沉浸式webview输入框被输入法遮挡了怎么办？！

还是那个倒霉的双十一需求，测试时发现发弹幕的输入框被系统输入法挡住了，这个问题在之前UC内核的浏览器时没问题啊。经过各种对比定位，发现是因为这次需求还有个沉浸式的实现，就是这个实现导致输入框无法被弹起。所幸看到了AndroidBug5497Workaround (用我这个就够了)这篇blog，试验后效果拔群，唯独有个小遗憾是没有适配非沉浸式的状态，沉浸式和非沉浸式切换时会有个小黑条。小子不才遂在大神肩膀上狗尾续貂，以资来者。

原理

网传这是个Android固有的bug，具体原理我也没搞明白了，秉着又不是不能用的原则，先把问题解决了。

这个实现主要就是在键盘出现和消失的时候计算键盘、状态栏以及导航栏的高度，以便确定页面太高的大小。我的小调整就是增加一个沉浸式状态的传递，如果是沉浸式则需要少减一个状态栏的高度，仅此而已。

实现

Java代码

java 复制代码

public class AndroidBug5497Workaround {
	// For more information, see https://issuetracker.google.com/issues/36911528
	// To use this class, simply invoke assistActivity() on an Activity that already has its
	// content view set.

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

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

	private boolean isImmersive;

	private AndroidBug5497Workaround(Activity activity, boolean isImmersive) {
		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();
		this.isImmersive = isImmersive;
	}

	private int frameLayoutHeight = 0;

	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
				frameLayoutHeight = frameLayoutParams.height;// ！！！修改前保存原有高度
				// 是否沉浸式，增减状态栏高度
				int statusBarHeight = isImmersive && BarUtil.isSupportFitsSystem() ?
						BarUtils.getStatusBarHeight() : 0;
				frameLayoutParams.height = usableHeightSansKeyboard - heightDifference + statusBarHeight;
			} else {
				// keyboard probably just became hidden
				if (0 != frameLayoutHeight) {
					frameLayoutParams.height = frameLayoutHeight;// ！！！收起键盘恢复原有高度
				}
			}
			mChildOfContent.requestLayout();
			usableHeightPrevious = usableHeightNow;
		}
	}

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

在初始化webview的onCreate()方法中增加一句即可

AndroidBug5497Workaround.assistActivity(this, isImmersive);

参考

AndroidBug5497Workaround (用我这个就够了)