在做橫豎屏展示時，發現網上適配虛擬鍵程式碼沒有做橫屏狀態下適配，導致橫屏狀態下，底部虛擬鍵遮擋了佈局內容。

所以橫屏狀態下也需要適配華為虛擬鍵。只需要在content佈局改變時，同時記錄當前可用的檢視寬度，重新請求佈局即可。下面是程式碼：

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Rect;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;

import java.lang.reflect.Method;

public class NavigationBarUtil {


    private static NavigationBarUtil Instance;

    public static NavigationBarUtil getInstance() {
        if (Instance != null) {
            Instance = new NavigationBarUtil();
        }
        return Instance;
    }


    public void initActivity(View content) {
        mObserved = content;
        //給View新增全域性的佈局監聽器監聽檢視的變化
        mObserved.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            public void onGlobalLayout() {
                resetViewHeight();
            }
        });
        layoutParams = mObserved.getLayoutParams();
    }

    private View mObserved;//被監聽的檢視
    private int usableHeightView;//檢視變化前的可用高度
    private int usableWidthView;//檢視變化前的可用寬度
    private ViewGroup.LayoutParams layoutParams;

    private NavigationBarUtil() {
    }

    /**
     * 重置檢視的高度，使不被底部虛擬鍵遮擋
     */
    private void resetViewHeight() {
        int usableHeightViewNow = CalculateAvailableHeight();
        int usableWidthViewNow = CalculateAvailableWidth();
        //比較佈局變化前後的View的可用高度
        if (usableHeightViewNow != usableHeightView) {
            //如果兩次高度不一致
            //將當前的View的可用高度設定成View的實際高度
            layoutParams.height = usableHeightViewNow;
            mObserved.requestLayout();//請求重新佈局
            usableHeightView = usableHeightViewNow;
        }
        if (usableWidthViewNow != usableWidthView) {
            layoutParams.width = usableWidthViewNow;
            mObserved.requestLayout();//請求重新佈局
            usableWidthView = usableWidthViewNow;
        }
    }

    /**
     * 計算檢視的寬度
     * @return
     */
    private int CalculateAvailableWidth() {
        Rect r = new Rect();
        mObserved.getWindowVisibleDisplayFrame(r);
        return (r.right);
    }

    /**
     * 計算檢視的高度
     *
     * @return
     */
    private int CalculateAvailableHeight() {
        Rect r = new Rect();
        mObserved.getWindowVisibleDisplayFrame(r);
//        return (r.bottom - r.top);//如果不是沉浸狀態列，需要減去頂部高度
        return (r.bottom);//如果是沉浸狀態列
    }

    /**
     * 判斷底部是否有虛擬鍵
     *
     * @param context
     * @return
     */
    public boolean hasNavigationBar(Context context) {
        boolean hasNavigationBar = false;
        Resources rs = context.getResources();
        int id = rs.getIdentifier("config_showNavigationBar", "bool", "android");
        if (id > 0) {
            hasNavigationBar = rs.getBoolean(id);
        }
        try {
            Class systemPropertiesClass = Class.forName("android.os.SystemProperties");
            Method m = systemPropertiesClass.getMethod("get", String.class);
            String navBarOverride = (String) m.invoke(systemPropertiesClass, "qemu.hw.mainkeys");
            if ("1".equals(navBarOverride)) {
                hasNavigationBar = false;
            } else if ("0".equals(navBarOverride)) {
                hasNavigationBar = true;
            }
        } catch (Exception e) {

        }
        return hasNavigationBar;

    }

}
 

 呼叫方式：在抽取的Activity基類中setContentView()方法後呼叫

        //適配華為部分機型虛擬鍵
        if (NavigationBarUtil.getInstance().hasNavigationBar(this)) {
            NavigationBarUtil.getInstance().initActivity(findViewById(android.R.id.content));
        }