自定义edittext

public class CustomEditText extends AppCompatEditText {
    private TextView lengthTextView;

    public CustomEditText(Context context) {
        super(context);
        init(context);
    }

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

    private void init(Context context) {
        lengthTextView = new TextView(context);
        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) {
                lengthTextView.setText("Length: " + s.length());
            }

            @Override
            public void afterTextChanged(Editable s) {}
        });
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        super.onLayout(changed, l, t, r, b);
        // 假设将长度显示在EditText的右侧
        lengthTextView.layout(r - 100, t, r, b); // 假设长度文本宽度为100px
    }
}