Android 判断程序前后台状态

港控/mmm° 2022-05-20 02:59 207阅读 0赞

原文 :  [http://onewayonelife.iteye.com/blog/1157776][http_onewayonelife.iteye.com_blog_1157776]

package org.wp.activity;
    
    import java.util.List;
    
    import android.app.ActivityManager;
    import android.app.ActivityManager.RunningAppProcessInfo;
    import android.app.Service;
    import android.content.Context;
    import android.content.Intent;
    import android.os.IBinder;
    import android.util.Log;
    
    public class AppStatusService extends Service {
    	private static final String TAG = "AppStatusService";
    	private ActivityManager activityManager;
    	private String packageName;
    
    	@Override
    	public IBinder onBind(Intent intent) {
    		return null;
    	}
    
    	@Override
    	public int onStartCommand(Intent intent, int flags, int startId) {
    		activityManager = (ActivityManager) this.getSystemService(Context.ACTIVITY_SERVICE);
    		packageName = this.getPackageName();
    		new Thread() {
    			public void run() {
    				try {
    					while (true) {
    						Thread.sleep(1000);
    						if (isAppOnForeground()) {
    							Log.i(TAG, "true");
    						} else {
    							Log.i(TAG, "false");
    						}
    					}
    				} catch (Exception e) {
    					e.printStackTrace();
    				}
    			}
    		}.start();
    		return super.onStartCommand(intent, flags, startId);
    	}
    
    	private boolean isAppOnForeground() {
    		// Returns a list of application processes that are running on the device
    		List<RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
    		if (appProcesses == null) return false;
    		for (RunningAppProcessInfo appProcess : appProcesses) {
    			// importance:
    			// The relative importance level that the system places 
    			// on this process.
    			// May be one of IMPORTANCE_FOREGROUND, IMPORTANCE_VISIBLE, 
    			// IMPORTANCE_SERVICE, IMPORTANCE_BACKGROUND, or IMPORTANCE_EMPTY.
    			// These constants are numbered so that "more important" values are
    			// always smaller than "less important" values.
    			// processName:
    			// The name of the process that this object is associated with.
    			if (appProcess.processName.equals(packageName)
    					&& appProcess.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
    				return true;
    			}
    		}
    		return false;
    	}
    }

[http_onewayonelife.iteye.com_blog_1157776]: http://onewayonelife.iteye.com/blog/1157776