如何在BACK按下后用软键盘关闭活动？

Question

我有一个Activity,我希望软件键盘可以打开.如何在BACK键盘打开后关闭活动？现在我必须单击BACK两次,首先关闭键盘,然后完成Activity.

Answer 1

如上所述,onKeyPreIme可用于捕获后退按钮,但这需要在文本视图上覆盖,而不是在活动中.

这是一个完整的解决方案:

首先,从EditText派生的新类重写onKeyPreIme并调用回调接口:

// EditTextWithBackButton class
public class EditTextWithBackButton extends EditText
{
    public interface IOnBackButtonListener
    {
        boolean OnEditTextBackButton();
    }

    public EditTextWithBackButton(Context context)
    {
        super(context);
    }

    public EditTextWithBackButton(Context context, AttributeSet attrs)
    {
        super(context, attrs);
    }

    public void setOnBackButtonListener(IOnBackButtonListener l)
    {
        _listener = l;
    }

    IOnBackButtonListener _listener;

    @Override
    public boolean onKeyPreIme(int keyCode, KeyEvent event)
    {
        if (event.getAction()==KeyEvent.ACTION_UP && keyCode==KeyEvent.KEYCODE_BACK)
        {
            if (_listener!=null && _listener.OnEditTextBackButton())
                return false;
        }
        return super.onKeyPreIme(keyCode, event);    //To change body of overridden methods use File | Settings | File Templates.
    }
}

接下来,更新您的布局:

<com.yournamespace.whatever.EditTextWithBackButton
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/textField"
        />

接下来,在setContentView之后,在OnCreate中更新您的活动:

((EditTextWithBackButton) findViewById(R.id.textField)).setOnBackButtonListener(new EditTextWithBackButton.IOnBackButtonListener()
{
    @Override
    public boolean OnEditTextBackButton()
    {
        finish();
        return true;
    }
});

Answer 2

您可以使用以下内容

  @Override
public boolean onKeyUp(int keyCode, KeyEvent event) 
    {
    if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
           finish();
           return true;
    }
    return super.onKeyUp(keyCode, event);
}