Activity相关→ActivityUtils

75 阅读 0 评论 50 点赞

我是靠谱客的博主大意抽屉，最近开发中收集的这篇文章主要介绍Activity相关→ActivityUtils，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述


	import android.app.Activity;
	import android.content.Intent;
	import android.content.pm.PackageManager;
	import android.content.pm.ResolveInfo;
	import android.os.Build;
	import android.os.Bundle;
	import android.util.ArrayMap;

	import java.lang.reflect.Field;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;

	/**
	* <pre>
	* author: Blankj
	* blog : http://blankj.com
	* time : 2016/9/23
	* desc : Activity相关工具类
	* </pre>
	*/
	public final class ActivityUtils {

	private ActivityUtils() {
	throw new UnsupportedOperationException("u can't instantiate me...");
	}

	/**
	* 判断是否存在Activity
	*
	* @param packageName 包名
	* @param className activity全路径类名
	* @return {@code true}: 是<br>{@code false}: 否
	*/
	public static boolean isActivityExists(StringpackageName,String className) {
	Intent intent = new Intent();
	intent.setClassName(packageName, className);
	return !(Utils.getContext().getPackageManager().resolveActivity(intent,0)== null \|\|
	intent.resolveActivity(Utils.getContext().getPackageManager())==null \|\|
	Utils.getContext().getPackageManager().queryIntentActivities(intent,0).size()==0);
	}

	/**
	* 打开Activity
	*
	* @param packageName 包名
	* @param className 全类名
	*/
	public static void launchActivity(StringpackageName,String className) {
	launchActivity(packageName, className, null);
	}

	/**
	* 打开Activity
	*
	* @param packageName 包名
	* @param className 全类名
	* @param bundle bundle
	*/
	public static void launchActivity(StringpackageName,String className, Bundle bundle) {
	Utils.getContext().startActivity(IntentUtils.getComponentIntent(packageName, className, bundle));
	}

	/**
	* 获取launcher activity
	*
	* @param packageName 包名
	* @return launcher activity
	*/
	public static String getLauncherActivity(StringpackageName) {
	Intent intent = new Intent(Intent.ACTION_MAIN,null);
	intent.addCategory(Intent.CATEGORY_LAUNCHER);
	intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
	PackageManager pm = Utils.getContext().getPackageManager();
	List<ResolveInfo> infos= pm.queryIntentActivities(intent,0);
	for (ResolveInfo info: infos) {
	if (info.activityInfo.packageName.equals(packageName)) {
	return info.activityInfo.name;
	}
	}
	return "no "+ packageName;
	}


	/**
	* 获取栈顶Activity
	*
	* @return 栈顶Activity
	*/
	public static Activity getTopActivity() {
	try {
	Class activityThreadClass=Class.forName("android.app.ActivityThread");
	Object activityThread = activityThreadClass.getMethod("currentActivityThread").invoke(null);
	Field activitiesField = activityThreadClass.getDeclaredField("mActivities");
	activitiesField.setAccessible(true);
	Map activities = null;
	if (Build.VERSION.SDK_INT<Build.VERSION_CODES.KITKAT) {
	activities = (HashMap) activitiesField.get(activityThread);
	} else {
	activities = (ArrayMap) activitiesField.get(activityThread);
	}
	for (Object activityRecord: activities.values()) {
	Class activityRecordClass= activityRecord.getClass();
	Field pausedField = activityRecordClass.getDeclaredField("paused");
	pausedField.setAccessible(true);
	if (!pausedField.getBoolean(activityRecord)) {
	Field activityField = activityRecordClass.getDeclaredField("activity");
	activityField.setAccessible(true);
	return (Activity) activityField.get(activityRecord);
	}
	}
	} catch (Exception e) {
	e.printStackTrace();
	}
	return null;
	}
	}