Android Studio实现简单的通讯录
网上找的一个单页面通讯录，修改之后将添加联系人和修改/删除联系人分为两个独立页面
MainActivity
package com.example.test;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.text.method.ScrollingMovementMethod;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
MyHelper myHelper;
private TextView tvShow;
private Button btnAdd;
private Button btnQuery;
private Button btnUpdate;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myHelper = new MyHelper(this);
init();
}
private void init(){
tvShow = (TextView)findViewById(R.id.tv_show);
btnAdd = (Button)findViewById(R.id.btn_add);
btnQuery = (Button)findViewById(R.id.btn_query);
btnUpdate = (Button)findViewById(R.id.btn_update);
btnAdd.setOnClickListener(this); //Button控件设置监听
btnQuery.setOnClickListener(this);
btnUpdate.setOnClickListener(this);
findViewById(R.id.traceroute_rootview).setOnClickListener(this);
tvShow.setMovementMethod(ScrollingMovementMethod.getInstance()); //设置文本滚动
}
public void onClick(View v){
SQLiteDatabase db;
switch (v.getId()){
case R.id.traceroute_rootview:
InputMethodManager imm=(InputMethodManager)
getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(v.getWindowToken(),0);
break;
case R.id.btn_add: //添加联系人
Intent intent=new Intent(MainActivity.this,nextActivity.class);
startActivity(intent);
break;
case R.id.btn_query: //查询联系人
db = myHelper.getReadableDatabase();
Cursor cursor = db.rawQuery("select name,phone from person",null);
if (cursor.getCount() == 0){
tvShow.setText("");
Toast.makeText(this,"当前无联系人",Toast.LENGTH_SHORT).show();
}else {
cursor.moveToFirst();
tvShow.setText("Name：" + cursor.getString(0) + " ; Tel：" + cursor.getString(1));
while (cursor.moveToNext()){
tvShow.append("\n" + "Name：" + cursor.getString(0) + " ; Tel：" + cursor.getString(1));
}
}
cursor.close();
db.close();
break;
case R.id.btn_update: //修改联系人
Intent intent1=new Intent(MainActivity.this,xiugaiActivity.class);
startActivity(intent1);
break;
}
}
}
nextActivity
package com.example.test;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.database.sqlite.SQLiteDatabase;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class nextActivity extends AppCompatActivity implements View.OnClickListener {
MyHelper myHelper;
private EditText etName;
private EditText etPhone;
private Button btnAdd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.next);
myHelper = new MyHelper(this);
init();
}
private void init(){
etName = (EditText)findViewById(R.id.et_name);
etPhone = (EditText)findViewById(R.id.et_phone);
btnAdd = (Button)findViewById(R.id.btn_add);
btnAdd.setOnClickListener(this); //Button控件设置监听
findViewById(R.id.traceroute_rootview).setOnClickListener(this);
}
public void onClick(View v){
String name;
String phone;
SQLiteDatabase db;
switch (v.getId()) {
case R.id.traceroute_rootview:
InputMethodManager imm = (InputMethodManager)
getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(v.getWindowToken(), 0);
break;
case R.id.btn_add: //添加联系人
name = etName.getText().toString().trim();
phone = etPhone.getText().toString().trim();
db = myHelper.getWritableDatabase();
if (name.equals("") || phone.equals("")) { //联系人信息不能为空
Toast.makeText(this, "联系人信息添加失败", Toast.LENGTH_SHORT).show();
} else {
db.execSQL("insert into person (name,phone) values(?,?)", new Object[]{name, phone});
Toast.makeText(this, "联系人信息添加成功", Toast.LENGTH_SHORT).show();
}
db.close();
Intent intent=new Intent(nextActivity.this,MainActivity.class);
startActivity(intent);
break;
}
}
}
xiugaiActivity
package com.example.test;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.os.Bundle;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.text.method.ScrollingMovementMethod;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class xiugaiActivity extends AppCompatActivity implements View.OnClickListener{
MyHelper myHelper;
private EditText etName;
private EditText etPhone;
private TextView tvShow;
private Button btnQuery;
private Button btnUpdate;
private Button btnDelete;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.xiugai);
myHelper = new MyHelper(this);
init();
}
