我在我的应用程序中使用了一个保存按钮。当我点击保存按钮时，我希望它验证每个字段并显示错误消息，如＆＃34;请输入此字段＆＃34;，＆＃34;请在此字段中输入正确的格式＆＃34;或＆＃34;请选择此＆＃34;。
我有8个EditText框和2个微调框，而TextView有ListView。在Android中，如何在每个字段上使用字段验证，并在验证每个字段后成功保存数据。
我的java代码是：
public class non_ticket_task extends Activity implements OnItemSelectedListener{
public static String complain_date;
public static String complain_time;
public static String job_performed;
// public static String time;
public static String next_due_on;
static TelephonyManager tm;
// Progress Dialog
private ProgressDialog pDialog;
JSONParser jsonParser = new JSONParser();
TextView cus_name_txt;
EditText complain_date_txtbx;
EditText complain_time_txtbx;
EditText job_performed_txtbx;
EditText date_txtbx;
EditText lat_txtbx;
EditText lon_txtbx;
EditText next_due_on_txtbx;
Button btnadd;
// url to create new product
private static String url_create_task = "http://192.168.2.1/android_connect/create_product.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.non_ticket_task);
this.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
// Buttons
btnadd = (Button) findViewById(R.id.addbtn);
// button click event
btnadd.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// creating new task in background thread
new CreateNewTask().execute();
}
});
cus_name_txt = (TextView)findViewById(R.id.textView1);
cus_name_txt.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Onclick_click1(cus_name_txt);
}
});
complain_date_txtbx = (EditText) findViewById(R.id.complain_date_txt);
complain_date_txtbx.setText(non_ticket_task.complain_date);
complain_time_txtbx = (EditText) findViewById(R.id.complain_time_txt);
complain_time_txtbx.setText(non_ticket_task.complain_time);
job_performed_txtbx = (EditText) findViewById(R.id.job_performed_txt);
job_performed_txtbx.setText(non_ticket_task.job_performed);
date_txtbx = (EditText) findViewById(R.id.date_txt);
date_txtbx.setText(" "
+ String.valueOf(java.text.DateFormat.getDateTimeInstance()
.format(Calendar.getInstance().getTime())));
MyLocation loc = new MyLocation(this.getApplicationContext());
lon_txtbx = (EditText) findViewById(R.id.lon_txt);
lon_txtbx.setText(String.valueOf(loc.lon));
lat_txtbx = (EditText) findViewById(R.id.lat_txt);
lat_txtbx.setText(String.valueOf(loc.lat));
next_due_on_txtbx = (EditText) findViewById(R.id.next_due_on_txt);
next_due_on_txtbx.setText(non_ticket_task.next_due_on);
Spinner status = (Spinner) findViewById(R.id.status_spinner);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.Status_array, android.R.layout.simple_dropdown_item_1line);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
status.setAdapter(adapter);
Spinner severity = (Spinner) findViewById(R.id.severity_spinner);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource(this,
R.array.Severity_array, android.R.layout.simple_dropdown_item_1line);
// Specify the layout to use when the list of choices appears
adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
severity.setAdapter(adapter1);
}
public void onItemSelected(AdapterView<?> parent, View view,
int pos, long id) {
// An item was selected. You can retrieve the selected item using
// parent.getItemAtPosition(pos)
}
public void onNothingSelected(AdapterView<?> parent) {
// Another interface callback
}
public void Onclick_click1(final TextView cus_name_txt)
{
final TextView txtbx = (TextView) cus_name_txt;
if(cus_name_txt.getId()==R.id.textView1)
{
final CharSequence[] items = {"Ali Asghar","Ali Shah","Tamseel","Bilal","Daniyal","Muzamil","Faraz","Uzair","Mohsin","Mehran","Babar","Ameen","Zeeshan","Maqsood","Hasan","Taqi","Talib","Asif","Mudasir"};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Customers Name");
