我把头撞在墙上，试图解决这个问题一段时间。我不是一个有经验的 Android 人，所以它的解决方案可能非常简单。话虽如此，我有以下代码：
@Override
protected void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.adminusers);
super.onCreate(savedInstanceState);
// set user_type for Viewall
mUserType = 0;
lv_adminusersListContent.addFooterView(footerView);
mUsersAdapter = new AdminUsersAdapter(mUsersList, AdminUsers.this);
lv_adminusersListContent.setAdapter(mUsersAdapter);
getUsersList();
}
private void getUsersList() {
if (UsefulFcts.isOnline(AdminUsers.this)) {
if (mThread != null && mThread.isAlive()) {
mThread.interrupt();
}
mThread = new Thread() {
@Override
public void run() {
mHandler.post(new Runnable() {
@Override
public void run() {
pDialog = new ProgressDialog(AdminUsers.this);
pDialog.setMessage("Loading.. Please wait!");
pDialog.setCancelable(false);
pDialog.show();
}
});
mUsersList.clear();
mUsersList.addAll(mServiceManager.getUsersList(mUserType,
0 + "", AdminServiceManager.sHowManyToLoad));
mArrayLength = mUsersList.size();
Log.d("arrayLength", String.valueOf(mArrayLength));
Log.d("total_results",
String.valueOf(ParserJSON.total_results));
mHandler.post(new Runnable() {
@Override
public void run() {
// refresh listview
mUsersAdapter.notifyDataSetChanged();
if (mArrayLength < ParserJSON.total_results) {
lv_adminusersListContent
.addFooterView(footerView);
} else if (mArrayLength >= ParserJSON.total_results) {
lv_adminusersListContent
.removeFooterView(footerView);
}
if (0 == mArrayLength) {
Toast.makeText(AdminUsers.this,
"No username found!",
Toast.LENGTH_SHORT).show();
}
pDialog.dismiss();
}
});
}
};
mThread.start();
} else {
Toast.makeText(AdminUsers.this, "Internet connection required!",
Toast.LENGTH_LONG).show();
}
}
@Override
protected void linkUI() {
// begin load_more view
footerView = AdminUsers.this.getLayoutInflater().inflate(
R.layout.loadmore, null);
btn_loadmore = (Button) footerView.findViewById(R.id.btn_loadmore);
// end load_more view
btn_adminusersViewall = (Button) findViewById(R.id.btn_adminusersViewall);
btn_adminusersAdmins = (Button) findViewById(R.id.btn_adminusersAdmins);
btn_adminusersClients = (Button) findViewById(R.id.btn_adminusersClients);
btn_adminusersDevs = (Button) findViewById(R.id.btn_adminusersDevs);
btn_adminAdd = (ImageButton) findViewById(R.id.btn_adminAdd);
lv_adminusersListContent = (ListView) findViewById(R.id.lv_adminusersListContent);
}
@Override
protected void setAction() {
// begin Buttons UnderHeader
btn_adminusersViewall.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
UsefulFcts.setButtonClicked(btn_adminusersViewall,
btn_adminusersClients, btn_adminusersAdmins,
btn_adminusersDevs);
mUserType = 0;
mArrayLength = -1;
lv_adminusersListContent.removeFooterView(footerView);
getUsersList();
}
});
btn_adminusersClients.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
UsefulFcts.setButtonClicked(btn_adminusersClients,
btn_adminusersDevs, btn_adminusersAdmins,
btn_adminusersViewall);
mUserType = 1;
mArrayLength = -1;
// view.setVisibility(View.GONE);
getUsersList();
}
});
btn_adminusersDevs.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
UsefulFcts.setButtonClicked(btn_adminusersDevs,
btn_adminusersClients, btn_adminusersAdmins,
btn_adminusersViewall);
mUserType = 2;
mArrayLength = -1;
lv_adminusersListContent.removeFooterView(footerView);
getUsersList();
}
});
btn_adminusersAdmins.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mUserType = 3;
mArrayLength = -1;
lv_adminusersListContent.removeFooterView(footerView);
getUsersList();
}
});
// end Buttons UnderHeader
btn_loadmore.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mThread2 = new Thread() {
@Override
public void run() {
mHandler.post(new Runnable() {
@Override
public void run() {
progressBar = new ProgressDialog(
AdminUsers.this);
progressBar
.setMessage("Loading more projects.. ");
progressBar.setCancelable(true);
progressBar.show();
}
});
mUsersList.addAll(mServiceManager.getUsersList(
mUserType, String.valueOf(mArrayLength),
AdminServiceManager.sHowManyToLoad));
mArrayLength = mUsersList.size();
mHandler.post(new Runnable() {
@Override
public void run() {
mUsersAdapter.notifyDataSetChanged();
if (mArrayLength >= ParserJSON.total_results) {
lv_adminusersListContent.removeFooterView(footerView);
}
progressBar.dismiss();
}
});
};
};
mThread2.start();
}
});
注意：我基本上有一个列表视图，根据我正在按下的按钮（看起来像一个选项卡）（mUserType = 0/1/2/3）从服务器请求内容。我还使用了加载更多按钮（footerView = 带有按钮的简单布局）。一切似乎都工作得很好，但是在“玩”了几次按钮（随机数！）之后，它崩溃了，并引发了以下异常：
02-21 11:00:49.252: E/AndroidRuntime(11728): java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. [in ListView(2131296461, class android.widget.ListView) with Adapter(class android.widget.HeaderViewListAdapter)]
因此，我回顾了代码，但看不到任何“不在 UI 线程上”的列表视图通知。
1.问题可能是什么？
2.是否有必要使用 2 个线程（mThread 和 mThread2），或者我可以使用同一个线程，因为一个人的工作应该在另一个结束时开始（或者不是吗？）我应该将它们声明为静态吗？
还指出我将来可以使用的任何“良好做法”技巧，或我所做的“错误做法”将不胜感激！
PS。linkUI() 和 setAction() 在 super().onCreate() 中调用。