加载指示符

heyblood · Jan 26, 2021 · d837afe · d837afe
1 parent 6a693e5
commit d837afe
Show file tree

Hide file tree

Showing 2 changed files with 15 additions and 1 deletion.
diff --git a/app/src/main/java/com/example/quakereport/EarthquakeActivity.java b/app/src/main/java/com/example/quakereport/EarthquakeActivity.java
@@ -22,6 +22,7 @@
 import android.view.View;
 import android.widget.AdapterView;
 import android.widget.ListView;
+import android.widget.ProgressBar;
 import android.widget.TextView;
 
 import androidx.annotation.NonNull;
@@ -49,7 +50,7 @@ public class EarthquakeActivity extends AppCompatActivity implements LoaderManag
      * URL for earthquake data from the USGS dataset
      */
     private static final String USGS_REQUEST_URL =
-            "https://earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&orderby=time&minmag=5&limit=0";
+            "https://earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&orderby=time&minmag=5&limit=15";
 
     /**
      * 地震列表的适配器
@@ -127,6 +128,10 @@ public void onLoadFinished(@NonNull Loader<List<Earthquake>> loader, List<Earthq
         // Set empty state text to display "No earthquakes found."
         emptyView.setText(R.string.no_earthquakes);
 
+        // 因数据已加载，隐藏加载指示符
+        ProgressBar progressBar = findViewById(R.id.loading_spinner);
+        progressBar.setVisibility(View.GONE);
+
         // 清除之前地震数据的适配器
         earthquakeAdapter.clear();
 

diff --git a/app/src/main/res/layout/earthquake_activity.xml b/app/src/main/res/layout/earthquake_activity.xml
@@ -19,4 +19,13 @@
         android:layout_height="wrap_content"
         android:layout_centerInParent="true"
         android:textAppearance="?android:textAppearanceMedium" />
+
+    <!-- Loading spinner is only shown before the first load -->
+    <ProgressBar
+        android:id="@+id/loading_spinner"
+        style="?android:progressBarStyle"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_centerInParent="true" />
+
 </RelativeLayout>