我正在寻找一个将一个单位转换为另一个单位(比如货币)的应用程序。所以它由2个编辑文本组成。一种是用户输入值,另一种是包含结果。现在,在这里,我希望在第一个编辑文本中输入值时,转换后的值出现在第二个编辑文本中,而不是使用“转换”按钮将值放入第二个编辑文本中。我怎样才能做到这一点?谢谢
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1 回答
3
TextWatcher
为此使用 a 。将其设置EditText
在用户键入的位置:
myEditText1.addTextChangedListener(new TextWatcher() {
@Override
public void afterTextChanged(Editable s) {
String value = s.toString();
// Perform computations using this string
// For example: parse the value to an Integer and use this value
// Set the computed value to the other EditText
myEditText2.setText(computedValue);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(final CharSequence s, int start, int before, int count) {
}
});
编辑 1:
检查空字符串""
:
myEditText1.addTextChangedListener(new TextWatcher() {
@Override
public void afterTextChanged(Editable s) {
String value = s.toString();
if (value.equals("")) {
myEditText1.setText("0");
// You may not need this line, because "myEditText1.setText("0")" will
// trigger this method again and go to else block, where, if your code is set up
// correctly, myEditText2 will get the value 0. So, try without the next line
// and if it doesn't work, put it back.
myEditText2.setText("0");
} else {
// Perform computations using this string
// For example: parse the value to an Integer and use this value
// Set the computed value to the other EditText
myEditText2.setText(computedValue);
}
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(final CharSequence s, int start, int before, int count){
}
});
于 2013-07-25T10:10:29.367 回答