android 确定键盘安卓获取键盘高度

转载

langrisser 2023-06-29 12:35:10

文章标签 android 确定键盘 android android studio ide 软键盘 文章分类 Android 移动开发

一、获取软键盘高度之方式一

要说获取软键盘的高度，那么肯定离不开 getViewTreeObserver().addOnGlobalLayoutListener 的方式。
只是使用起来又分不同的做法，最简单的是拿到Activity的ContentView，设置
contentView.getViewTreeObserver() .addOnGlobalLayoutListener(onGlobalLayoutListener);
然后在监听内部再通过 decorView.getWindowVisibleDisplayFrame来获取显示的Rect，在通过 decorView.getBottom() - outRect.bottom的方式来获取高度。
完整示例如下：

public final class Keyboard1Utils {

    public static int sDecorViewInvisibleHeightPre;
    private static ViewTreeObserver.OnGlobalLayoutListener onGlobalLayoutListener;
    private static int mNavHeight;

    private Keyboard1Utils() {
    }

    private static int sDecorViewDelta = 0;

    private static int getDecorViewInvisibleHeight(final Activity activity) {
        final View decorView = activity.getWindow().getDecorView();
        if (decorView == null) return sDecorViewInvisibleHeightPre;
        final Rect outRect = new Rect();
        decorView.getWindowVisibleDisplayFrame(outRect);

        int delta = Math.abs(decorView.getBottom() - outRect.bottom);

        if (delta <= mNavHeight) {
            sDecorViewDelta = delta;
            return 0;
        }
        return delta - sDecorViewDelta;
    }

    public static void registerKeyboardHeightListener(final Activity activity, final KeyboardHeightListener listener) {
        final int flags = activity.getWindow().getAttributes().flags;

        if ((flags & WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS) != 0) {
            activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
        }

        final FrameLayout contentView = activity.findViewById(android.R.id.content);
        sDecorViewInvisibleHeightPre = getDecorViewInvisibleHeight(activity);

        onGlobalLayoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                int height = getDecorViewInvisibleHeight(activity);
                if (sDecorViewInvisibleHeightPre != height) {

                    listener.onKeyboardHeightChanged(height);

                    sDecorViewInvisibleHeightPre = height;
                }
            }
        };

        //获取到导航栏高度之后再添加布局监听
        getNavigationBarHeight(activity, new NavigationBarCallback() {
            @Override
            public void onHeight(int height, boolean hasNav) {
                mNavHeight = height;
                contentView.getViewTreeObserver().addOnGlobalLayoutListener(onGlobalLayoutListener);
            }
        });


    }

    public static void unregisterKeyboardHeightListener(Activity activity) {
        onGlobalLayoutListener = null;
        View contentView = activity.getWindow().getDecorView().findViewById(android.R.id.content);
        if (contentView == null) return;
        contentView.getViewTreeObserver().removeGlobalOnLayoutListener(onGlobalLayoutListener);
    }

    private static int getNavBarHeight() {
        Resources res = Resources.getSystem();
        int resourceId = res.getIdentifier("navigation_bar_height", "dimen", "android");
        if (resourceId != 0) {
            return res.getDimensionPixelSize(resourceId);
        } else {
            return 0;
        }
    }

    public static void getNavigationBarHeight(Activity activity, NavigationBarCallback callback) {

        View view = activity.getWindow().getDecorView();
        boolean attachedToWindow = view.isAttachedToWindow();

        if (attachedToWindow) {

            WindowInsetsCompat windowInsets = ViewCompat.getRootWindowInsets(view);
            assert windowInsets != null;

            int height = windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom;

            boolean hasNavigationBar = windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars()) &&
                    windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom > 0;

            if (height > 0) {
                callback.onHeight(height, hasNavigationBar);
            } else {
                callback.onHeight(getNavBarHeight(), hasNavigationBar);
            }

        } else {

            view.addOnAttachStateChangeListener(new View.OnAttachStateChangeListener() {
                @Override
                public void onViewAttachedToWindow(View v) {

                    WindowInsetsCompat windowInsets = ViewCompat.getRootWindowInsets(v);
                    assert windowInsets != null;
                    int height = windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom;

                    boolean hasNavigationBar = windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars()) &&
                            windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom > 0;

                    if (height > 0) {
                        callback.onHeight(height, hasNavigationBar);
                    } else {
                        callback.onHeight(getNavBarHeight(), hasNavigationBar);
                    }

