Android软键盘的打开和关闭的监听

布局文件

Activity

public class InputDialogActivity extends BaseActivity {
    @BindView(R.id.etListener)
    EditText mEtListener;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_input_dialog);
        ButterKnife.bind(this);
        setListenerFotEditText(findViewById(R.id.activity_main_layout));
    }
    private void setListenerFotEditText(View view){
        SoftKeyboardStateHelper softKeyboardStateHelper = new SoftKeyboardStateHelper(view);
        softKeyboardStateHelper.addSoftKeyboardStateListener(new SoftKeyboardStateHelper.SoftKeyboardStateListener() {
            @Override
            public void onSoftKeyboardOpened(int keyboardHeightInPx) {
                //键盘打开
                Toast.makeText(InputDialogActivity.this, mEtListener.getText().toString() + "打开", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onSoftKeyboardClosed() {
                //键盘关闭
                Toast.makeText(InputDialogActivity.this, mEtListener.getText().toString() + "关闭", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

SoftKeyboardStateHelper

public class SoftKeyboardStateHelper implements ViewTreeObserver.OnGlobalLayoutListener {
    public interface SoftKeyboardStateListener {
        void onSoftKeyboardOpened(int keyboardHeightInPx);
        void onSoftKeyboardClosed();
    }

    private final List listeners = new LinkedList();
    private final View activityRootView;
    private int lastSoftKeyboardHeightInPx;
    private boolean isSoftKeyboardOpened;

    public SoftKeyboardStateHelper(View activityRootView) {
        this(activityRootView, false);
    }

    public SoftKeyboardStateHelper(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 addSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.add(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();
            }
        }
    }
}

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