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

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()
  }
}

其他回答

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)
    }
}

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);

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
    }
  }
});

这是我的解决方案,它很有效。而不是寻找像素大小,只是检查内容视图的高度是否改变:

// Scroll to the latest comment whenever the keyboard is shown
commentsContent.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        private int oldHeight;

        @Override
        public void onGlobalLayout() {
            int newHeight = commentsContent.getMeasuredHeight();
            if (newHeight < oldHeight) {
                // Check for the keyboard showing in case the height difference
                // is a result of orientation change
                if (isSoftKeyboardShowing(CommentsActivity.this)) {
                    // Keyboard is showing so scroll to the latest comment
                    scrollToLatestComment();
                }
            }
            oldHeight = newHeight;
        }

    });


public static boolean isSoftKeyboardShowing(Activity activity) {
    InputMethodManager inputMethodManager = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
    return inputMethodManager.isActive();
}

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()
  }
}