Android EditText 监听软键盘删除键 Binary

目标：如题

解决方法：

　　　　mEditTextTelNum.setOnKeyListener(new OnKeyListener() {

            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (keyCode == KeyEvent.KEYCODE_DEL) {
                    String content = mEditTextTelNum.getText().toString();
                    int length = content.length();
                    content.endsWith("-");
                }
                return false;
            }
        });