//builder.setI
builder.setItems(items, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
//Toast.makeText(getApplicationContext(), con.get(item).getCountrName(), Toast.LENGTH_SHORT).show();
txtbx.setText(items[item]);
System.out.println("Item is: "+items[item]);
/*CONTRY_ID = con.get(item).getCountryId();
stateET.requestFocus();*/
}
});
builder.show();
}
}
/**
* Background Async Task to Create new product
* */
class CreateNewTask extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(non_ticket_task.this);
pDialog.setMessage("Saving Details..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Creating task
* */
protected String doInBackground(String... args) {
String cus_name = cus_name_txt.getText().toString();
String complain_date = complain_date_txtbx.getText().toString();
String complain_time = complain_time_txtbx.getText().toString();
String job_performed = job_performed_txtbx.getText().toString();
String date = date_txtbx.getText().toString();
String next_due_on = next_due_on_txtbx.getText().toString();
String lat = lat_txtbx.getText().toString();
String lon = lon_txtbx.getText().toString();
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("cus_name", cus_name));
params.add(new BasicNameValuePair("complain_date", complain_date));
params.add(new BasicNameValuePair("complain_time", complain_time));
params.add(new BasicNameValuePair("job_performed", job_performed));
params.add(new BasicNameValuePair("date", date));
params.add(new BasicNameValuePair("next_due_on", next_due_on));
params.add(new BasicNameValuePair("lat", lat));
// getting JSON Object
// Note that create product url accepts POST method
JSONObject json = jsonParser.makeHttpRequest(url_create_task,
"POST", params);
// check log cat fro response
Log.d("Create Response", json.toString());
// check for success tag
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully created product
Intent i = new Intent(getApplicationContext(), My_Task.class);
startActivity(i);
// closing this screen
finish();
} else {
// failed to create product
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once done
pDialog.dismiss();
}
}
答案 0 :(得分：0)
如果我非常了解您，您只需确保向用户提供反馈，以便在EditText中输入内容。如果这是你想要的，那么你只需要检查EditText.getText的长度，如下所示：
if (cus_name_txt.getText().Lenght()==0){
//Your message here
}
希望这有帮助。
答案 1 :(得分：0)
在onPreExecute中，您可以进行验证。如果字段为空（或错误），则将该字段设置为错误消息。如果有一个或多个无效字段，则取消AsyncTask并显示错误。用户修复错误后，可以再次按“保存”。
您应该从onPreExecute中的字段中获取字符串，而不是在doInBackground中，因为您无法从该方法对Ui进行修改。
答案 2 :(得分：0)
坦率地说，验证过程在很大程度上取决于您要验证的内容和方式。例如，如果要在离开焦点后或仅在单击“提交”按钮后验证edittext的文本。 TextWatchers可以实现快速且用户友好的验证。但是，如果要在单击按钮时进行验证，则可以使用类似
的功能boolean void validateInput(){
boolean retStatus=false;
if((textView1.getText().length()==0 || textView1.getText().equals("") && (any other condition )){
retStatus=true;
textView1.setError("You have entered wrong value in textView 1");
}
//similarly for other controls
------
-----
--
return retStatus;
}
如果您想立即使用错误检测，错误检查（和更正）将会很快，而上述方法可能会显示“一次性”错误。您可以决定适合您的用户。
为了减少用户输入错误，请使用edittexts的文本类型，即使用editText的数字作为电话号码，使用姓名的字母或输入电子邮件的emailid等。使用提示指示用户在EditText中应该做什么，即输入您的电子邮件在这里。
快乐编码!!
答案 3 :(得分：0)
你可以像这样创建一个validatefields（）函数并像这样调用这个函数
if(validate()){
new CreateNewTask().execute()
}
else{
showErrorMsg(msg);
}
其中validate函数将是这样的
private boolean validate(){
boolean retStatus=false;
if((textView1.getText().length()==0 || textView1.getText().equals("") ){
retStatus=false;
msg = "Please fill TextView 1";
}
else if ( ---check other 9 condition in the same way--)
}
if ( !msg.equals("")){
return false;
}
else {
return true;
}
}