java - EditText需要改变颜色监听器

Question

嘿，这是我的代码，我需要一些帮助，当用户输入他的用户 ID 时，编辑文本需要从红色变为绿色，代码可以正常工作，但只有当您输入您的用户 ID，然后按 Enter 键时，我才需要它自动改变颜色。

editText1_id.Setontextchanged(new View.OnClickListener() {

        @Override
        public void onClick(View view) {

            if (editText1_id.getText().toString().isEmpty()) {
                Toast.makeText(getApplicationContext()," Please insert your User ID", Toast.LENGTH_SHORT).show();
            }else if ((editText1_id.length() < 4)){
                makeToastLogin("Please insert your User ID");
            } else {
                userId = editText1_id.getText().toString();
            }
            if (editText1_id.getText().toString().isEmpty()) {
                editText1_id.setBackgroundResource(R.drawable.buttonshap_red_outline);
            }else if (editText1_id.length() < 4){
                editText1_id.setBackgroundResource(R.drawable.buttonshap_red_outline);
            }else if (editText1_id.length() == 4) {
                editText1_id.setBackgroundResource(R.drawable.insert_frame);
            } else {
                editText1_id.setBackgroundResource(R.drawable.insert_frame);
            }

        }

    });

Answer 1

您可以将代码放入 TextWatcher 中，如下所示:

editText1_id.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

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

        }

        @Override
        public void afterTextChanged(Editable s) {
            if (editText1_id.getText().toString().isEmpty()) {
                editText1_id.setBackgroundResource(R.drawable.buttonshap_red_outline);
            }else if (editText1_id.length() < 4){
                editText1_id.setBackgroundResource(R.drawable.buttonshap_red_outline);
            }else if (editText1_id.length() == 4) {
                editText1_id.setBackgroundResource(R.drawable.insert_frame);
            } else {
                editText1_id.setBackgroundResource(R.drawable.insert_frame);
            }
        }
    });

如您所见，您可以将 addTextChangedListener 添加到每个 EditText。它有三个监听器，可以帮助您注意到用户何时开始输入