public class MainActivity extends AppCompatActivity {

    private WebView webView;

    private String path = "https://www.baidu.com/";
    private OrientationEventListener listener;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listener = new OrientationEventListener(this) {
            @Override
            public void onOrientationChanged(int orientation) {
                Log.i("lala","onOrientationChanged===>" + orientation);
                boolean isPortrait = PolyvScreenUtils.isPortrait(MainActivity.this);
                if ((orientation > -1 && orientation <= 10) || orientation >= 350 || (orientation <= 190 && orientation >= 170)) {
                    if (isPortrait){
                        PolyvScreenUtils.setLandscape(MainActivity.this);
                    }
                } else if ((orientation <= 100 && orientation >= 80) || (orientation <= 280 && orientation >= 260)) {
                    if (!isPortrait){
                        PolyvScreenUtils.setPortrait(MainActivity.this);
                    }
                }
            }
        };
        listener.enable();
        webView = findViewById(R.id.webView_guide);
        webView.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                super.onPageStarted(view, url, favicon);
            }

            @Override
            public void onPageFinished(WebView view, String url) {
                super.onPageFinished(view, url);
            }

        });
        webView.getSettings().setLoadWithOverviewMode(true);
        webView.getSettings().setUseWideViewPort(true);
        webView.loadUrl(path);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (listener != null){
            listener.disable();
        }
        if (webView != null) {
            webView.stopLoading();
            webView.loadDataWithBaseURL(null, "", "text/html", "utf-8", null);
            webView.clearHistory();
            ((ViewGroup) webView.getParent()).removeView(webView);
            webView.destroy();
            webView = null;
        }
    }

}

import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.res.Configuration;
import android.graphics.Point;
import android.os.Build;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.WindowManager;

/**
 * 与屏幕相关的工具类
 */
public class PolyvScreenUtils {
    private static int height16_9;

    // 生成竖屏下w:h=16:9的高
    public static int generateHeight16_9(Activity activity) {
        return height16_9 != 0 ? height16_9 : (height16_9 = getNormalWH(activity)[isPortrait(activity) ? 0 : 1] * 9 / 16);
    }

    // 获取竖屏下w:h=16:9的高
    public static int getHeight16_9() {
        return height16_9;
    }


    // 是否竖屏
    public static boolean isPortrait(Context context) {
        return context.getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT;
    }

    // 是否横屏
    public static boolean isLandscape(Context context) {
        return context.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE;
    }

    // 设置竖屏
    public static void setPortrait(Activity activity) {
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT);
    }

    // 设置横屏
    public static void setLandscape(Activity activity) {
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_LANDSCAPE);
    }

    /**
     * 获取包含状态栏的屏幕宽度和高度
     *
     * @param activity
     * @return {宽,高}
     */
    public static int[] getNormalWH(Activity activity) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
            DisplayMetrics dm = new DisplayMetrics();
            activity.getWindowManager().getDefaultDisplay().getMetrics(dm);
            return new int[]{dm.widthPixels, dm.heightPixels};
        } else {
            Point point = new Point();
            WindowManager wm = activity.getWindowManager();
            wm.getDefaultDisplay().getSize(point);
            return new int[]{point.x, point.y};
        }
    }

    // 重置状态栏
    public static void reSetStatusBar(Activity activity) {
        if (isLandscape(activity)) {
            hideStatusBar(activity);
            hideNavigationBar(activity);
        } else {
            setDecorVisible(activity);
        }
    }

    // 隐藏状态栏
    public static void hideStatusBar(Activity activity) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
            activity.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                    WindowManager.LayoutParams.FLAG_FULLSCREEN);
        } else {
            View decorView = activity.getWindow().getDecorView();
            activity.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                    WindowManager.LayoutParams.FLAG_FULLSCREEN);
            int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_IMMERSIVE | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
            decorView.setSystemUiVisibility(uiOptions);
        }
    }

    // 恢复为不全屏状态
    public static void setDecorVisible(Activity activity) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
            activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
        } else {
            View decorView = activity.getWindow().getDecorView();
            activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
            int uiOptions = View.SYSTEM_UI_FLAG_VISIBLE;
            decorView.setSystemUiVisibility(uiOptions);
        }
    }

    public static void hideNavigationBar(Activity activity) {
        int uiOptions = activity.getWindow().getDecorView().getSystemUiVisibility();
        activity.getWindow().getDecorView().setSystemUiVisibility(uiOptions | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
    }

    public static int dip2px(Context context, float dpValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (dpValue * scale + 0.5f);
    }

    public static int px2dip(Context context, float dpValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (dpValue / scale + 0.5f);
    }
}