我有一个Android活动为基本活动具有以下布局 -Android的基本活动和ListView控件 - 进度条不可见
而且下面是布局
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_read_contacts"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="au.com.savedme.ReadContacts">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/readContactLv" />
<ProgressBar
style="?android:attr/progressBarStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/readContactPb"
android:layout_alignParentBottom="false"
android:layout_alignParentRight="false"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
app:fabSize="mini"
app:srcCompat="@mipmap/ic_cloud_upload_white_24dp"
android:id="@+id/readContactFab"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true" />
的XML
我从其他活动开始此活动。我的目标是让进度条在onCreate方法中可见,然后加载列表视图,一旦列表视图填充了我想让进度条不可见的项目。
我的问题是
- 如果我开始填充列表查看进度条是不可见的,在所有的不管是什么我试试。
- 如果我跳过填充列表视图,进度条清晰可见。
- 如果我正在填充列表视图,从前一个活动导航显着延迟,并且屏幕冻结并变黑(和空白),并且一旦列表填充,它就会返回,这不会给出任何视觉线索给用户一些事情发生(不需要)。
我应该怎么做才能防止这种情况,下面是我的onCreate方法 -
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_read_contacts);
pb = (ProgressBar) findViewById(R.id.readContactPb);
pb.setVisibility(View.VISIBLE);
// Variable initialisations
contactList = new ArrayList<>();
contactListTosave = new ArrayList<>();
mDatabase = FirebaseDatabase.getInstance().getReference();
userId = FirebaseAuth.getInstance().getCurrentUser().getUid();
mContactListView = (ListView) findViewById(R.id.readContactLv);
mContactListView.setOnItemClickListener(onClickListener);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.readContactFab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
for (Contact contactToSave:contactListTosave){
mDatabase.child("contacts").child(userId).child(contactToSave.getFirstName()).setValue(contactToSave);
}
Intent i = new Intent(getApplicationContext(),ContactList.class);
startActivity(i);
}
});
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
if (mAdapter == null) {
mAdapter = new ContactArrayAdapter(ReadContacts.this, 0, contactList);
mContactListView.setAdapter(mAdapter);
}
checkPermissionToReadContact();
}
而下面是我listAdapter代码 -
import android.content.Context;
import android.os.Build;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
/**
* Created by AppsWise on 15/10/16.
*/
public class ContactArrayAdapter extends ArrayAdapter<Contact> {
private Context context;
private List<Contact> contactsProperties;
private String TAG = "ContactArrayAdapter";
//constructor, call on creation
public ContactArrayAdapter(Context context, int resource, ArrayList<Contact> objects) {
super(context, resource, objects);
this.context = context;
this.contactsProperties = objects;
}
// Called when rendering the view
public View getView(int position, View convertView, ViewGroup parent) {
// get properties we are displaying
Contact contact = contactsProperties.get(position);
//Get inflater and inflate the XML layout for each item
LayoutInflater inflater = (LayoutInflater) context.getSystemService(MainActivity.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.contact_item, null);
TextView nameText = (TextView) view.findViewById(R.id.nameText);
TextView contactName = (TextView) view.findViewById(R.id.contactName);
TextView number = (TextView) view.findViewById(R.id.phoneText);
String completeName = "";
if(contact.getFirstName()!=null){
completeName = contact.getFirstName();
}
if(contact.getLastName()!=null){
completeName += " "+contact.getLastName();
}
if (completeName!=null && completeName.trim().length()>0) {
if (nameText!=null) {
nameText.setText(completeName.substring(0,1).toUpperCase());
}
contactName.setText(completeName);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && contact.getIsUploaded()){
nameText.setBackgroundColor(context.getColor(R.color.colorAccent));
}
}
number.setText(contact.getPhone());
return view;
}
}
可以显示你的XML文件 – Vadivel
在适配器类中创建一个接口,当适配器工作完成后,使用此接口将完成状态传递给activity.then您可以停止该回调中的进度 – Ak9637
@ Ak9637对不起,我没有明白,请问在适配器类中解释更多关于创建接口的信息? –