我正在将进度条添加到我的活动中。我的目标是实现加载进度条，直到从Web获取数据。所以我在我的布局中编写了这些代码。
question_activity：
$delete_post = @$_POST['form-wallpostdelete']; //Form variable
if($delete_post) {
echo "Deleted";
}
?>
和QuestionActivity：
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.majid.whiteboard.activities.QuestionActivity">
<LinearLayout
android:id="@+id/linear_container_progress_question"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical"
android:visibility="gone">
<ProgressBar
android:id="@+id/prg_loading_question"
android:layout_width="50dp"
android:layout_height="50dp" />
</LinearLayout>
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar_question_activity"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="@color/colorPrimary"
app:titleTextColor="#fff" />
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_ac_question"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@id/toolbar_question_activity" />
</RelativeLayout>
我将xml中的LinearLayout设置为Visible.Gone，并将其设置为
中的活动 onCreate将其设置为@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_question);
initToolbar();
//Dialog initialization===========================================
final LinearLayout linearLayoutManagerProgressQuestion = (LinearLayout)findViewById(R.id.linear_container_progress_question);
linearLayoutManagerProgressQuestion.setVisibility(View.VISIBLE);
//Bundle Initialization =========================================
Bundle bundle = getIntent().getExtras();
if (bundle != null) {
faslId = bundle.getString("FASLID");
BaseUrl = bundle.getString("BASEURL");
}
//RecyclerView Initialization ======================================
recyclerQuestion = (RecyclerView) findViewById(R.id.recycler_ac_question);
recyclerQuestion.setHasFixedSize(true);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(QuestionActivity.this);
recyclerQuestion.setLayoutManager(linearLayoutManager);
adapterRecyclerQuestion = new AdapterRecyclerQuestion(QuestionActivity.this, questionha);
recyclerQuestion.setAdapter(adapterRecyclerQuestion);
// ========================== Sending FirstJsonRequest =================================
FirstUrl = BaseUrl + faslId;
JsonObjectRequest request = new JsonObjectRequest(FirstUrl, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
if (response != null || response.length() > 0) {
try {
JSONArray data = response.getJSONArray("data");
for (int i = 0; i < data.length(); i++) {
JSONObject currentData = data.getJSONObject(i);
ModelQuestion newModelQuestion = new ModelQuestion();
newModelQuestion.setQuestionDate(currentData.getString("date"));
newModelQuestion.setQuestionDownFileName(currentData.getString("filename"));
questionha.add(newModelQuestion);
}
afterUrl = response.getString("pagination");
} catch (JSONException e) {
e.printStackTrace();
}
adapterRecyclerQuestion.notifyDataSetChanged();
linearLayoutManagerProgressQuestion.setVisibility(View.GONE);
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
linearLayoutManagerProgressQuestion.setVisibility(View.GONE);
}
});
AppController.getInstance().addToRequestQueue(request);
并在adapter.notifyDataSetChanged（）
到View.VISIBLE。在棒棒糖前设备中，每件事都是View.Gone，但是进步
在Lollipop设备中不显示。