我需要做一件非常简单的事情-找出软件键盘是否显示。这在Android中可行吗?


当前回答

抱歉回答晚了,但我已经创建了一个小的帮助类来处理打开/关闭事件,通知侦听器和其他有用的东西,可能有人会发现它有帮助:

import android.graphics.Rect;
import android.view.View;
import android.view.ViewTreeObserver;

import java.util.LinkedList;
import java.util.List;

public class SoftKeyboardStateWatcher 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 SoftKeyboardStateWatcher(View activityRootView) {
        this(activityRootView, false);
    }

    public SoftKeyboardStateWatcher(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 {@code 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();
            }
        }
    }
}

使用的例子:

final SoftKeyboardStateWatcher softKeyboardStateWatcher 
    = new SoftKeyboardStateWatcher(findViewById(R.id.activity_main_layout);

// Add listener
softKeyboardStateWatcher.addSoftKeyboardStateListener(...);
// then just handle callbacks

其他回答

不要编写任何硬代码。最好的方法是,你必须调整你的视图,而Get Focus on EditText与键盘显示。 您可以使用下面的代码将活动上的resize属性添加到清单文件中。

android: windowSoftInputMode = adjustResize”

参考@TacB0sS的回答,我在Kotlin中开发了一个类。希望这对你有所帮助。如果需要改进,请告诉我。

class KeyboardVisibilityObserver(val layRootContainer: View?, val keyboardVisibilityListener: KeyboardVisibilityListener?) {
    var isKeyboardOpen = false
        private set

    private var keyBoardObserver = object : ViewTreeObserver.OnGlobalLayoutListener {

        private val DefaultKeyboardDP = 100

        // Lollipop includes button bar in the root. Add height of button bar (48dp) to maxDiff
        private val EstimatedKeyboardDP = DefaultKeyboardDP + if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) 48 else 0

        private val r = Rect()

        override fun onGlobalLayout() {
            if (layRootContainer != null) {
                // Convert the dp to pixels.
                val estimatedKeyboardHeight = TypedValue
                        .applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP.toFloat(), layRootContainer.resources.displayMetrics).toInt()

                // Conclude whether the keyboard is shown or not.
                layRootContainer.getWindowVisibleDisplayFrame(r)
                val heightDiff = layRootContainer.rootView.height - (r.bottom - r.top)
                val isShown = heightDiff >= estimatedKeyboardHeight

                if (isShown == isKeyboardOpen) {
                    //  Log.d("Keyboard state", "Ignoring global layout change...");
                    return
                }

                isKeyboardOpen = isShown

                keyboardVisibilityListener?.onKeyboardVisibilityChanged(isKeyboardOpen)
            }
        }
    }

    init {
        layRootContainer?.viewTreeObserver?.addOnGlobalLayoutListener(keyBoardObserver)
    }

    // call this in onDestroy
    fun removeObserver(){
        layRootContainer?.viewTreeObserver?.removeOnGlobalLayoutListener(keyBoardObserver)
    }

    interface KeyboardVisibilityListener {
        fun onKeyboardVisibilityChanged(isKeyboardOpen: Boolean)
    }
}

除了正确的答案,我必须在onCreateView的末尾添加这个,当使用一个片段内的webview。

getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);

可能是因为我在一个片段中运行Webview,或者可能是API 30上的一个新行为,我的问题是,即使显示键盘,片段的高度也从未改变。

所以对于Fragment,整个代码应该是

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = super.onCreateView(inflater, container, savedInstanceState);
    //mWebView.postUrl("https://www.google.com/");
    final View activityRootView = view;
    layoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {
            Rect r = new Rect();
            //r will be populated with the coordinates of your view that area still visible.
            activityRootView.getWindowVisibleDisplayFrame(r);
            // This variable was created only for Debug purposes and 
            // to see the height change when clicking on a field inside mWebView
            int screenHeight = activityRootView.getRootView().getHeight();
            Log.d("onGlobalLayout", "rect: " + r.toString());
            Log.d("onGlobalLayout", "screenHeight: " + screenHeight);

            //The difference on the heights from bottom to top and on the root height
            int heightDiff = screenHeight - (r.bottom - r.top);
            Log.d("onGlobalLayout", "heightDiff: " + heightDiff);

            //I suggest to put 250 on resources to have better order
            float dpx = dpToPx(getActivity(), 250);

            if (previousHeightDiff != heightDiff) {
                if (heightDiff > dpx) {
                    isSoftKeyboardPresent = true;
                } else {
                    isSoftKeyboardPresent = false;
                }
                previousHeightDiff = heightDiff;
            }
        }
    };
    activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(layoutListener);
    getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);
    return view;
}

private static float dpToPx(Context context, float valueInDp) {
    DisplayMetrics metrics = context.getResources().getDisplayMetrics();
    return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, valueInDp, metrics);
}

有一种直接的方法可以找出答案。而且,它不需要任何布局更改。 所以,它也可以在沉浸式全屏模式下工作。 诀窍在于,您尝试隐藏或显示软键盘,并捕获尝试的结果。 没有恐慌,这并不真正显示或隐藏键盘。我们只要求状态。 为了保持最新,您可以简单地重复操作,例如,每200毫秒,使用处理器。 您可以在这里找到一个实现:https://stackoverflow.com/a/27567074/2525452

就计算机而言,这是永远的问题,但这个问题仍然令人难以置信地相关!

所以我把上面的答案结合起来,做了一些改进……

public interface OnKeyboardVisibilityListener {


    void onVisibilityChanged(boolean visible);
}

public final void setKeyboardListener(final OnKeyboardVisibilityListener listener) {
    final View activityRootView = ((ViewGroup) getActivity().findViewById(android.R.id.content)).getChildAt(0);

    activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

        private boolean wasOpened;

        private final int DefaultKeyboardDP = 100;

        // From @nathanielwolf answer...  Lollipop includes button bar in the root. Add height of button bar (48dp) to maxDiff
        private final int EstimatedKeyboardDP = DefaultKeyboardDP + (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ? 48 : 0);

        private final Rect r = new Rect();

        @Override
        public void onGlobalLayout() {
            // Convert the dp to pixels.
            int estimatedKeyboardHeight = (int) TypedValue
                    .applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP, activityRootView.getResources().getDisplayMetrics());

            // Conclude whether the keyboard is shown or not.
            activityRootView.getWindowVisibleDisplayFrame(r);
            int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
            boolean isShown = heightDiff >= estimatedKeyboardHeight;

            if (isShown == wasOpened) {
                Log.d("Keyboard state", "Ignoring global layout change...");
                return;
            }

            wasOpened = isShown;
            listener.onVisibilityChanged(isShown);
        }
    });
}

对我有用:)

注意: 如果你注意到DefaultKeyboardDP不适合你的设备播放的值,并发表评论,让每个人都知道应该是什么值…最终我们将得到适合所有设备的正确值!

要了解更多细节,请查看Cyborg上的实现