Collapsible Tree List for Android
###Building Build the library (compiles to library/build/outputs/aar/library.aar) :
$ ./gradlew :library:assembleRelease Build and install the sample:
$ ./gradlew :sample:assembleDebug
$ adb install -r sample/build/outputs/apk/sample-debug.apk###Usage
####Add The ListView Canopy operates on a standard ListView.
public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView list = (ListView) findViewById(R.id.comments_list);
// rootComment is an object that implements CanopyItem
// (see the next section)
CanopyAdapter adapter = new CanopyAdapter(this, rootComment);
CanopyItemClickListenr listener = new CanopyItemClickListenr(adapter);
list.setAdapter(adapter);
list.setOnItemClickListener(listener);
// ...
}
// ...
}####Implement CanopyItem The easiest way to implement CanopyItem is to extend BaseCanopyItem in your model.
public class Comment extends BaseCanopyItem {The constructor should take a List of children, and the depth of this node.
public Comment(List<CanopyItem> children, int depth, ...) {
super(true, true, depth, children);
// ...
}Finally, you should override getExpandedView and getCollapsedView.
@Override
public void getExpandedView(LayoutInflater inflater, ViewGroup parent) {
CanopyRowView canopyRow =
(CanopyRowView) super.getExpandedView(inflater, parent);
LinearLayout content = canopyRow.getContentLayout();
// Here, expand your views and add them to the content view
content.addView(myContent);
return canopyRow;
}
@Override
public void getCollapsedView(LayoutInflater inflater, ViewGroup parent) {
// Handle the same as above
}####Changing Depth Indicator Colors Canopy handles level indicator colors with the ColorProvider interface. To change the colors that are displayed, override getColorProvider in your model with either a class that implements ColorProvider, or anonymously.
@Override
public ColorProvider getColorProvider() {
return new ColorProvider() {
@Override
public int getColor(int depth) {
// Return red for even depths, blue for odd
if (depth % 2 == 0) {
return Color.RED;
} else {
return Color.BLUE;
}
}
}
}