我的应用中存在问题。这是一本电话簿。使用AsyncTask后,所有颜色都会改变!
这是使用AsyncTask前的截图:
这是使用AsyncTask后的屏幕截图:
我的应用程序出了什么问题?
1: 我的代码(使用AsyncTask):
public class MainActivity extends Activity {
ArrayList<Contact> contacts;
private ContactAdapter contactAdapter;
private DbWorker db;
private ListView listView;
private Context context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listview);
context = getApplicationContext();
new DbAsyncTask(context).execute();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent = new Intent(MainActivity.this, ChangeContactActivity.class);
Contact contact = contactAdapter.getContact(position);
intent.putExtra("name", contact.getContactName());
intent.putExtra("phone", contact.getContactPhone());
intent.putExtra("category", contact.getContactCategory());
intent.putExtra("org", contact.getContactOrgName());
intent.putExtra("id", contact.getContactId());
startActivity(intent);
}
});
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, AddContactActivity.class);
startActivity(intent);
}
});
}
class DbAsyncTask extends AsyncTask<Void, Void, ArrayList<Contact>> {
private Context ctx;
public DbAsyncTask(Context ctx){
this.ctx = ctx;
}
@Override
protected ArrayList<Contact> doInBackground(Void... params) {
db = new DbWorker(ctx);
contacts = (ArrayList<Contact>) db.selectAllContacts();
return contacts;
}
@Override
protected void onPostExecute(ArrayList<Contact> contacts) {
contactAdapter = new ContactAdapter(ctx, contacts);
listView.setAdapter(contactAdapter);
}
}
}
没有AsyncTask我提交:
listView = (ListView) findViewById(R.id.listview);
context = getApplicationContext();
new DbAsyncTask(context).execute();
并添加:
db = new DbWorker(this);
listView = (ListView) findViewById(R.id.listview);
contacts = (ArrayList<Contact>) db.selectAllContacts();
contactAdapter = new ContactAdapter(this, contacts);
listView.setAdapter(contactAdapter);
答案 0 :(得分:0)
您正在将应用程序的上下文传递给您的异步,该异步没有关于您的主题/样式的线索。相反,您应该使用具有所需主题/样式信息的活动上下文。
因此,替换:
cfoutput
以下内容:
context = getApplicationContext();