Android软件盘遮挡webview中的输入框的正解

问题说明：
在使用53客服内嵌页面时，点击输入框发现软键盘遮住了输入框，很影响体验

问题原因：
webview存在的bug，需要动态的计算webview的高度才可以。

记录原因：
网上也有类似的代码，但是只是解决了虚拟键盘遮挡的问题，如果遇到有虚拟导航栏的话，还是存在遮挡问题，这里总结的方法两种问题都已解决。

正解方法：
加入如下代码：

import android.app.Activity;
import android.graphics.Rect;
import android.view.View;
import android.view.ViewTreeObserver;
import android.widget.FrameLayout;

public class AndroidBug5497Workaround {

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

    public static void assistActivity (Activity activity) {
        new AndroidBug5497Workaround(activity);
    }

    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; //之前的方法
                frameLayoutParams.height = computeUsableHeight(); //计算可用高度，解决虚拟导航遮挡问题
            }
            mChildOfContent.requestLayout();
            usableHeightPrevious = usableHeightNow;
        }
    }

    private int computeUsableHeight() {
        Rect r = new Rect();
        mChildOfContent.getWindowVisibleDisplayFrame(r);
        return r.bottom;// 全屏模式下： return r.bottom，非全屏：return r.bottom-r.top
    }

使用

setContentView(R.layout.layout_web);
AndroidBug5497Workaround.assistActivity(this);

网上也有类似的方案，仅在此记录一下。

frameLayoutParams.height = computeUsableHeight(); //计算可用高度，解决虚拟导航遮挡问题