Android H5弹出软键盘遮挡输入框问题AndroidBug

Android内嵌H5页面呼出软键盘经常会遮挡输入框，最简单的解决方案是在AndroidManifest文件中对activity设置：android:windowSoftInputMode的值adjustPan或者adjustResize即可，像这样：

<activity
    android:name=".MainActivity"
    android:windowSoftInputMode="adjustPan"  >
</activity>

如果这样解决不了，那么就需要利用AndroidBug5497Workaround的解决方案
1.将AndroidBug5497Workaround代码拷贝到项目中
2.在相应的Activity中的onCreate方法中添加一句AndroidBug5497Workaround.assistActivity(this)即可
AndroidBug5497Workaround类

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 View mChildOfContent;
    private int usableHeightPrevious;
    private FrameLayout.LayoutParams frameLayoutParams;

    private AndroidBug5497Workaround(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();
        if (usableHeightNow != usableHeightPrevious) {
            int usableHeightSansKeyboard = mChildOfContent.getRootView().getHeight();
            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 - getNavigationBarHeight(mChildOfContent.getContext());
            }
            mChildOfContent.requestLayout();
            usableHeightPrevious = usableHeightNow;
        }
    }

    private int computeUsableHeight() {
        Rect r = new Rect();
        mChildOfContent.getWindowVisibleDisplayFrame(r);
        return (r.bottom - r.top);
    }

    private int getNavigationBarHeight(Context context) {
        boolean hasMenuKey = ViewConfiguration.get(context).hasPermanentMenuKey();
        if (!hasMenuKey) {
            // This device has a navigation bar
            int resourceId = context.getResources().getIdentifier("navigation_bar_height", "dimen", "android");
            if (checkNavigationBarShow(mChildOfContent.getContext()) && resourceId > 0) {
                return context.getResources().getDimensionPixelSize(resourceId);
            } else {
                return 0;
            }
        }
        return 0;
    }

 private boolean checkNavigationBarShow(@NonNull Context context) {
        boolean show = false;
        if (context instanceof Activity) {
            Window window = ((Activity) context).getWindow();
            Display display = window.getWindowManager().getDefaultDisplay();
            Point point = new Point();
            display.getRealSize(point);

            View decorView = window.getDecorView();
            Configuration conf = context.getResources().getConfiguration();
            if (Configuration.ORIENTATION_LANDSCAPE == conf.orientation) {
                View contentView = decorView.findViewById(android.R.id.content);
                show = (point.x != contentView.getWidth());
            } else {
                Rect rect = new Rect();
                decorView.getWindowVisibleDisplayFrame(rect);
                show = (rect.bottom != point.y);
            }
        }

        return show;
    }

}