我和一些朋友用 Java 写了一个聊天程序，现在我们想用它制作一个 Android 应用程序。我今天从基本功能开始。当我尝试运行它时，它会崩溃“不幸的是，您的应用程序崩溃了”或类似的东西。
主.java
package com.Linkr.linkrandroid;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.ArrayList;
import static com.Linkr.linkrandroid.R.*;
public class Chat extends Activity {
String username;
Socket sock;
BufferedReader reader;
PrintWriter writer;
ArrayList<String> userList = new ArrayList();
//Boolean isConnected = false;
TextView chatTextArea = (TextView) findViewById(R.id.chatTextArea);
TextView inputTextArea = (TextView) findViewById(id.inputTextArea);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(layout.activity_chat);
this.setTitle("Linkr");
}
public class IncomingReader implements Runnable{
public void run() {
String[] data;
String stream, done = "Done", connect = "Connect", disconnect = "Disconnect", chat = "Chat";
try {
while ((stream = reader.readLine()) != null) {
data = stream.split(":");
if (data[2].equals(chat)) {
chatTextArea.append(data[0] + ": " + data[1] + "\n");
//chatTextArea.setCaretPosition(chatTextArea.getDocument().getLength());
} else if (data[2].equals(connect)){
//chatTextArea.removeAll();
//userAdd(data[0]);
} else if (data[2].equals(disconnect)) {
//userRemove(data[0]);
} else if (data[2].equals(done)) {
/*usersList.setText("");
writeUsers();
userList.clear();
*/
}
}
}catch(Exception ex) {
}
}
}
public void ListenThread() {
Thread IncomingReader = new Thread(new IncomingReader());
IncomingReader.start();
}
public void userAdd(String data) {
userList.add(data);
}
public void userRemove(String data) {
chatTextArea.append(data + " has disconnected.\n");
}
public void writeUsers() {
String[] tempList = new String[(userList.size())];
userList.toArray(tempList);
/*for (String token:tempList) {
usersList.append(token + "\n");
}
*/
}
public void sendDisconnect() {
String bye = (username + ": :Disconnect");
try{
writer.println(bye); // Sends server the disconnect signal.
writer.flush(); // flushes the buffer
} catch (Exception e) {
chatTextArea.append("Could not send Disconnect message.\n");
}
}
public void Disconnect() {
try {
chatTextArea.append("Disconnected.\n");
sock.close();
} catch(Exception ex) {
chatTextArea.append("Failed to disconnect. \n");
}
isConnected = false;
//usersList.setText("");
}
private void onClickButton(View view) {
String nothing = "";
if ((inputTextArea.getText()).equals(nothing)) {
inputTextArea.setText("");
inputTextArea.requestFocus();
} else {
try {
writer.println(username + ":" + inputTextArea.getText() + ":" + "Chat");
writer.flush(); // flushes the buffer
} catch (Exception ex) {
chatTextArea.append("Message was not sent. \n");
}
inputTextArea.setText("");
inputTextArea.requestFocus();
}
inputTextArea.setText("");
inputTextArea.requestFocus();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.chat, menu);
return true;
}
}
acitivity_chat.xml
<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:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context=".Chat">
android:text = "Linkr"
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/inputTextArea"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="@+id/onClickButton"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Send"
android:id="@+id/onClickButton"
android:layout_below="@+id/chatTextArea"
android:layout_alignRight="@+id/chatTextArea"/>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textMultiLine"
android:ems="10"
android:id="@+id/chatTextArea"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_above="@+id/inputTextArea"
android:layout_alignParentRight="true"/>
感谢你们对我的帮助！<3