我想根据是否显示虚拟键盘来改变布局。我已经搜索了API和各种博客,但似乎找不到任何有用的东西。

这可能吗?

谢谢!


当前回答

我有个方法来做这件事。虽然似乎没有一种方法来检测软键盘何时显示或隐藏,但实际上,您可以通过在正在侦听的EditText上设置OnFocusChangeListener来检测它何时即将显示或隐藏。

EditText et = (EditText) findViewById(R.id.et);
et.setOnFocusChangeListener(new View.OnFocusChangeListener()
    {
        @Override
        public void onFocusChange(View view, boolean hasFocus)
        {
            //hasFocus tells us whether soft keyboard is about to show
        }
    });

注意:要注意的一件事是,当EditText获得或失去焦点时,这个回调将立即触发。这实际上会在软键盘显示或隐藏之前触发。我发现在键盘显示或隐藏之后做一些事情的最好方法是使用Handler并延迟一些事情~ 400ms,如下所示:

EditText et = (EditText) findViewById(R.id.et);
et.setOnFocusChangeListener(new View.OnFocusChangeListener()
    {
        @Override
        public void onFocusChange(View view, boolean hasFocus)
        {
            new Handler().postDelayed(new Runnable()
                {
                    @Override
                    public void run()
                    {
                        //do work here
                    }
                }, 400);
        }
    });

其他回答

我是这样做的:

添加OnKeyboardVisibilityListener接口。

public interface OnKeyboardVisibilityListener {
    void onVisibilityChanged(boolean visible);
}

HomeActivity.java:

public class HomeActivity extends Activity implements OnKeyboardVisibilityListener {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sign_up);
    // Other stuff...
    setKeyboardVisibilityListener(this);
}

private void setKeyboardVisibilityListener(final OnKeyboardVisibilityListener onKeyboardVisibilityListener) {
    final View parentView = ((ViewGroup) findViewById(android.R.id.content)).getChildAt(0);
    parentView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        private boolean alreadyOpen;
        private final int defaultKeyboardHeightDP = 100;
        private final int EstimatedKeyboardDP = defaultKeyboardHeightDP + (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ? 48 : 0);
        private final Rect rect = new Rect();

        @Override
        public void onGlobalLayout() {
            int estimatedKeyboardHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP, parentView.getResources().getDisplayMetrics());
            parentView.getWindowVisibleDisplayFrame(rect);
            int heightDiff = parentView.getRootView().getHeight() - (rect.bottom - rect.top);
            boolean isShown = heightDiff >= estimatedKeyboardHeight;

            if (isShown == alreadyOpen) {
                Log.i("Keyboard state", "Ignoring global layout change...");
                return;
            }
            alreadyOpen = isShown;
            onKeyboardVisibilityListener.onVisibilityChanged(isShown);
        }
    });
}


@Override
public void onVisibilityChanged(boolean visible) {
    Toast.makeText(HomeActivity.this, visible ? "Keyboard is active" : "Keyboard is Inactive", Toast.LENGTH_SHORT).show();
  }
}

希望这对你有所帮助。

桑德,我相信你是想展示被软键盘挡住的视野。试试这个http://android-developers.blogspot.com/2009/04/updating-applications-for-on-screen.html。

隐藏|显示事件键盘可以通过简单的hack在OnGlobalLayoutListener监听:

 final View activityRootView = findViewById(R.id.top_root);
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            public void onGlobalLayout() {
                int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();

                if (heightDiff > 100) {
                    // keyboard is up
                } else {
                    // keyboard is down
                }
            }
        });

这里activityRootView是Activity的根视图。

以上@Filipkowicz的答案在Android API < 30的情况下很好。由于Android API 30,我们应该使用setWindowInsetsAnimationCallback。所以下面的答案结合了这两种方法,以工作API 21 - 30。

private fun isKeyboardVisible(insets: WindowInsets): Boolean {
    val insetsCompat = WindowInsetsCompat.toWindowInsetsCompat(insets)
    val systemWindow = insetsCompat.systemWindowInsets
    val rootStable = insetsCompat.stableInsets
    if (systemWindow.bottom > rootStable.bottom) {
        // This handles the adjustResize case on < API 30, since
        // systemWindow.bottom is probably going to be the IME
        return true
    }
    return false
}

@JvmStatic
@BindingAdapter("goneWhenKeyboardVisible")
fun View.goneWhenKeyboardVisible() {
    if (isRPlus()) {
        setWindowInsetsAnimationCallback(object :
            WindowInsetsAnimation.Callback(DISPATCH_MODE_STOP) {
            override fun onProgress(
                insets: WindowInsets,
                runningAnimations: MutableList<WindowInsetsAnimation>
            ): WindowInsets {
                return insets
            }

            override fun onStart(
                animation: WindowInsetsAnimation,
                bounds: WindowInsetsAnimation.Bounds
            ): WindowInsetsAnimation.Bounds {
                if (isVisible)
                    isVisible = !rootWindowInsets.isVisible(WindowInsets.Type.ime())
                return super.onStart(animation, bounds)
            }

            override fun onEnd(animation: WindowInsetsAnimation) {
                super.onEnd(animation)
                if (!isVisible)
                    isVisible = !rootWindowInsets.isVisible(WindowInsets.Type.ime())
            }
        })
    } else {
        setOnApplyWindowInsetsListener { _, insets ->
            isVisible = !isKeyboardVisible(insets)
            insets
        }
    }
}

你也可以检查第一个DecorView的子底部填充。当键盘显示时,它将被设置为非零值。

@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
    View view = getRootView();
    if (view != null && (view = ((ViewGroup) view).getChildAt(0)) != null) {
        setKeyboardVisible(view.getPaddingBottom() > 0);
    }
    super.onLayout(changed, left, top, right, bottom);
}