Android开发App源码是指按照Java编写规则和Android应用程序开发的规范开发的Android移动应用程序的代码文件。Android平台的应用程序开发通常采用Java语言、Android SDK和Eclipse等开发工具。下面就以一个跑步记录App为例，介绍Android开发App源码。
1. 创建新项目
打开Android Studio，点击"Create New Project"按钮，输入项目名称和包名，选择最低支持Android版本和手机屏幕尺寸，选择Empty Activity模板，点击Next按钮。
2. 设置变量和布局文件
在MainActivity.java中，定义Activity布局文件所包含的TextView和ListView对象：
```java
TextView distanceTextView;
TextView timeTextView;
TextView speedTextView;
ListView timeList;
ArrayAdapter
ArrayList
```
3. 实现计时器功能
使用android.os.CountDownTimer类实现计时器的功能，定义以下成员变量：
```java
private CountDownTimer countDownTimer;
private String time = ""
private long timeSpent;
```
在onCreate()方法中初始化计时器、设置计时时间和计时完成后执行的操作：
```java
countDownTimer = new CountDownTimer(MAX_TIME_MILLIS, 1000) {
@Override
public void onTick(long millisUntilFinished) {
timeSpent += 1000;
time = DateUtils.formatElapsedTime(timeSpent / 1000);
timeTextView.setText(String.format("%s %s", getString(R.string.time_num), time));
}
@Override
public void onFinish() {
timeTextView.setVisibility(View.GONE);
}
};
```
4. 添加定位功能
使用Android的LocationManager，在AndroidManifest.xml添加定位的权限：
```xml
```
在MainActivity.java中定义以下成员变量：
```java
private static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private LocationManager locationManager;
private LocationListener locationListener;
private Location currentLocation;
```
在onCreate()方法中获取定位权限并注册Listener：
```java
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationListener = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
currentLocation = location;
distanceTextView.setText(String.format("%s %s", getString(R.string.distance_num), String.valueOf(distance)));
speedTextView.setText(String.format("%s %s", getString(R.string.speed_num), String.valueOf(speed)));
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSIONS_REQUEST_LOCATION);
} else {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
}
} else {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
}
```
5. 实现ListView
在onCreate()方法中实现ListView：
```java
arrayList = new ArrayList
adapter = new ArrayAdapter
timeList.setAdapter(adapter);
```
在LocationListener回调方法中，添加记录行走距离和更新速度的功能：
```java
if (currentLocation != null) {
float[] results = new float[1];
Location.distanceBetween(previousLocation.getLatitude(), previousLocation.getLongitude(),
currentLocation.getLatitude(), currentLocation.getLongitude(), results);
float distanceInMeters = results[0];
distance += distanceInMeters;
speed = currentLocation.getSpeed();
previousLocation = currentLocation;
arrayList.add(time + "\n" + String.format("%s %.2f km", getString(R.string.distance_num), distance / 1000) + "\n" + String.format("%s %.2f km/h", getString(R.string.speed_num), (speed * 3600) / 1000));
adapter.notifyDataSetChanged();
}
```
以上就是跑步记录App的源码分析和实现流程，其他类型的App也都有各自的特点和功能，开发者可以根据自己的需求进行开发并发布。