private void init(){
etName = (EditText)findViewById(R.id.et_name);
etPhone = (EditText)findViewById(R.id.et_phone);
tvShow = (TextView)findViewById(R.id.tv_show);
btnQuery = (Button)findViewById(R.id.btn_query);
btnUpdate = (Button)findViewById(R.id.btn_update);
btnDelete = (Button)findViewById(R.id.btn_delete);
btnQuery.setOnClickListener(this);
btnUpdate.setOnClickListener(this);
btnDelete.setOnClickListener(this);
findViewById(R.id.traceroute_rootview).setOnClickListener(this);
tvShow.setMovementMethod(ScrollingMovementMethod.getInstance()); //设置文本滚动
}
public void onClick(View v){
String name;
String phone;
SQLiteDatabase db;
switch (v.getId()){
case R.id.traceroute_rootview:
InputMethodManager imm=(InputMethodManager)
getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(v.getWindowToken(),0);
break;
case R.id.btn_query: //查询联系人
db = myHelper.getReadableDatabase();
Cursor cursor = db.rawQuery("select name,phone from person",null);
if (cursor.getCount() == 0){
tvShow.setText("");
Toast.makeText(this,"当前无联系人",Toast.LENGTH_SHORT).show();
}else {
cursor.moveToFirst();
tvShow.setText("Name：" + cursor.getString(0) + " ; Tel：" + cursor.getString(1));
while (cursor.moveToNext()){
tvShow.append("\n" + "Name：" + cursor.getString(0) + " ; Tel：" + cursor.getString(1));
}
}
cursor.close();
db.close();
break;
case R.id.btn_update: //修改联系人
db = myHelper.getWritableDatabase();
name = etName.getText().toString().trim();
phone = etPhone.getText().toString().trim();
if (name.equals("") || phone.equals("")){ //联系人信息不能为空
Toast.makeText(this,"不存在该联系人",Toast.LENGTH_SHORT).show();
}
else {
db.execSQL("update person set name=?,phone=? where name=?", new Object[]{name, phone, name});
Toast.makeText(this,"联系人信息修改成功",Toast.LENGTH_SHORT).show();
}
db.close();
break;
case R.id.btn_delete: //删除联系人
db = myHelper.getWritableDatabase();
name = etName.getText().toString().trim();
phone = etPhone.getText().toString().trim();
if (name.equals("") || phone.equals("")){ //联系人信息不能为空
Toast.makeText(this,"不存在该联系人",Toast.LENGTH_SHORT).show();
}
else {
db.execSQL("delete from person where name=? and phone=?", new Object[]{name, phone});
Toast.makeText(this,"联系人信息删除成功",Toast.LENGTH_SHORT).show();
}
db.close();
break;
}
}
}
MyHelper
package com.example.test;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class MyHelper extends SQLiteOpenHelper{
public MyHelper(Context context){
super(context, "alan.db", null ,2);
}
@Override
public void onCreate(SQLiteDatabase db){
db.execSQL("create table person(id integer primary key autoincrement,name varchar(20),phone varchar(20) unique)");
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/traceroute_rootview"
android:background="@color/white"
android:clickable="true"
android:gravity="center_horizontal"
tools:context=".MainActivity">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="通 讯 录"
android:textSize="30dp"
android:textStyle="italic"
android:gravity="center"
android:textColor="@color/black">
</TextView>
<Button
android:id="@+id/btn_add"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:text=" 添加联系人"
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
<Button
android:id="@+id/btn_query"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:text="查看联系人"
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
<Button
android:id="@+id/btn_update"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:text=" 修改联系人"
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
<TextView
android:id="@+id/tv_show"
android:layout_width="match_parent"
android:layout_height="180dp"
android:scrollbars="vertical"
android:layout_below="@+id/lineFour"
android:layout_marginTop="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="18dp"
android:textColor="#c2c8ec"
android:textSize="24dp"/>
</LinearLayout>
next.xml
<?xml version="1.0" encoding="utf-8"?>
<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:id="@+id/traceroute_rootview"
android:background="@color/white"
android:clickable="true"
android:orientation="vertical"
android:gravity="center_horizontal"
tools:context=".nextActivity">
