WindowManager windowManager = (WindowManager) 
      applicationContext.getSystemService(Context.WINDOW_SERVICE);
  WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();
  layoutParams.type = WindowManager.LayoutParams.TYPE_TOAST;
  windowManager.addView(view, layoutParams);

public class BaseApplication extends Application {

  @Override
  public void onCreate() {
    super.onCreate();
    
    registerActivityLifecycleCallbacks(new ActivityLifecycleCallbacks() {

      @Override
      public void onActivityStarted(Activity activity) {
       if(findViewById(R.id.floating_view_id) != null) return;
       View view = LayoutInflater.from(activity).inflate(R.layout.floating_view, null);
       view.setId(R.id.floating_view_id);
       if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
         view.setTransitionName(activity.getString(R.string.transitionName));
       }
       WindowManager.LayoutParams params = new WindowManager.LayoutParams();
       params.gravity = Gravity.TOP | Gravity.LEFT;
       activity.addContentView(mPopView, mLayoutParams);
}
      
//省略...

  Intent intent = new Intent(this, Main2Activity.class);
  View view = findViewById(R.id.floating_view_id);
  if ( view != null) {
    ActivityOptionsCompat options = ActivityOptionsCompat.makeSceneTransitionAnimation(
        this,view, getString(R.string.transitionName));
    ContextCompat.startActivity(this, intent, options.toBundle());
  }else{
    startActivity(intent);
  }

  /**
   * Set the view to show.
   * @see #getView
   */
  public void setView(View view) {
    mNextView = view;
  }

/**
 * 自定义 toast , 无限时长
 * 可设置显示位置 尺寸
 */

class AlwaysShowToast {


  private Toast toast;

  private Object mTN;
  private Method show;
  private Method hide;

  private int mWidth = WindowManager.LayoutParams.WRAP_CONTENT;
  private int mHeight = WindowManager.LayoutParams.WRAP_CONTENT;


  public FixedFloatToast(Context applicationContext) {
    toast = new Toast(applicationContext);
  }


  public void setView(View view, int width, int height) {
    mWidth = width;
    mHeight = height;
    setView(view);
  }


  public void setView(View view) {
    toast.setView(view);
    initTN();
  }


  public void setGravity(int gravity, int xOffset, int yOffset) {
    toast.setGravity(gravity, xOffset, yOffset);
  }


  public void show() {
    try {
      show.invoke(mTN);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }


  public void hide() {
    try {
      hide.invoke(mTN);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }


  /**
   * 利用反射设置 toast 参数
   */
  private void initTN() {
    try {
      Field tnField = toast.getClass().getDeclaredField("mTN");
      tnField.setAccessible(true);
      mTN = tnField.get(toast);
      show = mTN.getClass().getMethod("show");
      hide = mTN.getClass().getMethod("hide");

      Field tnParamsField = mTN.getClass().getDeclaredField("mParams");
      tnParamsField.setAccessible(true);
      WindowManager.LayoutParams params = (WindowManager.LayoutParams) tnParamsField.get(mTN);
      params.flags = WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
          | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
      params.width = mWidth;
      params.height = mHeight;
      Field tnNextViewField = mTN.getClass().getDeclaredField("mNextView");
      tnNextViewField.setAccessible(true);
      tnNextViewField.set(mTN, toast.getView());

    } catch (Exception e) {
      e.printStackTrace();
    }
  }


}

  FixedFloatWindow fixedFloatWindow = new FixedFloatWindow(getApplicationContext());
  fixedFloatWindow.setView(view);
  fixedFloatWindow.setGravity(Gravity.RIGHT | Gravity.TOP, 100, 150);
  fixedFloatWindow.show();
//  fixedFloatWindow.hide();

  @Override
  public void onActivityStarted(Activity activity) {
    mActivityNum++;
    if (isNeedShow(activity)) {
      show();
    }else{
      hide();
    }
  }

  @Override
  public void onActivityStopped(Activity activity) {
    mActivityNum--;
    if (mActivityNum == 0) {
      hide();
    }
  }