My issue: In my xml file, I define android:visibility="gone" in the linear layout labelled as assess_layout_list. Then, in the onClick() of course_adapter_layout, the whole view, I set the visibility back to View.VISIBLE, which does not work, even though the Log call just before it works, the LinearLayout object called assess_list_layout is not null, and it does work when I define the visibility="invisible" in the xml file. I want it to be gone at first though, and visible after clicking as this fits the design of the app.
Here is my course_adapter_view.xml file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@ id/course_adapter_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="left"
>
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginHorizontal="20dp"
android:layout_marginTop="20dp"
android:padding="15dp"
android:elevation="2dp"
android:background="@drawable/course_header_background">
<ImageView
android:layout_width="20dp"
android:layout_height="20dp"
android:src="@drawable/course_color_circle"/>
<Space
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="0.25"/>
<TextView
android:id="@ id/course_adapter_course_code"
android:text="TextView1"
android:layout_width="wrap_content"
android:layout_height="20dp"
android:layout_weight="0.5"/>
<Space
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="0.25"/>
<TextView
android:id="@ id/course_adapter_course_title"
android:text="TextView2"
android:layout_width="wrap_content"
android:layout_height="20dp"/>
</LinearLayout>
<LinearLayout
android:id="@ id/assess_list_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginRight="40dp"
android:layout_marginLeft="40dp"
android:background="@drawable/course_body_background"
android:padding="20dp"
android:visibility="gone"
>
<ListView
android:id="@ id/course_adapter_assess_list"
android:layout_width="match_parent"
android:layout_height="250dp"
android:layout_marginBottom="10dp"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:text="More" />
<Space
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:text="New"/>
</LinearLayout>
</LinearLayout>
</LinearLayout>
Here is my CourseListAdapter.java file that I use to create each view for each course in the list of courses, minus the usual stuff:
@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
// get info
String course_code = getItem(position).getCourseCode();
Double course_grade = getItem(position).getCurrentGrade();
// make inflater and inflate the layout
LayoutInflater inflater = LayoutInflater.from(context);
View v = inflater.inflate(mResource, parent, false);
TextView tv_course_code = v.findViewById(R.id.course_adapter_course_code);
TextView tv_course_title = v.findViewById(R.id.course_adapter_course_title);
tv_course_code.setText(course_code);
tv_course_title.setText(String.valueOf(course_grade));
// add on click to each list view element
LinearLayout layout = v.findViewById(R.id.course_adapter_layout);
layout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.i(TAG, "List view element has been clicked " course_code);
// expand the view to include a new fragment
LinearLayout assess_list_layout = view.findViewById(R.id.assess_list_layout);
assess_list_layout.setVisibility(View.VISIBLE);
// get the list view and add each course to the course view
ListView assessment_list_view = (ListView) view.findViewById(R.id.course_adapter_assess_list);
AssessmentListAdapter assessAdapter = new AssessmentListAdapter(getContext(), R.layout.assessment_adapter_view, getItem(position).getAssessmentList(), getItem(position));
assessment_list_view.setAdapter(assessAdapter);
}
});
return v;
}
}
Please let me know if there is any more information you need. Will also take suggestions on other ways of accomplishing the same thing. Thanks for your help. ~Seth.
Edit: when the assess_list_layout.setVisibility(View.VISIBLE) is outside of the onClick it does work.
Further Edit: Things I have tried so far to no avail:
- moving the location of where I define the LinearLayout componenent
- calling invalidate() on parent view
- using runOnUiThread()
CodePudding user response：
You have founded the resource id of assess_list_layout linearlayout wrong,
Currently your have
LinearLayout assess_list_layout = view.findViewById(R.id.assess_list_layout);
Where view is the view of onCLick, and not your parent layout.
Update it to,
LinearLayout assess_list_layout = v.findViewById(R.id.assess_list_layout);
Here v is view of your parent layout
Same goes for your assessment_list_view
CodePudding user response：
LinearLayout assess_list_layout = view.findViewById(R.id.assess_list_layout);
assess_list_layout.setVisibility(View.VISIBLE);
keep this in globally than its work, no need to use View.VISIBLE, Keep the variable unique
Don't use this in your XML, because it gets confused.
android:visibility="gone"
Note: If you put the code making an element visible into its onClickListener, it won't be reachable (if it consumes none of the screen space, you won't be able to click on it). You should put a layout with a minimal height below it, and when your view l becomes gone, the new layout shell becomes visible, and it should get the visible-making onClickListener. This way, after your View becomes gone, this new layout will be able to bring it back.