Android基础-向导页搭建 (防卡顿,和防OOM,适配高低内存手机兼容)

以下代码支持Ctrl+C  Ctrl+V 超快速集成办法

xml 文件 :

   

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/colorAccent"
    >

    <android.support.v4.view.ViewPager
        android:id="@+id/guid_viewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </android.support.v4.view.ViewPager>

    <Button
        android:visibility="invisible"
        android:id="@+id/buton_begin"
        android:textColor="@color/colorPrimary"
        android:layout_marginBottom="50dp"
        android:layout_centerHorizontal="true"
        android:layout_alignParentBottom="true"
        android:layout_width="wrap_content"
        android:layout_height="30dp"
        android:background="@drawable/bg_txt_circle_solide_f5f5f5"
        android:textSize="14sp"
        android:text="点击开始"/>

    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="30dp">

        <LinearLayout
            android:orientation="horizontal"
            android:id="@+id/guid_indicator_container"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content">
        </LinearLayout>
        <!--红色的点-->
        <ImageView
            android:id="@+id/guid_indicator_selected"
            android:layout_width="10dp"
            android:layout_height="10dp"
            android:src="@mipmap/dot_focus"/>
    </RelativeLayout>

</RelativeLayout>

acitivity.java 代码逻辑

public class GuideActivity extends AppCompatActivity implements View.OnClickListener {

    private RelativeLayout                    mActivity_main;
    private android.support.v4.view.ViewPager mGuidViewPager;
    private Button                            mButonBegin;
    private LinearLayout                      mGuidIndicatorContainer;
    private ImageView                         mGuidIndicatorSelected;
    private int[]                             mGuidArray;
    private ImageView                         mMImageView;//滑动的动态大图片

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_guide);
        init();
    }

    protected void init() {
        initView();
        initData();
        initEvent();
    }

    //初始化视图
    protected void initView() {
        mActivity_main = (RelativeLayout) findViewById(R.id.activity_main);
        mGuidViewPager = (android.support.v4.view.ViewPager) findViewById(R.id.guid_viewPager);
        mButonBegin = (Button) findViewById(R.id.buton_begin);
        mGuidIndicatorContainer = (LinearLayout) findViewById(R.id.guid_indicator_container);
        mGuidIndicatorSelected = (ImageView) findViewById(R.id.guid_indicator_selected);
    }

    //初始化数据
    private void initData() {
        //实现viewpager和数据的绑定
        //创建数据集
        mGuidArray = new int[]{R.drawable.bg_guide1, R.drawable.bg_guide1, R.drawable.bg_guide1};
        //设置适配器
        mGuidViewPager.setAdapter(new GuidPagerAdapter());

        //动态的添加indicator
        for (int i = 0; i < mGuidArray.length; i++) {
            ImageView ivIndicator = new ImageView(GuideActivity.this);
            ivIndicator.setImageResource(R.mipmap.dot_normal);

            //给数字赋单位
            int unit = (int) (TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, getResources().getDisplayMetrics()) + .5f);
            int width = unit;//10dp
            int height = unit;//10dp

            LinearLayout.LayoutParams parmas = new LinearLayout.LayoutParams(width, height);

            if (i == 0) {//第一个点
                mGuidIndicatorContainer.addView(ivIndicator, parmas);
            } else {
                //左间距
                parmas.leftMargin = unit * 5;//设置两点之间的距离.
                mGuidIndicatorContainer.addView(ivIndicator, parmas);
            }
        }

    }

    //初始化事件
    protected void initEvent() {
        mButonBegin.setOnClickListener(this);
        initListener();
    }

    class GuidPagerAdapter extends PagerAdapter {

        @Override
        public int getCount() {
            if (mGuidArray != null) {
                return mGuidArray.length;
            }
            return 0;
        }

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            //view
            ImageView imageView = new ImageView(GuideActivity.this);
            imageView.setScaleType(ImageView.ScaleType.FIT_XY);
            //data
            int resId = mGuidArray[position];
            try {
                getBitmapForImgResourse(GuideActivity.this, resId, imageView);
            } catch (Exception e) {
                Glide.with(GuideActivity.this).load(resId).placeholder(resId).diskCacheStrategy(DiskCacheStrategy.RESULT).into(imageView);
            }

            //加入容器
            container.addView(imageView);

            return imageView;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((View) object);
        }
    }

    //滑动监听的方法
    private void initListener() {
        mGuidViewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {

            private int mSpace;

            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                //position 移动的页面的索引的位置
                //positionoffset 页面移动的比值---页面移动出去的宽度/页面总的宽度
                //positionOffsetPixels 页面移动出去的宽度
                //space 两个点之间的距离(从第一个点移动到第二个点需要的距离)
                if (mSpace == 0) {
                    mSpace = mGuidIndicatorContainer.getChildAt(1).getLeft() - mGuidIndicatorContainer.getChildAt(0).getLeft();
                }
                int marginLeft = (int) (mSpace * position + mSpace * positionOffset + .5f);
                //设置红色点的marginLeft
                RelativeLayout.LayoutParams curLayoutparms = (RelativeLayout.LayoutParams) mGuidIndicatorSelected.getLayoutParams();
                curLayoutparms.leftMargin = marginLeft;

                //重新设置LayoutParams
                mGuidIndicatorSelected.setLayoutParams(curLayoutparms);
            }

            @Override
            public void onPageSelected(int position) {
                if (position == mGuidViewPager.getAdapter().getCount() - 1) {
                    mButonBegin.setVisibility(View.VISIBLE);
                } else {
                    mButonBegin.setVisibility(View.INVISIBLE);
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
    }

    //点击开始按钮的点击事件

    public void onClick(View v) {
        //存储已经走完向导页的状态
        AppConfig.put(this, Constant.GUIDE, true);
        Constant.GUIDE_FLAG = true;
        Intent intent = new Intent(this, LoginActivity.class);
        startActivity(intent);
        finish();
    }

    @Override
    protected void onStop() {
        super.onStop();
    }

    /**
     * 大图片处理机制
     * 利用Bitmap 转存 R图片
     */
    public static Bitmap btp;

    public void getBitmapForImgResourse(Context mContext, int imgId, ImageView mImageView) {
        try {
            mMImageView = mImageView;
            InputStream is = mContext.getResources().openRawResource(imgId);
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = false;
            options.inPreferredConfig = Bitmap.Config.RGB_565;
            options.inPurgeable = true;
            options.inInputShareable = true;
            options.inSampleSize = 1;
            btp = BitmapFactory.decodeStream(is, null, options);
            if (btp != null && mImageView != null) {//防止使用的时候,该图片已经被回收了.
                mImageView.setImageBitmap(btp);
            }
            is.close();
        } catch (Exception e) {

        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (btp != null) {
            btp.recycle();
            btp = null;
        }
        if (mMImageView != null) {
            try {
                mMImageView.setBackground(null);
            } catch (Exception e) {

            }

        }

        System.gc();
    }
}

 以上代码经过本人各项目长时间几千万次运行和踩坑,如有不妥,使劲拍砖,  并指出问题点,和更好的改良办法.!!!.请不惜赐教!!!