我有一个带有2个图像按钮的活动。活动扩展为DialogFragment。每当我尝试创建一个Intent时：
Intent in = new Intent(this, ChatActivity.class)
建议删除参数时出错。如何在ImageButtons上创建这些Intent？
VotingActivity.java
public class VotingDialog extends DialogFragment{
private ImageButton isupport;
private ImageButton iagainst;
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState){
final View view = inflater.inflate(R.layout.activity_voting_dialog, container);
getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);
final ImageButton isupport = (ImageButton) view.findViewById(R.id.isupport);
final ImageButton iagainst = (ImageButton) view.findViewById(R.id.iagainst);
isupport.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View view) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity(), ChatActivity.java);
startActivity(intent);
}
});
return view;
}
}
logcat的：
05-30 00:33:20.865: W/IInputConnectionWrapper(10881): getSelectedText on inactive InputConnection
05-30 00:33:20.935: W/IInputConnectionWrapper(10881): setComposingText on inactive InputConnection
05-30 00:33:22.355: D/dalvikvm(10881): GC_CONCURRENT freed 2357K, 25% free 9992K/13315K, paused 14ms+20ms, total 126ms
05-30 00:33:22.455: E/SpannableStringBuilder(10881): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
05-30 00:33:22.455: E/SpannableStringBuilder(10881): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
05-30 00:33:23.205: E/SpannableStringBuilder(10881): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
05-30 00:33:23.205: E/SpannableStringBuilder(10881): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
05-30 00:33:24.645: D/AndroidRuntime(10881): Shutting down VM
05-30 00:33:24.645: W/dalvikvm(10881): threadid=1: thread exiting with uncaught exception (group=0x40fd4438)
05-30 00:33:24.665: E/AndroidRuntime(10881): FATAL EXCEPTION: main
05-30 00:33:24.665: E/AndroidRuntime(10881): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.social.knowtide/com.social.knowtide.ChatActivity}: java.lang.NullPointerException
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2114)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2139)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread.access$700(ActivityThread.java:143)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1241)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.os.Handler.dispatchMessage(Handler.java:99)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.os.Looper.loop(Looper.java:137)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread.main(ActivityThread.java:4963)
05-30 00:33:24.665: E/AndroidRuntime(10881): at java.lang.reflect.Method.invokeNative(Native Method)
05-30 00:33:24.665: E/AndroidRuntime(10881): at java.lang.reflect.Method.invoke(Method.java:511)
05-30 00:33:24.665: E/AndroidRuntime(10881): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
05-30 00:33:24.665: E/AndroidRuntime(10881): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
05-30 00:33:24.665: E/AndroidRuntime(10881): at dalvik.system.NativeStart.main(Native Method)
05-30 00:33:24.665: E/AndroidRuntime(10881): Caused by: java.lang.NullPointerException
05-30 00:33:24.665: E/AndroidRuntime(10881): at com.social.knowtide.ChatActivity.onCreate(ChatActivity.java:40)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.Activity.performCreate(Activity.java:5184)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
05-30 00:33:24.665: E/AndroidRuntime(10881): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2078)
05-30 00:33:24.665: E/AndroidRuntime(10881): ... 11 more
ChatActivity.java
public class ChatActivity extends Activity implements ChatCallbackAdapter {
SocketIO socket;
ChatCallbackAdapter callback;
Chat chat;
TextView tv;
EditText ed;
String nickname;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_chat);
Bundle in = getIntent().getExtras();
//final String disctext = in.getString("distext");
final String disid = in.getString("disid");
//final String detailsdesc = in.getString("detaildesc");
Button button = (Button) findViewById(R.id.button1);
tv = (TextView) findViewById(R.id.reply);
ed = (EditText)findViewById(R.id.editText1);
//TextView discussiontext = (TextView)findViewById(R.id.discussiontext1);
//RelativeLayout rel = (RelativeLayout)findViewById(R.id.rellayout);
//discussiontext.setText(disctext);
/*rel.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(ChatActivity.this,DiscussionDetailActivity.class);
Bundle b = new Bundle();
b.putString("disid", disid);
b.putString("distext", disctext);
b.putString("detaildesc",detailsdesc );
i.putExtras(b);
startActivity(i);
}
});*/
this.runOnUiThread(new Runnable() {
@Override
public void run() {
startChat();
}
private void startChat() {
// TODO Auto-generated method stub
tv.append("Connecting...");
chat = new Chat(ChatActivity.this);
chat.start();
} });
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
nickname = new LoginSharePreferences().getName(ChatActivity.this);
System.out.println(disid);
chat.sendMessage(ed.getText().toString(),disid,nickname);
ed.setText("");
}
});
}
@Override
public void callback(JSONArray data) throws JSONException {}
@Override
public void on(String event, final JSONObject obj1) {
if (event.equals("user message")) {
this.runOnUiThread(new Runnable() {
JSONObject obj = obj1;
@Override
public void run() {
// TODO Auto-generated method stub
try {
tv.append(obj.getString("user") + ": " + obj.getString("message")+ "\n");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
else if (event.equals("announcement")) {
this.runOnUiThread(new Runnable() {
JSONObject obj = obj1;
@Override
public void run() {
try {
tv.append(obj.getString("user") + " " + obj.getString("action") + "\n");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
/*else if (event.equals("nicknames")) {
JSONArray names = obj1.names();
String str = "";
for (int i=0; i < names.length(); i++) {
if (i != 0)
str += ", ";
str += names.getString(i);
}
OnlineUsers.setText(str);
}*/
}
@Override
public void onMessage(String message) {}
@Override
public void onMessage(JSONObject json) {}
@Override
public void onConnect() {
this.runOnUiThread(new Runnable() {
@Override
public void run() {
tv.append("done!\n");
} });
// String nickname = new LoginSharePreferences().getName(this);
//System.out.println(nickname + "kuch nhi aya");
if (!nickname.equals(null)) {
chat.join(nickname);
// tv.append( nickname +"join the debate" + "\n");
}
}
@Override
public void onDisconnect() {
Toast.makeText(ChatActivity.this,"Connection lost",Toast.LENGTH_LONG).show();
}
@Override
public void onConnectFailure() {
this.runOnUiThread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
tv.append("error!\n");
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.chat, menu);
return true;
}
}
答案 0 :(得分：0)
不在活动环境中，因此请使用Intent in = new Intent(getActivity() , ChatActivity.class) ;