android 显示内容被底部导航栏遮挡

Posted 2022-10-17 滕玉坤

描述：

由于产品需求，要求含有EditText的界面全屏显示，最好的解决方式是使用androidBug5497Workaround.assistActivity(this)
的方式来解决，但是华为和魅族手机系统自带的有底部导航栏，会造成一些布局被遮挡。

编辑此区域

解决方案：在values-21的style.xml中添加android:windowDrawsSystemBarBackgrounds”并将值设置为false，方式如下

• 在style引用的主题里面加入android:windowDrawsSystemBarBackgrounds”并将值设置为false，会自动提醒点击alt+Enter会新建values-21的文件夹并生成styles.xml的文件。
• 也可以自己忽略的，直接新建values-21的文件夹然后新建一个styles.xml的文件，将主题里面的内容复制到styles.xml里面然后加上加入android:windowDrawsSystemBarBackgrounds”并将值设置为false即可解决。

例外：附上（网上找到的）

public class AndroidBug5497Workaround 

    // For more information, see https://code.google.com/p/android/issues/detail?id=5497
    // To use this class, simply invoke assistActivity() on an Activity that already has its content 

view set.

    public static void assistActivity (Activity activity) 
        new AndroidBug5497Workaround(activity);
    
    private Activity activity;
    private View mChildOfContent;
    private int usableHeightPrevious;
    private FrameLayout.LayoutParams frameLayoutParams;

    private AndroidBug5497Workaround(Activity activity) 
        this.activity = activity;
        FrameLayout content = (FrameLayout) activity.findViewById(android.R.id.content);
        mChildOfContent = content.getChildAt(0);
        mChildOfContent.getViewTreeObserver().addOnGlobalLayoutListener(new 

ViewTreeObserver.OnGlobalLayoutListener() 
            public void onGlobalLayout() 
                possiblyResizeChildOfContent();
            
        );
        frameLayoutParams = (FrameLayout.LayoutParams) mChildOfContent.getLayoutParams();
    

    private void possiblyResizeChildOfContent() 
        int usableHeightNow = computeUsableHeight();
        LogUtils.e("possiblyResizeChildOfContent","usableHeightNow:"+usableHeightNow);
        LogUtils.e("possiblyResizeChildOfContent","usableHeightPrevious:"+usableHeightPrevious);
        if (usableHeightNow != usableHeightPrevious) 
            int usableHeightSansKeyboard = mChildOfContent.getRootView().getHeight();

            //这个判断是为了解决19之前的版本不支持沉浸式状态栏导致布局显示不完全的问题
            if(Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT)
                Rect frame = new Rect();
                activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
                int statusBarHeight = frame.top;
                usableHeightSansKeyboard -= statusBarHeight;
            
            int heightDifference = usableHeightSansKeyboard - usableHeightNow;
            if (heightDifference > (usableHeightSansKeyboard/4)) 
                // keyboard probably just became visible
                frameLayoutParams.height = usableHeightSansKeyboard - heightDifference;
             else 
                // keyboard probably just became hidden
                frameLayoutParams.height = usableHeightSansKeyboard;
            
            mChildOfContent.requestLayout();
            usableHeightPrevious = usableHeightNow;
        
    

    private int computeUsableHeight() 
        Rect frame = new Rect();
        activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
        int statusBarHeight = frame.top;

        Rect r = new Rect();
        mChildOfContent.getWindowVisibleDisplayFrame(r);

        //这个判断是为了解决19之后的版本在弹出软键盘时，键盘和推上去的布局（adjustResize）之间有黑色区域

的问题
        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT)
            return (r.bottom - r.top)+statusBarHeight;
        

        return (r.bottom - r.top);