我有AsyncTask正在做一些背景“工作”。
在ProgressBar和onPreExecute中实施onPostExecute，相应地更改了可见性。
但我无法看到ProgressBar。完成工作后屏幕会冻结几秒钟，然后活动会加载数据。
我通过改变ProgressBar的背景颜色进行测试，当改变bgcolor（告诉ProgressBar在那里）时，我可以看到ProgressBar为方形黑色视图，但这不是要求。
我如何看到ProgressBar的微调器，我也发布了我的布局代码，以防万一有错：
xml：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.CoordinatorLayout
android:id="@+id/coor"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#f4f4f4"
android:fitsSystemWindows="true"
tools:context="com.example.svatts.my22.ScrollingActivity">
<android.support.design.widget.AppBarLayout
android:id="@+id/app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="80dp"
android:fitsSystemWindows="true"
app:contentScrim="?android:attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<!--
// image view was here-->
<TextView
android:id="@+id/userName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="20dp"
android:paddingTop="20dp"
android:textColor="#000"
android:textSize="20sp"
app:layout_collapseMode="parallax" />
</android.support.design.widget.CollapsingToolbarLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingBottom="10dp">
<ImageView
android:id="@+id/fbdp"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginBottom="10dp"
android:layout_marginLeft="20dp"
android:layout_marginTop="10dp"
/>
<TextView
android:id="@+id/month"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginTop="20dp"
android:layout_toRightOf="@+id/fbdp"
android:fontFamily="cursive"
android:text="December ' 16"
android:textColor="#000"
android:textSize="15sp" />
<TextView
android:id="@+id/amt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/month"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"
android:layout_toRightOf="@+id/fbdp"
android:textColor="#000"
android:textSize="20sp"
android:textStyle="bold" />
</RelativeLayout>
<!--need to change the background as an object oval prbbly-->
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_scrolling" />
</android.support.design.widget.CoordinatorLayout>
<ProgressBar
android:id="@+id/loadingBar"
style="@style/Widget.AppCompat.ProgressBar"
android:layout_width="42dp"
android:layout_height="42dp"
android:layout_gravity="center"
android:theme="@style/CircularProgress"
android:visibility="visible" />
</FrameLayout>
AsyncTask：
public class ReadingSMS extends AsyncTask<String, String, Cursor> {
protected void onPreExecute() {
mLoadingIndicator.setVisibility(View.VISIBLE);
}
@Override
protected void onPostExecute(Cursor result) {
run(result);
mLoadingIndicator.setVisibility(View.INVISIBLE);
}
@Override
protected Cursor doInBackground(String... params) {
return refreshSmsInbox();
}
}
}
CircularProgress风格：
<style name="CircularProgress" parent="Theme.AppCompat.Light">
<item name="colorAccent">@color/colorFAB2</item>
</style>
run（）方法：
@Override
public void run(Cursor result) {
int indexDate = result.getColumnIndex("date");
int indexBody = result.getColumnIndex("body");
do {
// String str = "SMS From: " + smsInboxCursor.getString(indexAddress) +
// "\n" + smsInboxCursor.getString(indexBody) + "\n";
// arrayAdapter.add(str);
if (!stopReading) {
Date date = new Date(Long.parseLong(result.getString(indexDate)));
String newDate = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss").format(date);
//DateTime fmt = DateTime.parse(date.toString(),DateTimeFormat.forPattern("EEE MMM dd HH:mm:ss z yyyy"));
//String formattedDate = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy").format(date);
// Toast.makeText(this,newDate,Toast.LENGTH_SHORT).show();
Transaction tr = new Transaction(ScrollingActivity.this);
if (tr.isTransaction(result.getString(indexBody))) {
Log.d("here now bro", "yea");
tr.msg = result.getString(indexBody);
tr.date = newDate;
tr.call(ScrollingActivity.this);
}
}
} while (result.moveToNext());
////////////////////////////////
trList = new ArrayList<Transaction>();
// trList = new Transaction(this).getTransactions(); // getting transactions from pythonanywhere server
trList = new Transaction(this).getTransactionsFromSQLite();
Transaction.transactionList = trList;
getPreviousMonthsInfo(trList);
updateBarChart(expenses);
Log.d("gettingVals", "yooyyo");
setRecentTrans();
TextView month = (TextView) findViewById(R.id.month);
month.setText(monthNames[0] + "-" + currentYear);
month.setTypeface(sansation);
TextView amt = (TextView) findViewById(R.id.amt);
month.setTypeface(sansation);
amt.setText("₹ " + expenses[0]);
TextView recentHeading = (TextView) findViewById(R.id.recentHeading);
month.setTypeface(sansation);
TextView graphHeading = (TextView) findViewById(R.id.graphHeading);
month.setTypeface(sansation);
setBalances();
}