I have a ListView where I until today have positioned two views: One ImageView to the left of its parent, and then I use a TextView positioned just to the right of this ImageView. In xml I use the following code to do that:
android:layout_toRightOf="@+id/single" , where single is an ImageView.
... so no problem whatsoever :-)
But today I came up with a new idea - that i want another ImageView in this ListView. I positioned this new view to the right side of its parent (ListView).
android:layout_alignParentRight="true"
Now a small problem arised when I did this: In cases where I have a long sentence in the TextView it overlappes this new ImageView. But according to the android documentation I found this code:
android:layout_toStartOf="@+id/volume" , where volume is the id for the new ImageView.
I really thought it would work. to the end of means Positions the end edge of this view to the start of the given anchor view ID. [reference]
So I thought everthing would work but when I compiled and started to test the app my app crashes when a listview i clicked. The crash is due to classcastexception. ImageView cannot be cast to TextView
So my question is why I get this ClassCastException? The only thing I do is to postion the end edge of the TextView to the start of the ImageView. Why do I get a classcastException when I use toStartOf? I do not get an exception when I position the TextView to the right of the other ImageView , using the xml-code android:layout_toRightOf="@+id/single"
In summary: my goal is to have three views in this ListView: two ImageView - one to the left and one to the right. And in between of these two ImageViews I want to place the TextView.
I get the exception in the getChildView-method.
<!-- Layout för undermenyerna -->
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="5dp"
android:paddingLeft="0px"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="0px"
android:background="#ffffff"
tools:context=".PhraseActivity" >
<!-- view för ena ena könet, man eller kvinna -->
<TextView
android:id="@+id/label_single"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_toRightOf="@+id/single"
android:layout_toStartOf="@+id/volume"
android:la
/>
<!-- texview för båda könen, man och kvinna -->
<TextView
android:id="@+id/label_couple"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_toRightOf="@+id/couple"
/>
<!-- texview för extra info -->
<TextView
android:id="@+id/extra_info"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/couple"
android:layout_marginTop="10sp"
android:background="@drawable/back_extrainfo"
android:padding="5sp"
android:visibility="gone"
android:textColor="#8c8c8c"
/>
<!-- text länk till bild, tex karta som visar vart staden är i Thailand -->
<TextView
android:id="@+id/imagelink"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:focusableInTouchMode="true"
android:text="Click to view on map"
android:textColor="#3241d3"
android:layout_centerHorizontal="true"
android:layout_below="@+id/couple"
/>
<!-- text länk till bild, samma syfte som texviewen ovan -->
<TextView
android:id="@+id/imagelink2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:text="Click to view image"
android:focusableInTouchMode="true"
android:textColor="#3241d3"
android:layout_centerHorizontal="true"
android:layout_below="@+id/extra_info"
/>
<!-- view för en bild av ena könet, man eller kvinna -->
<ImageView
android:id="@+id/single"
android:layout_width="68sp"
android:layout_height="68sp"
/>
<!-- view för en bild av båda könen, man och kvinna -->
<ImageView
android:id="@+id/couple"
android:layout_width="100sp"
android:layout_height="68sp"
/>
<ImageView
android:id="@+id/volume"
android:layout_width="100sp"
android:layout_height="79sp"
android:layout_alignParentRight="true"
/>
</RelativeLayout>
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.activity_subphrase, parent, false);
holder = new ViewHolder();
holder.text = (TextView) convertView.findViewById(R.id.label_single);
holder.text2 = (TextView) convertView.findViewById(R.id.label_couple);
holder.imageView = (ImageView) convertView.findViewById(R.id.single);
holder.imageView2 = (ImageView) convertView.findViewById(R.id.couple);
holder.volumeControl = (ImageView) convertView.findViewById(R.id.volume);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final int nChildren = getChildrenCount(groupPosition);
final View v = convertView;
switch (nChildren) {
case 1:
holder.imageView.setBackgroundResource(0);
holder.imageView2.bringToFront();
holder.imageView2.setVisibility(ImageView.VISIBLE);
holder.text.setText(null);
holder.text2.setText(contents[groupPosition][childPosition]);
holder.imageView2.setBackgroundResource(R.drawable.man_woman_3);
//extra(groupPosition, category, holder.text, convertView, parent);
showThaiImages(groupPosition, holder.text, convertView, parent);
// Väntar till all layout är avklarad - efter detta bearbetas animering.
vto = convertView.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
public void onGlobalLayout() {
v.getViewTreeObserver().removeOnGlobalLayoutListener(this); //vet inte om denna metod är nödvändig
holder.imageView2.bringToFront();
holder.imageView2.setBackgroundResource(R.drawable.animation3);
frameAnimation = (AnimationDrawable) holder.imageView2.getBackground();
frameAnimation.start();
}});
break;
case 2:
try {
System.out.println("ViewTreeObserver is alive = : " + vto.isAlive());
} catch (Exception e) {
e.printStackTrace();
}
//v.getViewTreeObserver().removeOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener()); //vet inte om denna metod är nödvändig
holder.imageView2.setVisibility(View.GONE);
holder.imageView2.setBackgroundResource(0);
holder.imageView.bringToFront();
holder.text2.setText(null);
//holder.imageView.invalidate();
holder.text.setText(contents[groupPosition][childPosition]);
switch (childPosition) { // Switch-villkor för man eller kvinna.
case 0: // Man.
holder.imageView.setBackgroundResource(R.drawable.man_3);
break;
case 1: // Kvinna.
holder.imageView.setBackgroundResource(R.drawable.woman_3);
break;
}
break;
}
holder.volumeControl.setBackgroundResource(R.drawable.speaker);
notifyDataSetChanged();
return convertView;
}