在 android 上同时编辑两个文本

Question

我正在为 android 创建一个单位转换器。它有两个编辑文本，我想在用户输入数字时更新一个，但我无法获取它。

我已经尝试了几种方法，但到目前为止我无法使它起作用。我是 android 的新手，我已经在 java 中制作了这个应用程序，但在这里我似乎无法理解。

到目前为止，我已经掌握了使用点击方法的方法，但我非常希望它能在用户在编辑文本中输入数字时显示转换结果

Answer 1

用 addTextChangedListener 这样做：

yourEditText.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

            //do your conversion
            yourSecondEditText.setText(text);

        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

        }
    });

Answer 2

您应该按照 Chadi 的建议添加一个 TextChangedListener，但我建议以不同的模式实施。看看下面TextWatcher

的实现

        EditText firstEdit = (EditText) findViewById(R.id.firstEdit);

        firstEdit.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                // TODO Auto-generated method stub
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                // TODO Auto-generated method stub
            }

            @Override
            public void afterTextChanged(Editable s) {
               //Do here your conversion
               secondEdit.setText(convertedText);
            }
        });

我建议您使用 afterTextChanged，因为正如官方文档所述，您可以确定文本实际上已经更改。

官方文档：

This method is called to notify you that, somewhere within s, the text has been changed. It is legitimate to make further changes to s from this callback, but be careful not to get yourself into an infinite loop, because any changes you make will cause this method to be called again recursively. (You are not told where the change took place because other afterTextChanged() methods may already have made other changes and invalidated the offsets. But if you need to know here, you can use setSpan(Object, int, int, int) in onTextChanged(CharSequence, int, int, int) to mark your place and then look up from here where the span ended up.

在 android 上同时编辑两个文本

Two simultanious edit texts on android

android

android-edittext