                }

                @Override
                public void onViewDetachedFromWindow(View v) {
                }
            });
        }
    }

    public interface KeyboardHeightListener {
        void onKeyboardHeightChanged(int height);
    }
}

使用：

override fun init() {

        Keyboard1Utils.registerKeyboardHeightListener(this) {

            YYLogUtils.w("当前的软键盘高度：$it")
        
        }
}

需要注意的是方法内部获取导航栏的方法是过时的，部分手机会有问题，但是并没有用它做计算，只是用于一个Flag，终归还是能用，经过我的测试也并不会影响效果。

二、获取软键盘高度之方式二

获取软键盘高度的第二种方式也是使用 getViewTreeObserver().addOnGlobalLayoutListener 的方式，不过不同的是，它是在Activity添加了一个PopupWindow，然后让软键盘弹起的时候，计算PopopWindow移动了多少范围，从而计算软键盘的高度。

它创建一个看不见的弹窗，即宽为0，高为全屏，并为弹窗设置全局布局监听器。当布局有变化，比如有输入法弹窗出现或消失时，监听器回调函数就会被调用。而其中的关键就是当输入法弹出时，它会把之前我们创建的那个看不见的弹窗往上挤，这样我们创建的那个弹窗的位置就变化了，只要获取它底部高度的变化值就可以间接的获取输入法的高度了。
这里我对源码做了一点修改

public class KeyboardHeightUtils extends PopupWindow {

    private KeyboardHeightListener mListener;
    private View popupView;
    private View parentView;
    private Activity activity;

    public KeyboardHeightUtils(Activity activity) {
        super(activity);
        this.activity = activity;

        LayoutInflater inflator = (LayoutInflater) activity.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        this.popupView = inflator.inflate(R.layout.keyboard_popup_window, null, false);
        setContentView(popupView);

        setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE | WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
        setInputMethodMode(PopupWindow.INPUT_METHOD_NEEDED);

        parentView = activity.findViewById(android.R.id.content);

        setWidth(0);
        setHeight(WindowManager.LayoutParams.MATCH_PARENT);

        popupView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

            @Override
            public void onGlobalLayout() {
                if (popupView != null) {
                    handleOnGlobalLayout();
                }
            }
        });
    }

    public void start() {

        parentView.addOnAttachStateChangeListener(new View.OnAttachStateChangeListener() {
            @Override
            public void onViewAttachedToWindow(View view) {
                if (!isShowing() && parentView.getWindowToken() != null) {
                    setBackgroundDrawable(new ColorDrawable(0));
                    showAtLocation(parentView, Gravity.NO_GRAVITY, 0, 0);
                }
            }

            @Override
            public void onViewDetachedFromWindow(View view) {
            }
        });

    }

    public void close() {
        this.mListener = null;
        dismiss();
    }

    public void registerKeyboardHeightListener(KeyboardHeightListener listener) {
        this.mListener = listener;
    }

    private void handleOnGlobalLayout() {

        Point screenSize = new Point();
        activity.getWindowManager().getDefaultDisplay().getSize(screenSize);

        Rect rect = new Rect();
        popupView.getWindowVisibleDisplayFrame(rect);

        int keyboardHeight = screenSize.y - rect.bottom;

        notifyKeyboardHeightChanged(keyboardHeight);
    }


    private void notifyKeyboardHeightChanged(int height) {
        if (mListener != null) {
            mListener.onKeyboardHeightChanged(height);
        }
    }

    public interface KeyboardHeightListener {
        void onKeyboardHeightChanged(int height);
    }

}

使用的方式：

override fun init() {

        keyboardHeightUtils = KeyboardHeightUtils(this)
        keyboardHeightUtils.registerKeyboardHeightListener {
            YYLogUtils.w("第二种方式：当前的软键盘高度：$it")
        }
        keyboardHeightUtils.start()

    }
    
    override fun onDestroy() {
        super.onDestroy()
        Keyboard1Utils.unregisterKeyboardHeightListener(this)

        keyboardHeightUtils.close();
    }

和第一种方案有异曲同工之妙，都是一个方法，但是思路有所不同，但是这种方法也有一个坑点，就是需要计算状态栏的高度。可以看到第二种方案和第一种方案有一个状态栏高度的偏差，大家记得处理即可。

