记 Android 部分布局忽然无法显示

总结：这是一个一开始方向错误的问题

某次，APK在测试手机上正常使用，故换了个荣耀X20的设备，想着兼容性应该没有问题，

结果，忽然发现A页面，一个底部布局无法显示，其它页面这个布局可以显示(使用的include)，

以为出现了什么奇葩的bug

查找许久，修改测试调整

后发现，原来是A页面初始化时，添加了一个隐藏软键盘的代码，如下

import android.app.Activity;
import android.content.Context;
import android.graphics.Rect;
import android.view.View;
import android.view.ViewTreeObserver;
import android.view.inputmethod.InputMethodManager;
import java.util.LinkedList;
import java.util.List;

public class SoftKeyboardStateHelper implements ViewTreeObserver.OnGlobalLayoutListener {

    public interface SoftKeyboardStateListener {
        void onSoftKeyboardOpened(int keyboardHeightInPx);
        void onSoftKeyboardClosed();
    }

    private final List<SoftKeyboardStateListener> listeners = new LinkedList<SoftKeyboardStateListener>();
    private final View activityRootView;
    private int        lastSoftKeyboardHeightInPx;
    private boolean    isSoftKeyboardOpened;

    public SoftKeyboardStateHelper(View activityRootView) {
        this(activityRootView, false);
    }

    public SoftKeyboardStateHelper(View activityRootView, boolean isSoftKeyboardOpened) {
        this.activityRootView     = activityRootView;
        this.isSoftKeyboardOpened = isSoftKeyboardOpened;
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(this);
    }

    @Override
    public void onGlobalLayout() {
        final Rect r = new Rect();
        //r will be populated with the coordinates of your view that area still visible.
        activityRootView.getWindowVisibleDisplayFrame(r);

        final int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
        if (!isSoftKeyboardOpened && heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
            isSoftKeyboardOpened = true;
            notifyOnSoftKeyboardOpened(heightDiff);
        } else if (isSoftKeyboardOpened && heightDiff < 100) {
            isSoftKeyboardOpened = false;
            notifyOnSoftKeyboardClosed();
        }
    }

    public void setIsSoftKeyboardOpened(boolean isSoftKeyboardOpened) {
        this.isSoftKeyboardOpened = isSoftKeyboardOpened;
    }

    public boolean isSoftKeyboardOpened() {
        return isSoftKeyboardOpened;
    }

    /**
     * Default value is zero (0)
     * @return last saved keyboard height in px
     */
    public int getLastSoftKeyboardHeightInPx() {
        return lastSoftKeyboardHeightInPx;
    }

    public void addSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.add(listener);
    }

    public void removeSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.remove(listener);
    }

    private void notifyOnSoftKeyboardOpened(int keyboardHeightInPx) {
        this.lastSoftKeyboardHeightInPx = keyboardHeightInPx;

        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardOpened(keyboardHeightInPx);
            }
        }
    }

    private void notifyOnSoftKeyboardClosed() {
        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardClosed();
            }
        }
    }

    /**
     * 判断软键盘是否弹出
     */
    public static boolean isSHowKeyboard(Context context, View v) {
        InputMethodManager imm = (InputMethodManager) context.getSystemService(context.INPUT_METHOD_SERVICE);
        if (imm.hideSoftInputFromWindow(v.getWindowToken(), 0)) {
            imm.showSoftInput(v, 0);
            return true;
            //软键盘已弹出
        } else {
            return false;
            //软键盘未弹出
        }
    }

}

    public static void setBottomBySoftKeyBoard(Activity activity, int root, View bottom) {
        final SoftKeyboardStateHelper softKeyboardStateHelper = new SoftKeyboardStateHelper(activity.findViewById(root));
        softKeyboardStateHelper.addSoftKeyboardStateListener(new SoftKeyboardStateHelper.SoftKeyboardStateListener() {
            @Override
            public void onSoftKeyboardOpened(int keyboardHeightInPx) {
                bottom.setVisibility(View.GONE);
            }

            @Override
            public void onSoftKeyboardClosed() {
                bottom.setVisibility(View.VISIBLE);
            }
        });
    }
}

后来发现这种写法，部分版本手机，如果没有开启软键盘的情况下，会将底部布局隐藏　　

后来修改为如下写法，此方法为标准写法，理论上应该兼容大部分手机

((InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(activity.getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);

　　

但是后来，低版本的手机没有什么问题，部分高版本手机，会直接闪退

再后来，添加了判断，如果有软键盘，再隐藏，

        if (SoftKeyboardStateHelper.isSHowKeyboard(activity, v)) {
            ((InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(activity.getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
        }

　　

最后修复了这个奇葩的问题