【发布时间】：2013-05-26 19:48:52
【问题描述】：
如何在可展开视图中为各个组名设置不同的背景颜色？
我有使用组名创建组的代码 - 组 1 到组 10。每个组都有孩子 - 孩子 1 到孩子 3。
我想根据组名为每个组及其子项赋予不同的背景颜色。如果条件不满足，则默认为黑色。
示例：
第 1 组 - 白色背景
第 2 组 - 红色背景
第 3 组 - 灰色背景
第 4 组 - 黄色背景
main.XML：可扩展列表布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<ExpandableListView
android:id="@+id/expandable_list"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<ListView
android:id="@+id/android:list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:choiceMode="multipleChoice" />
</LinearLayout>
grouprow.xml：组文本布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:id="@+id/rowname"
android:paddingLeft="50px"
android:textSize="30px"
android:textColor="@drawable/blue"
android:textStyle="normal"
android:layout_width="fill_parent"
android:layout_height="50px"/>
</LinearLayout>
childrow.xml：子文本布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TextView android:id="@+id/grpchild"
android:paddingLeft="50px"
android:focusable="false"
android:textSize="14px"
android:textStyle="normal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
父组类：类来创建每个父项
public class CategoryGroup {
private String mTitle;
private ArrayList<String> mArrayChildren;
public String getTitle() {
return mTitle;
}
public void setTitle(String mTitle) {
this.mTitle = mTitle;
}
public ArrayList<String> getArrayChildren() {
return mArrayChildren;
}
public void setArrayChildren(ArrayList<String> mArrayChildren) {
this.mArrayChildren = new ArrayList(mArrayChildren);
}
}
可扩展列表类：
public class ExpandableListItems extends BaseExpandableListAdapter {
private LayoutInflater inflater;
private ArrayList<CategoryGroup> mParent;
public ExpandableListItems(Context context, ArrayList<CategoryGroup> parent) {
mParent = parent;
inflater = LayoutInflater.from(context);
}
@Override
//counts the number of group/parent items so the list knows how many times calls getGroupView() method
public int getGroupCount() {
return mParent.size();
}
@Override
//counts the number of children items so the list knows how many times calls getChildView() method
public int getChildrenCount(int i) {
return mParent.get(i).getArrayChildren().size();
}
@Override
//gets the title of each parent/group
public Object getGroup(int i) {
return mParent.get(i).getTitle();
}
@Override
//gets the name of each item
public Object getChild(int i, int i1) {
return mParent.get(i).getArrayChildren().get(i1);
}
@Override
public long getGroupId(int i) {
return i;
}
@Override
public long getChildId(int i, int i1) {
return i1;
}
@Override
public boolean hasStableIds() {
return true;
}
@Override
//in this method you must set the text to see the parent/group on the list
public View getGroupView(int i, boolean b, View view, ViewGroup viewGroup) {
if (view == null) {
System.out.println("i: " + i + "; b: " + b );
view = inflater.inflate(R.layout.grouprow, viewGroup, false);
}
TextView textView = (TextView) view.findViewById(R.id.rowname);
//"i" is the position of the parent/group in the list
textView.setText(getGroup(i).toString());
//return the entire view
return view;
}
@Override
//in this method you must set the text to see the children on the list
public View getChildView(int i, int i1, boolean b, View view, ViewGroup viewGroup) {
if (view == null) {
view = inflater.inflate(R.layout.childrow, viewGroup, false);
}
TextView textView = (TextView) view.findViewById(R.id.grpchild);
//"i" is the position of the parent/group in the list and
//"i1" is the position of the child
textView.setText(mParent.get(i).getArrayChildren().get(i1));
//return the entire view
return view;
}
@Override
public boolean isChildSelectable(int i, int i1) {
return true;
}
@Override
public void registerDataSetObserver(DataSetObserver observer) {
/* used to make the notifyDataSetChanged() method work */
super.registerDataSetObserver(observer);
}
}
主 Activity 类：
public class GetResourcesListActivity extends ListActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
private ExpandableListView mExpandableList;
private ExpandableListItems mAdapter;
ArrayList<CategoryGroup> arrayParentsGroups = new ArrayList<CategoryGroup>();
mExpandableList = (ExpandableListView)findViewById(R.id.expandable_list);
arrayParents = createGroupList();
mAdapter = new ExpandableListItems(this, arrayParentsGroups);
mExpandableList.setAdapter(mAdapter);
private List createGroupList() {
ArrayList arrayParents = new ArrayList();
for( int i = 0 ; i < 10 ; ++i ) { // 10 groups........
CategoryGroup parent = new CategoryGroup();
parent.setTitle("Group" + i);
ArrayList<String> arrayChildren = new ArrayList<String>();
for (int j = 0; j < 3; j++) {
arrayChildren.add("Child " + j);
}
parent.setArrayChildren(arrayChildren);
arrayParents.add(parent);
}
return arrayParents;
}
}
)
【问题讨论】：