三、获取软键盘高度之方式三

如果能直接使用兼容方案，那肯定是完美的:

ViewCompat.setWindowInsetsAnimationCallback(window.decorView, object : WindowInsetsAnimationCompat.Callback(DISPATCH_MODE_STOP) {
         override fun onProgress(insets: WindowInsetsCompat, runningAnimations: MutableList<WindowInsetsAnimationCompat>): WindowInsetsCompat {

                val isVisible = insets.isVisible(WindowInsetsCompat.Type.ime())
                val keyboardHeight = insets.getInsets(WindowInsetsCompat.Type.ime()).bottom

                //当前是否展示
                YYLogUtils.w("isVisible = $isVisible")
                //当前的高度进度回调
                YYLogUtils.w("keyboardHeight = $keyboardHeight")

                return insets
            }
        })

        ViewCompat.getWindowInsetsController(findViewById(android.R.id.content))?.apply {

            show(WindowInsetsCompat.Type.ime())

        }

可惜想法很好，实际上也只有在Android R 以上才好用，低版本要么就只触发一次，要么就干脆不触发。兼容性的方案也有兼容性问题！

我们需要在Android11上使用动画监听的方案，而Android11一下使用 setOnApplyWindowInsetsListener 的方式来获取。

代码大概如下

fun addKeyBordHeightChangeCallBack(view: View, onAction: (height: Int) -> Unit) {
        var posBottom: Int
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
            val cb = object : WindowInsetsAnimation.Callback(DISPATCH_MODE_STOP) {
                override fun onProgress(
                    insets: WindowInsets,
                    animations: MutableList<WindowInsetsAnimation>
                ): WindowInsets {
                    posBottom = insets.getInsets(WindowInsets.Type.ime()).bottom +
                            insets.getInsets(WindowInsets.Type.systemBars()).bottom
                    onAction.invoke(posBottom)
                    return insets
                }
            }
            view.setWindowInsetsAnimationCallback(cb)
        } else {
            ViewCompat.setOnApplyWindowInsetsListener(view) { _, insets ->
                posBottom = insets.getInsets(WindowInsetsCompat.Type.ime()).bottom +
                        insets.getInsets(WindowInsetsCompat.Type.systemBars()).bottom
                onAction.invoke(posBottom)
                insets
            }
        }
    }

但是实测之后发现，就算是兼容版本的 setOnApplyWindowInsetsListener 方法，获取状态栏和导航栏没有问题，但是当软键盘弹起和收起的时候并不会再次回调，也就是部分设备和版本只能调用一次，再次弹软键盘的时候就不触发了。

如果觉得不保险大家也可以在控件上屏之后再设置监听，onResume中设置监听，这样确保是设置监听成功，在Android11以上的设备，使用兼容方案的监听是可以拿到监听，Android11以下的设备有些也可以拿到监听。

所以我们如果想兼容版本的话，那没办法了，只能出绝招了,我们就把 Android11 以下的机型使用 getViewTreeObserver().addOnGlobalLayoutListener 的方式，而 Android11 以上的我们使用 WindowInsets 的方案，这样就是最为保险的方式。
具体的兼容方案如下：

public final class Keyboard4Utils {

    public static int sDecorViewInvisibleHeightPre;
    private static ViewTreeObserver.OnGlobalLayoutListener onGlobalLayoutListener;
    private static int mNavHeight;

    private Keyboard4Utils() {
    }

    private static int sDecorViewDelta = 0;

    private static int getDecorViewInvisibleHeight(final Activity activity) {
        final View decorView = activity.getWindow().getDecorView();
        if (decorView == null) return sDecorViewInvisibleHeightPre;
        final Rect outRect = new Rect();
        decorView.getWindowVisibleDisplayFrame(outRect);

        int delta = Math.abs(decorView.getBottom() - outRect.bottom);
        if (delta <= mNavHeight) {
            sDecorViewDelta = delta;
            return 0;
        }
        return delta - sDecorViewDelta;
    }

    public static void registerKeyboardHeightListener(final Activity activity, final KeyboardHeightListener listener) {

