E/AndroidRuntime(778): Caused by: java.lang.IllegalStateException: Did you forget to call 'public void setup(LocalActivityManager activityGroup)'?
09-08 07:21:31.133: E/AndroidRuntime(778): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:747)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.widget.TabHost.setCurrentTab(TabHost.java:413)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.widget.TabHost.addTab(TabHost.java:240)
09-08 07:21:31.133: E/AndroidRuntime(778): at com.example.myandroidapp.MainActivity.onCreate(MainActivity.java:31)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.Activity.performCreate(Activity.java:5104)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
09-08 07:21:31.133: E/AndroidRuntime(778): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
09-08 07:21:31.133: E/AndroidRuntime(778): ... 11 more
09-08 07:22:17.282: I/Process(778): Sending signal. PID: 778 SIG: 9
答案 0 :(得分：0)
它的外观类似StackOverflow : llegalstateexception-at-tabhost， 您正在尝试扩展活动，尝试扩展TabActivity类
检查接受的答案。