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

也有解决方案与系统嵌入,但它只适用于API >= 21 (Android L)。说你有BottomNavigationView,这是线性布局的孩子,你需要隐藏它时,键盘显示:

> LinearLayout
  > ContentView
  > BottomNavigationView

你所需要做的就是以这样的方式扩展LinearLayout:

public class KeyboardAwareLinearLayout extends LinearLayout {
    public KeyboardAwareLinearLayout(Context context) {
        super(context);
    }

    public KeyboardAwareLinearLayout(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public KeyboardAwareLinearLayout(Context context,
                                     @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public KeyboardAwareLinearLayout(Context context, AttributeSet attrs,
                                     int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    @Override
    public WindowInsets onApplyWindowInsets(WindowInsets insets) {
        int childCount = getChildCount();
        for (int index = 0; index < childCount; index++) {
            View view = getChildAt(index);
            if (view instanceof BottomNavigationView) {
                int bottom = insets.getSystemWindowInsetBottom();
                if (bottom >= ViewUtils.dpToPx(200)) {
                    // keyboard is shown
                    view.setVisibility(GONE);
                } else {
                    // keyboard is hidden
                    view.setVisibility(VISIBLE);
                }
            }
        }
        return insets;
    }
}

这个想法是,当键盘显示时,系统insets被改变为相当大的.bottom值。

其他回答

我花了一点时间才想明白……我运行它一些castexception,但发现你可以用类的名称替换layout.xml中的LinearLayout。

是这样的:

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent"
    xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/llMaster">

<com.ourshoppingnote.RelativeLayoutThatDetectsSoftKeyboard android:background="@drawable/metal_background"
    android:layout_width="fill_parent" android:layout_height="fill_parent"
    android:id="@+id/rlMaster" >
    <LinearLayout android:layout_width="fill_parent"
        android:layout_height="1dip" android:background="@drawable/line"></LinearLayout>

          ....

</com.ourshoppingnote.RelativeLayoutThatDetectsSoftKeyboard>    


</LinearLayout>

这样你就不会遇到任何演员问题。

... 如果你不想在每个页面上都这样做,我建议你使用“安卓版MasterPage”。点击这里查看链接: http://jnastase.alner.net/archive/2011/01/08/ldquomaster-pagesrdquo-in-android.aspx

我发现@Reuben_Scratton的方法与@Yogesh的方法的组合似乎效果最好。将他们的方法结合起来会产生如下结果:

final View activityRootView = findViewById(R.id.activityRoot);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
  @Override
  public void onGlobalLayout() {
    if (getResources().getConfiguration().keyboardHidden == Configuration.KEYBOARDHIDDEN_NO) { // Check if keyboard is not hidden
       // ... do something here
    }
  }
});

试试这个:

final View activityRootView = getWindow().getDecorView().getRootView();
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(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);

        int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
        if (heightDiff < activityRootView.getRootView().getHeight() / 4 ) { // if more than 100 pixels, its probably a keyboard...
             // ... do something here ... \\
        }
    }
});

你可以使用InputMethodManager。isActive方法,如果键盘可见则返回true:

    InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.isActive();

你也可以看到键盘在一个特定的视图中是否处于活动状态:

    imm.isActive(View v);

有一个隐藏的方法可以帮助这个,inputmethodmanager。getinputmethodwindowvisibleheight。但我不知道为什么要藏起来。

import android.content.Context
import android.os.Handler
import android.view.inputmethod.InputMethodManager

class SoftKeyboardStateWatcher(private val ctx: Context) {
  companion object {
    private const val DELAY = 10L
  }

  private val handler = Handler()
  private var isSoftKeyboardOpened: Boolean = false

  private val height: Int
    get() {
      val imm = ctx.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
      val method = imm.javaClass.getMethod("getInputMethodWindowVisibleHeight")
      method.isAccessible = true
      return method.invoke(imm) as Int
    }

  private val task: Runnable by lazy {
    Runnable {
      start()
      if (!isSoftKeyboardOpened && height > 0) {
        isSoftKeyboardOpened = true
        notifyOnSoftKeyboardOpened(height)
      } else if (isSoftKeyboardOpened && height == 0) {
        isSoftKeyboardOpened = false
        notifyOnSoftKeyboardClosed()
      }
    }
  }

  var listener: SoftKeyboardStateListener? = null

  interface SoftKeyboardStateListener {
    fun onSoftKeyboardOpened(keyboardHeightInPx: Int)
    fun onSoftKeyboardClosed()
  }

  fun start() {
    handler.postDelayed(task, DELAY)
  }

  fun stop() {
    handler.postDelayed({
      if (!isSoftKeyboardOpened) handler.removeCallbacks(task)
    }, DELAY * 10)
  }

  private fun notifyOnSoftKeyboardOpened(keyboardHeightInPx: Int) {
    listener?.onSoftKeyboardOpened(keyboardHeightInPx)
  }

  private fun notifyOnSoftKeyboardClosed() {
    listener?.onSoftKeyboardClosed()
  }
}