限制EditText输入字符及其事件监听

ゝ一纸荒年。 2022-08-19 13:24 202阅读 0赞

package org.sina.android;
    
    
    import android.app.Activity;
    import android.os.Bundle;
    import android.text.Editable;
    import android.text.TextWatcher;
    import android.util.Log;
    import android.widget.EditText;
    import android.widget.TextView;
    
     //限制EditText输入字符
    
    public class AndroidTestActivity extends Activity { 
    
        private EditText inputa;
        private EditText inputb;
        private TextView result;
    
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.auto_layout);
    
            inputa = (EditText) findViewById(R.id.inputa);
            inputb = (EditText) findViewById(R.id.inputb);
    
            result = (TextView) findViewById(R.id.result);
    
            inputa.addTextChangedListener(new TextFilter(inputa));
            inputb.addTextChangedListener(new TextFilter(inputb));
        }
    
        private boolean textFilter(String text) {
    
            boolean isLegal = false;
    //trim()为String类方法，去掉字符串两端空格
            if (null != text && !"".equals(text.trim())) {
                if (text.indexOf(".") > 0) {
                    if (text.endsWith(".")) {
                        isLegal = text.matches("^\\d{1,4}\\.$");
                    } else {
                        isLegal = text.matches("^\\d{1,4}\\.\\d$");
                    }
                } else {
                    isLegal = text.matches("^\\d{1,4}$");
                }
            }
            return isLegal;
        }
    
        class TextFilter implements TextWatcher {
    
            private EditText editText;
    
            private String rt;
    
            public TextFilter(EditText editText) {
                this.editText = editText;
            }
    
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {
                Log.w("beforeTextChanged", "-----------------------------------");
                Log.e("beforeTextChanged@ ", " CharSequence: " + s + " -start: "
                        + start + " -count: " + count);
            }
    
            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
    
                Log.w("onTextChanged", "-----------------------------------");
                Log.e("onTextChanged@ ", "CharSequence: " + s + " -start: " + start
                        + " before: " + before + " -count: " + count);
    
                String a = inputa.getText().toString();
                String b = inputb.getText().toString();
                if (null != s && !"".equals(s.toString().trim())) {
                    String input = s.toString();
                    if (textFilter(input)) {
                        if (isEmpty(a) || isEmpty(b)) {
                            result.setText("0.00");
                        } else {
                            double ad = Double.parseDouble(a);
                            double bd = Double.parseDouble(b);
                            result.setText(String.format("%1$.2f", (ad * bd)));
                        }
                    } else {
                        editText.setText(input.substring(0, start)
                                + input.substring(start + count));
                        editText.requestFocus();
                        editText.setSelection(start);
                    }
                }
                else
                {
                    checkResult(a, b);
                }
            }
    
            @Override
            public void afterTextChanged(Editable s) {
                // editText.setText(rt);
                Log.w("afterTextChanged", "-----------------------------------");
                Log.e("afterTextChanged@ ", s.toString());
            }
            private void checkResult(String a, String b)
            {
                if (!Utils.isEmpty(a) && !Utils.isEmpty(b))
                {
                    return;
                }
                String resultStr = trim(a) + trim(b);
                if (isEmpty(resultStr))
                {
                    result.setText("");
                }
                else
                {
                    result.setText("0.00");
                }
            }
    
        }
    
        private boolean isEmpty(String str) {
            return null == str || "".equals(str.trim());
    
        }
        /** * 去空格 * * @param o trim对象 * @return trim后的对象 * @see [类、类#方法、类#成员] */
        public static String trim(Object o)
        {
            String str = "";
            if (null != o)
            {
                str = o.toString().trim();
            }
            return str;
        }
    }

[本文原始代码摘自http://ice-key.iteye.com/blog/1813914][http_ice-key.iteye.com_blog_1813914]

[http_ice-key.iteye.com_blog_1813914]: http://ice-key.iteye.com/blog/1813914