- How to combine check box to "filter"
ListView
elements. - Sending a
Parcelable
object or a list ofParcelable
objects throughIntent
. - Adding many view elements to a
ViewGroup
.
Now, Let's start an Android project!
Defining a
Friend
object for use. Implement Parcelable
to put through Intent
later. Friend.java
source code may be like this:
Friend.java
Next, we will create public class Friend implements Parcelable {
private boolean gender;
private String name;
private boolean isSelected;
/**
* Create parcelable of friend
*/
public static final Parcelable.Creator<Friend> CREATOR = new Parcelable.Creator<Friend>() {
public Friend createFromParcel(Parcel in) {
return new Friend(in);
}
public Friend[] newArray(int size) {
return new Friend[size];
}
};
/**
* Create Friend from Parcel object.
*
* @param in
*/
public Friend(Parcel in) {
this.name = in.readString();
this.gender = in.readByte() != 0;
this.isSelected = in.readByte() != 0;
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(this.name);
dest.writeByte((byte) (this.gender ? 1 : 0));
dest.writeByte((byte) (this.isSelected ? 1 : 0));
}
public Friend(String name, boolean gender) {
this.name = name;
this.gender = gender; // true is male, false is woman
this.isSelected = false; // not selected when create
}
public boolean isGender() {
return gender;
}
public void setGender(boolean gender) {
this.gender = gender;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public boolean isSelected() {
return isSelected;
}
public void setSelected(boolean isSelected) {
this.isSelected = isSelected;
}
}
MainActivity
. In this, we have some important methods:-
setListViewHeader()
: add header forListView
, click at this header button, we will go toSelectedListActivity
contain all friends which checked. -
setAdapterData
): provide data forListView
. - Handling event for "Go to selected list" button.
Source code:
MainActivity.java
And this is public class MainActivity extends Activity {
private ListView listView;
private View btnList;
private ArrayList<Friend> friends;
private ListViewAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.list_view);
setListViewHeader();
setListViewAdapter();
setAdapterData();
btnList.setOnClickListener(gotoSelectedListActivity()); // go to checked list
}
/**
* set listview footer method
*/
private void setListViewHeader() {
LayoutInflater inflater = getLayoutInflater();
ViewGroup header = (ViewGroup) inflater.inflate(
R.layout.header_listview, listView, false);
listView.addHeaderView(header, null, false);
btnList = (Button) findViewById(R.id.button);
}
private void setListViewAdapter() {
friends = new ArrayList<Friend>();
adapter = new ListViewAdapter(this, R.layout.item_listview, friends);
listView.setAdapter(adapter);
}
private void setAdapterData() {
friends.add(new Friend("Harry Brown", true));
friends.add(new Friend("Nguyen Tuan Anh", true));
friends.add(new Friend("Rin Zuzuki", false));
friends.add(new Friend("Zheng Lee", true));
friends.add(new Friend("Ana Olenhina", false));
friends.add(new Friend("Nhat Trang", false));
friends.add(new Friend("Mai Phuong", false));
friends.add(new Friend("Yasmin Abdulaziz", false));
friends.add(new Friend("Park Ji Won", true));
adapter.notifyDataSetChanged(); // update adapter
}
/**
* handle footer listview button event
* @return
*/
private OnClickListener gotoSelectedListActivity() {
return new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, SelectedListActivity.class);
intent.putParcelableArrayListExtra("Checked List", friends);
startActivity(intent);
}
};
}
}
activity_main.xml
file for layout:<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="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.blogspot.hongthaiit.listviewwithcheckbox.MainActivity" >
<ListView
android:id="@+id/list_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="none" >
</ListView>
</RelativeLayout>
As already mentioned above, we must create SelectedListActivity
to show selected elements. In this activity, I will present the way to add many elements to a LinearLayout
in generateDataToContainerLayout()
method. Full file source code:
SelectedListActivity.java
Other work is creating a public class SelectedListActivity extends Activity {
private LinearLayout container;
private ArrayList<Friend> checkedList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list);
container = (LinearLayout) findViewById(R.id.layout);
checkedList = new ArrayList<Friend>(); // initializing list
getDataFromIntent(); // receive data from intent (put by MainActivity)
generateDataToContainerLayout();
}
private void getDataFromIntent() {