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
            invokeAbove31(activity, listener);
        } else {
            invokeBelow31(activity, listener);
        }


    }

    @RequiresApi(api = Build.VERSION_CODES.R)
    private static void invokeAbove31(Activity activity, KeyboardHeightListener listener) {

        activity.getWindow().getDecorView().setWindowInsetsAnimationCallback(new WindowInsetsAnimation.Callback(DISPATCH_MODE_STOP) {
            @NonNull
            @Override
            public WindowInsets onProgress(@NonNull WindowInsets windowInsets, @NonNull List<WindowInsetsAnimation> list) {

                int imeHeight = windowInsets.getInsets(WindowInsetsCompat.Type.ime()).bottom;
                int navHeight = windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom;
                boolean hasNavigationBar = windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars()) &&
                        windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom > 0;

                listener.onKeyboardHeightChanged(hasNavigationBar ? Math.max(imeHeight - navHeight, 0) : imeHeight);

                return windowInsets;
            }
        });
    }

    private static void invokeBelow31(Activity activity, KeyboardHeightListener listener) {

        final int flags = activity.getWindow().getAttributes().flags;

        if ((flags & WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS) != 0) {
            activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
        }

        final FrameLayout contentView = activity.findViewById(android.R.id.content);
        sDecorViewInvisibleHeightPre = getDecorViewInvisibleHeight(activity);

        onGlobalLayoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                int height = getDecorViewInvisibleHeight(activity);
                if (sDecorViewInvisibleHeightPre != height) {

                    listener.onKeyboardHeightChanged(height);

                    sDecorViewInvisibleHeightPre = height;
                }
            }
        };

        //获取到导航栏高度之后再添加布局监听
        getNavigationBarHeight(activity, new NavigationBarCallback() {
            @Override
            public void onHeight(int height, boolean hasNav) {
                mNavHeight = height;
                contentView.getViewTreeObserver().addOnGlobalLayoutListener(onGlobalLayoutListener);
            }
        });

    }

    public static void unregisterKeyboardHeightListener(Activity activity) {
        onGlobalLayoutListener = null;
        View contentView = activity.getWindow().getDecorView().findViewById(android.R.id.content);
        if (contentView == null) return;
        contentView.getViewTreeObserver().removeGlobalOnLayoutListener(onGlobalLayoutListener);
    }

    private static int getNavBarHeight() {
        Resources res = Resources.getSystem();
        int resourceId = res.getIdentifier("navigation_bar_height", "dimen", "android");
        if (resourceId != 0) {
            return res.getDimensionPixelSize(resourceId);
        } else {
            return 0;
        }
    }

    public static void getNavigationBarHeight(Activity activity, NavigationBarCallback callback) {

        View view = activity.getWindow().getDecorView();
        boolean attachedToWindow = view.isAttachedToWindow();

        if (attachedToWindow) {

            WindowInsetsCompat windowInsets = ViewCompat.getRootWindowInsets(view);
            assert windowInsets != null;

            int height = windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom;

            boolean hasNavigationBar = windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars()) &&
                    windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom > 0;

            if (height > 0) {
                callback.onHeight(height, hasNavigationBar);
            } else {
                callback.onHeight(getNavBarHeight(), hasNavigationBar);
            }

        } else {

            view.addOnAttachStateChangeListener(new View.OnAttachStateChangeListener() {
                @Override
                public void onViewAttachedToWindow(View v) {

                    WindowInsetsCompat windowInsets = ViewCompat.getRootWindowInsets(v);
                    assert windowInsets != null;
                    int height = windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom;

                    boolean hasNavigationBar = windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars()) &&
                            windowInsets.getInsets(WindowInsetsCompat.Type.navigationBars()).bottom > 0;

                    if (height > 0) {
                        callback.onHeight(height, hasNavigationBar);
                    } else {
                        callback.onHeight(getNavBarHeight(), hasNavigationBar);
                    }

                }

                @Override
                public void onViewDetachedFromWindow(View v) {
                }
            });
        }
    }

    public interface KeyboardHeightListener {
        void onKeyboardHeightChanged(int height);
    }
}

本文章为转载内容，我们尊重原作者对文章享有的著作权。如有内容错误或侵权问题，欢迎原作者联系我们进行内容更正或删除文章。