<LinearLayout
android:id="@+id/lineTwo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/lineOne"
android:layout_marginTop="20dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="姓 名 : "
android:textSize="18dp"
android:textStyle="bold"/>
<EditText
android:id="@+id/et_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="请输入姓名"
android:textSize="16dp"
android:maxLines="1"
android:singleLine="true"
android:maxLength="14"/>
</LinearLayout>
<LinearLayout
android:id="@+id/lineTree"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/lineTwo"
android:layout_marginTop="10dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="电 话 : "
android:textSize="18dp"
android:textStyle="bold"/>
<EditText
android:id="@+id/et_phone"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="请输入手机号码"
android:textSize="16dp"
android:maxLines="1"
android:singleLine="true"
android:maxLength="11"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/lineFour"
android:layout_below="@+id/lineTree"
android:layout_marginTop="30dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp"
android:orientation="horizontal">
<Button
android:id="@+id/btn_add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:layout_weight="1"
android:text=" 确 定 "
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
</LinearLayout>
</RelativeLayout>
xiugai.xml
<?xml version="1.0" encoding="utf-8"?>
<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:id="@+id/traceroute_rootview"
android:background="@color/white"
android:clickable="true"
android:orientation="vertical"
android:gravity="center_horizontal"
tools:context=".xiugaiActivity">
<LinearLayout
android:id="@+id/lineTwo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/lineOne"
android:layout_marginTop="20dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="姓 名 : "
android:textSize="18dp"
android:textStyle="bold"/>
<EditText
android:id="@+id/et_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint=" 请输入姓名"
android:textSize="16dp"
android:maxLines="1"
android:singleLine="true"
android:maxLength="14"/>
</LinearLayout>
<LinearLayout
android:id="@+id/lineTree"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/lineTwo"
android:layout_marginTop="10dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="电 话 : "
android:textSize="18dp"
android:textStyle="bold"/>
<EditText
android:id="@+id/et_phone"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint=" 请输入手机号码"
android:textSize="16dp"
android:maxLines="1"
android:singleLine="true"
android:maxLength="11"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/lineFour"
android:layout_below="@+id/lineTree"
android:layout_marginTop="30dp"
android:layout_marginLeft="18dp"
android:layout_marginRight="18dp"
android:orientation="horizontal">
<Button
android:id="@+id/btn_query"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:layout_weight="1"
android:layout_marginLeft="4dp"
android:text="查看联系人"
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
<Button
android:id="@+id/btn_update"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:layout_weight="1"
android:layout_marginLeft="4dp"
android:text=" 修 改 "
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
<Button
android:id="@+id/btn_delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/shape"
android:layout_weight="1"
android:layout_marginLeft="4dp"
android:text=" 删 除 "
android:textSize="16dp"
android:textColor="#c2c8ec"
android:textStyle="bold"/>
</LinearLayout>
<TextView
android:id="@+id/tv_show"
android:layout_width="match_parent"
android:layout_height="180dp"
android:scrollbars="vertical"
android:layout_below="@+id/lineFour"
android:layout_marginTop="20dp"
android:layout_marginLeft="20dp"
android:layout_marginRight="18dp"
android:textColor="#c2c8ec"
android:textSize="24dp"/>
</RelativeLayout>
Mainfest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.Test">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".nextActivity"></activity>
<activity android:name=".xiugaiActivity"></activity>
</application>
</manifest>
初学android，程序还存在许多bug，大家多提修改建议。