checkedList = getIntent().getParcelableArrayListExtra("Checked List");
Log.i("ListActivity", "size" + checkedList.size());
}
@SuppressLint("InflateParams")
private void generateDataToContainerLayout() {
int i = 0;
if (checkedList.size() == i) { //do nothing
}
while (checkedList.size() > i) {
final Friend friend = checkedList.get(i);
LayoutInflater inflater = (LayoutInflater) getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.item_listview, null,
false);
ImageView genderImage = (ImageView) view.findViewById(R.id.gender);
TextView friendName = (TextView) view.findViewById(R.id.name);
CheckBox checked = (CheckBox)view.findViewById(R.id.check);
checked.setVisibility(View.GONE);
if (friend.isSelected()) {
Log.i("ListActivity", "here" + friend.getName());
friendName.setText(friend.getName());
if (friend.isGender()) {
genderImage.setImageResource(R.drawable.male);
} else {
genderImage.setImageResource(R.drawable.female);
}
// add view after all
container.addView(view);
}
i++; // rise i
}
}
}
ListView
adapter. We should extend ArrayAdapter
, not BaseAdapter
, it's more convenient:
ListViewAdapter.java
And these are some xml files we need:public class ListViewAdapter extends ArrayAdapter<Friend> {
private Activity activity;
private ArrayList<Friend> Friends;
private final String TAG = ListViewAdapter.class.getSimpleName();
public ListViewAdapter(Activity activity, int resource, ArrayList<Friend> Friends) {
super(activity, resource, Friends);
this.activity = activity;
this.Friends = Friends;
Log.i(TAG, "init adapter");
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
// inflate layout from xml
LayoutInflater inflater = (LayoutInflater) activity
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
// If holder not exist then locate all view from UI file.
if (convertView == null) {
// inflate UI from XML file
convertView = inflater.inflate(R.layout.item_listview, parent, false);
// get all UI view
holder = new ViewHolder(convertView);
// set tag for holder
convertView.setTag(holder);
} else {
// if holder created, get tag from view
holder = (ViewHolder) convertView.getTag();
}
Friend friend = Friends.get(position);
//set Friend data to views
holder.name.setText(friend.getName());
if (friend.isGender()) {
holder.image.setImageDrawable(this.activity.getResources()
.getDrawable(R.drawable.male));
} else {
holder.image.setImageDrawable(this.activity.getResources()
.getDrawable(R.drawable.female));
}
//set event for checkbox
holder.check.setOnCheckedChangeListener(onCheckedChangeListener(friend));
return convertView;
}
/**
* handle check box event
* @param f
* @return
*/
private OnCheckedChangeListener onCheckedChangeListener(final Friend f) {
return new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
f.setSelected(true);
} else {
f.setSelected(false);
}
}
};
}
private class ViewHolder {
private ImageView image;
private TextView name;
private CheckBox check;
public ViewHolder(View v) {
image = (ImageView) v.findViewById(R.id.gender);
name = (TextView) v.findViewById(R.id.name);
check = (CheckBox) v.findViewById(R.id.check);
}
}
}
-
activity_list.xml
(Layout for SelectedActivity.java
):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#666666"
android:layout_marginTop="10dp"
android:textColor="@android:color/white"
android:text="@string/ckecked" />
<LinearLayout
android:id="@+id/layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</LinearLayout>
- item_listview.xml
(Layout for each ListView
row):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<CheckBox
android:id="@+id/check"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.1" />
<ImageView
android:id="@+id/gender"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.35"
android:contentDescription="@string/action_settings" />
<TextView
android:id="@+id/name"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.45"
android:textColor="@android:color/holo_green_dark" />
</LinearLayout>
- header_listview.xml
(to make the ListView
header):
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#555555" >
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:text="@string/friend"
android:textColor="@android:color/white" />
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerInParent="true"
android:layout_marginLeft="5dp"
android:layout_toRightOf="@+id/text"
android:background="@drawable/blue_button"
android:contentDescription="@string/action_settings"
android:text="@string/goto_selected_list"
android:textColor="@android:color/white"
android:textSize="14sp" />
</RelativeLayout>
Running program, we have result like these srceens (click each image for full screen):