Android, реализующий чат-пузырь в ListView
Я нахожусь в процессе написания чата на Android, но у меня возникли проблемы с добавлением чата в мой клиент. Мой экран чата состоит изListView
с текстовым полем и кнопкой «Отправить» внизу. Для исходящего сообщения тексты выравниваются вListView
ряд. Для входящего сообщения тексты выровнены по правому краю вListView
ряд. Тем не менее, размер чата не изменяется в зависимости от длины текстов входящих сообщений. Эта проблема не возникает для выровненного по левому краю исходящего сообщения.
Здесь снимок экрана ниже.
Изображение http://i40.tinypic.com/5fgen6.png
Тексты сообщений чата хранятся в базе данных и отображаются вListView
через адаптер курсора. Выравнивание текстов чата определяется на лету в исходном коде Java вMessageAdapter
, Оба чата пузыри сделаны с использованием девяти патч изображения Android.
Ниже мой макет активности чата,ListView
с проблемойmessageHistoryList
:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:padding="10dip"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="@+id/messageHistoryList"
android:layout_width="wrap_content"
android:layout_height="0px"
android:layout_weight="1"/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<EditText
android:id="@+id/message"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="top"
android:layout_weight="1"/>
<Button
android:id="@+id/sendMessageButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="4"
android:text="Send"/>
</LinearLayout>
</LinearLayout>
Расположение строк ListView:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/userAndMessage">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textUser"
android:textStyle="bold"
android:textColor="@color/blue"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textMessage"
android:textColor="@color/blue"
android:textStyle="bold"/>
</RelativeLayout>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textTime"
android:textColor="@color/blue"/>
</RelativeLayout>
Адаптер сообщений:
public class MessageAdapter extends SimpleCursorAdapter {
static final String[] FROM = { ChatHistoryManager.C_TIME };
static final int[] TO = { R.id.textTime };
static final int MESSAGE_INCOMING_DIR = 1;
private String incomingMessageUserName;
private String selfUserName;
public MessageAdapter(Context context, Cursor cursor) {
super(context, R.layout.message_list_item, cursor, FROM, TO);
}
@Override
public void bindView(View row, Context context, Cursor cursor) {
super.bindView(row, context, cursor);
int messageDir = cursor.getInt(cursor.getColumnIndex(ChatHistoryManager.C_DIR));
if(messageDir == MESSAGE_INCOMING_DIR) {
RelativeLayout.LayoutParams userNameAndChatMessageParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
userNameAndChatMessageParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE);
RelativeLayout.LayoutParams userNameParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
userNameParams.addRule(RelativeLayout.LEFT_OF, R.id.textMessage);
RelativeLayout.LayoutParams chatMessageParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
chatMessageParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, R.id.textUser);
RelativeLayout.LayoutParams timeParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
timeParams.addRule(RelativeLayout.ALIGN_RIGHT, R.id.userAndMessage);
timeParams.addRule(RelativeLayout.BELOW, R.id.userAndMessage);
row.setBackgroundResource(R.color.grey);
// Set the chat message
String chatMessage = cursor.getString(cursor.getColumnIndex(ChatHistoryManager.C_TEXT));
TextView textMessage = (TextView) row.findViewById(R.id.textMessage);
textMessage.setText(chatMessage.trim());
textMessage.setLayoutParams(chatMessageParams);
// Format the time stamp of the message
long timestamp = cursor.getLong(cursor.getColumnIndex(ChatHistoryManager.C_TIME));
TextView textTime = (TextView) row.findViewById(R.id.textTime);
String readableTimeStamp = (String) DateUtils.getRelativeTimeSpanString(timestamp);
textTime.setText(readableTimeStamp.trim());
textTime.setLayoutParams(timeParams);
// Format the message owner and the message
TextView textUser = (TextView) row.findViewById(R.id.textUser);
textUser.setText(incomingMessageUserName + ": ");
textUser.setLayoutParams(userNameParams);
row.setBackgroundResource(R.drawable.incoming_chat_bubble);
}
else {
RelativeLayout.LayoutParams userNameAndChatMessageParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
userNameAndChatMessageParams.addRule(RelativeLayout.RIGHT_OF, R.id.userImage);
RelativeLayout.LayoutParams userImageParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
userImageParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
RelativeLayout.LayoutParams userNameParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
userNameParams.addRule(RelativeLayout.ALIGN_LEFT, R.id.userAndMessage);
RelativeLayout.LayoutParams chatMessageParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
chatMessageParams.addRule(RelativeLayout.RIGHT_OF, R.id.textUser);
RelativeLayout.LayoutParams timeParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
timeParams.addRule(RelativeLayout.ALIGN_LEFT, R.id.userAndMessage);
timeParams.addRule(RelativeLayout.BELOW, R.id.userAndMessage);
// Set the chat message
String chatMessage = cursor.getString(cursor.getColumnIndex(ChatHistoryManager.C_TEXT));
TextView textMessage = (TextView) row.findV,iewById(R.id.textMessage);
textMessage.setText(chatMessage);
textMessage.setLayoutParams(chatMessageParams);
// Format the time stamp of the message
long timestamp = cursor.getLong(cursor.getColumnIndex(ChatHistoryManager.C_TIME));
TextView textTime = (TextView) row.findViewById(R.id.textTime);
textTime.setText(DateUtils.getRelativeTimeSpanString(timestamp));
textTime.setLayoutParams(timeParams);
// Format the message owner and the message
TextView textUser = (TextView) row.findViewById(R.id.textUser);
textUser.setText(selfUserName + ": ");
textUser.setLayoutParams(userNameParams);
row.setBackgroundResource(R.drawable.outgoing_chat_bubble);
}
}
public void setIncomingMessageUserName(String inputUserName) {
this.incomingMessageUserName = inputUserName;
}
public void setSelfUserName(String inputUserName) {
this.selfUserName = inputUserName;
}
}