电话号码字段应仅接受大于 7 的数字作为 ANDROID 中的第一个字符

Question

我正在 android 中创建一个注册页面，其中包含电话号码字段。 此编辑文本应仅接受大于 6 的数字，即（7,8 或 9）作为第一个字符，如果用户输入小于 7 的数字，则应弹出错误且不应接受该数字。 任何帮助将不胜感激。 提前致谢

在下面粘贴我的代码。

private void numvalidate() {
et5.addTextChangedListener( new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int   i2) {     }

@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
{
}
@Override
public void afterTextChanged(Editable editable) {
Forlessvalues();
}
private String Forlessvalues() {
if (et5.getText().length() == 1 && et5.getText().length() < 10) {

String x = et5.getText().toString();
if (!(x.equals( "7" ) || x.equals( "8" ) || x.equals( "9" ))) {
et5.setError( "Enter Numbers starting with 7,8 or 9" );
return null;
}
}
return null;
}
} );
}

Answer 1

@Override
public void afterTextChanged(Editable editable) {
  if(et5.getText().length()==1){
         if(et5.getText().toString().startsWith("7") ||
            et5.getText().toString().startsWith("8") ||
            et5.getText().toString().startsWith("9")){
          }else{
            te5.setText("");
            et5.setError( "Enter Numbers starting with 7,8 or 9" );
          }
    }
}

最简单的方法。 希望对您有所帮助..

Answer 2

使用正则表达式

声明字符串变量

     String  strExpression = "^[789]\\d{9}$";

if(!yourEdittext.getText().toString().matches(strExpression){
 AlertDialog alertDialog = new AlertDialog.Builder(this).create();
                alertDialog.setIcon(R.drawable.information);
                alertDialog.setTitle("Information");
                alertDialog.setMessage("Please provide valid mobile number.");
                alertDialog.setButton("Ok",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int which) {
                                //dismiss the dialog
                            }
                        });
                alertDialog.show();
}

Answer 3

private void numvalidate() {
 et5.addTextChangedListener( new TextWatcher() {
 @Override
 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int   i2)  {     }

 @Override
 public void onTextChanged(CharSequence s, int start, int before, int count)
 {
 }
 @Override
 public void afterTextChanged(Editable editable) {
   Forlessvalues();
 }
});
}

在numvalidate() 方法之外使用方法Forlessvalues()。

private String Forlessvalues() {
  if (et5.getText().length() > 0 && et5.getText().length() < 10) {

   if (et5.getText().toString().startsWith("7") ||
        et5.getText().toString().startsWith("8") ||
        et5.getText().toString().startsWith("9")) {
        // Code for accept data and return String
   } else {
      et5.setError( "Enter Numbers starting with 7,8 or 9" );
      return null;
   }
 }
 return null;
}

Answer 4

android工作中手机号码第一个字符只有7、8、9位数字开头

源代码 https://drive.google.com/open?id=0BzBKpZ4nzNzUQkU3S25fcXV4cEE

First Letter Start with 7,8,9 in Edit text in android

package com.keshav.mobilenumberrestriction_1_6_digits;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.InputFilter;
import android.text.Spanned;
import android.text.TextWatcher;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    EditText et_mobile_feedback;
    String blockCharacterSet = "1234560";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

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

        et_mobile_feedback.setFilters(new InputFilter[] { filter });

        et_mobile_feedback.addTextChangedListener(new TextWatcher() {

            public void afterTextChanged(Editable s) {
                // you can call or do what you want with your EditText here
            }

            public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

            public void onTextChanged(CharSequence s, int start, int before, int count) {
                if(et_mobile_feedback.getText().toString().length()==0)
                    blockCharacterSet="1234560";
                else
                    blockCharacterSet="";
                if(et_mobile_feedback.getText().toString().length()==10)
                    blockCharacterSet="1234567890";
            }
        });
    }
    private InputFilter filter = new InputFilter() {

        @Override
        public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {

            try {
                if (source != null && blockCharacterSet.contains("" + source.charAt(0))) {
                    return "";
                }
            }catch (StringIndexOutOfBoundsException e){

            }
            return null;
        }
    };
}

    <EditText
        android:id="@+id/et_mobile_feedback"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:editable="true"
        android:fontFamily="sans-serif"
        android:gravity="top"
        android:hint="Mobile"
        android:textColor="@color/colorPrimary"
        android:inputType="number"
        android:maxLength="10"
        android:padding="15dp"
        android:paddingLeft="10dp"
        android:paddingRight="10dp"
        android:paddingTop="10dp"
        android:singleLine="true">