闪屏与引导页部分功能的实现

注意：该demo只能适应几张图片滑动。如果多了需要参考自定义viewgroup引导页实现

1.当滑动到最后一页时显示立即进入按钮，其实也是判断viewpager的事件。当滑动到最后一个时显示就行。其它时候都隐藏

   //实现自己的PagerAdapter方法
        MyPagerAdapter pagerAdapter = new MyPagerAdapter();
        vp.setAdapter(pagerAdapter);
        //对滑动进行监听
        vp.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                if (position == 2) {//判断当滑动到第三页时进行操作
                    btn_welcome.setVisibility(View.VISIBLE);//设置控件为可看见
                    btn_welcome.setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            startActivity(new Intent(WelcomeActivity.this, DrawerLayoutActivity.class));//窗体跳转
                            finish();//结束本窗体
                        }
                    });
                } else {
                    btn_welcome.setVisibility(View.GONE);//否则不可见
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
    }

    class MyPagerAdapter extends PagerAdapter {

        @Override
        public int getCount() {//返回页面的数量
            return imgs.length;
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return view == object;
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {//实例化页面
            ImageView imageView = new ImageView(WelcomeActivity.this);
            imageView.setScaleType(ImageView.ScaleType.FIT_XY);
            imageView.setImageResource(imgs[position]);
            container.addView(imageView);//添加页面
            return imageView;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((View) object);//移除页面
        }
    }
}
2.闪屏功能的实现

        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_welcome);
        handleWelcome();
    }
    /**
     * 处理欢迎页面
     */
    private void handleWelcome() {
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                //打开主页并关闭欢迎页面
                Intent intent = new Intent(SplashActivity.this, WelcomeActivity.class);
                startActivity(intent);
                SplashActivity.this.finish();
            }
        },1500);
    }
}