我正在创建一个应用程序，它将从用户那里获取输入并将其发送到服务器进行搜索。这是我的两个问题
这是我的代码
public class QuickSearch extends Activity {
Button search;
RadioGroup stones;
RadioButton single,twin,selected_value;
EditText to,from,unique_id;
TextView tv;
HttpPost httppost;
StringBuffer buffer;
HttpResponse response;
HttpClient httpclient;
List<NameValuePair> nameValuePairs;
ProgressDialog dialog = null;
Intent f1;
String radiovalue;
String str_color1,str_color2,str_clarity1, str_clarity2, str_shape1,str_shape2, str_cut1,str_cut2,str_carat1,str_carat2;
Spinner color1,color2,shape1,shape2,clarity1,clarity2,cut,cut2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_quicksearch);
search=(Button)findViewById(R.id.search);
// submit=(Button)findViewById(R.id.submit);
to=(EditText)findViewById(R.id.to);
from=(EditText)findViewById(R.id.from);
// unique_id=(EditText)findViewById(R.id.unique_id);
tv = (TextView)findViewById(R.id.tv);
stones=(RadioGroup)findViewById(R.id.radioGroup);
single=(RadioButton)findViewById(R.id.single);
twin=(RadioButton)findViewById(R.id.twin);
f1 = new Intent(QuickSearch.this,Search_result.class);
color1=(Spinner)findViewById(R.id.color1);
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.color1, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
color1.setAdapter(adapter);
color2=(Spinner)findViewById(R.id.color2);
ArrayAdapter<CharSequence> adapter2 = ArrayAdapter.createFromResource(this, R.array.color2, android.R.layout.simple_spinner_item);
adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
color2.setAdapter(adapter2);
shape1=(Spinner)findViewById(R.id.shape);
ArrayAdapter<CharSequence> adapter3 = ArrayAdapter.createFromResource(this, R.array.shape, android.R.layout.simple_spinner_item);
adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
shape1.setAdapter(adapter3);
shape2=(Spinner)findViewById(R.id.shape2);
ArrayAdapter<CharSequence> adapter8 = ArrayAdapter.createFromResource(this, R.array.shape2, android.R.layout.simple_spinner_item);
adapter8.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
shape2.setAdapter(adapter8);
clarity1=(Spinner)findViewById(R.id.clarity1);
ArrayAdapter<CharSequence> adapter4 = ArrayAdapter.createFromResource(this,
R.array.clarity1, android.R.layout.simple_spinner_item);
adapter4.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
clarity1.setAdapter(adapter4);
clarity2=(Spinner)findViewById(R.id.clarity2);
ArrayAdapter<CharSequence> adapter5 = ArrayAdapter.createFromResource(this,R.array.clarity2, android.R.layout.simple_spinner_item);
adapter5.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
clarity2.setAdapter(adapter5);
cut=(Spinner)findViewById(R.id.cut);
ArrayAdapter<CharSequence> adapter6 = ArrayAdapter.createFromResource(this,R.array.cut, android.R.layout.simple_spinner_item);
adapter6.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
cut.setAdapter(adapter6);
cut2=(Spinner)findViewById(R.id.cut2);
ArrayAdapter<CharSequence> adapter7 = ArrayAdapter.createFromResource(this,R.array.cut2, android.R.layout.simple_spinner_item);
adapter7.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
cut2.setAdapter(adapter7);
/*
if(stones.getCheckedRadioButtonId()!=-1){
int id= stones.getCheckedRadioButtonId();
View radioButton = stones.findViewById(id);
// int radioId = radioGroup.indexOfChild(radioButton);
RadioButton btn = (RadioButton) stones.getChildAt(radioId);
radiovalue = (String) btn.getText();
}
*/
//--------------------------------getting value on button press------------------
search.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
str_color1= color1.getSelectedItem().toString();
str_color2= color2.getSelectedItem().toString();
str_shape1=shape1.getSelectedItem().toString();
str_shape2=shape2.getSelectedItem().toString();
str_clarity2=clarity2.getSelectedItem().toString();
str_clarity1= clarity1.getSelectedItem().toString();
str_cut1=cut.getSelectedItem().toString();
str_cut2=cut2.getSelectedItem().toString();
str_carat1=to.getText().toString().trim();
str_carat2=from.getText().toString().trim();
dialog = ProgressDialog.show(QuickSearch.this, "","Searching...", true);
int selectedId = stones.getCheckedRadioButtonId();
// find the radiobutton by returned id
selected_value = (RadioButton) findViewById(selectedId);
radiovalue= selected_value.getText().toString();
if(str_color1=="Color To:" || str_color2=="Color From:" || str_clarity1=="Color To:" || str_clarity2 =="Color From:"
|| str_cut1 == "Cut To:" || str_cut2 == " Cut From:" || str_shape1=="Shape To:" || str_shape2 =="Shape From"
|| radiovalue=="" || str_carat1==null || str_carat2==null)
{
Toast.makeText(getApplicationContext(), "Please enter all the field", Toast.LENGTH_SHORT).show();
}
else
{
new Thread(new Runnable() {
public void run() {
Search();
}
}).start();
}}
});
}
void Search(){
try{
httpclient=new DefaultHttpClient();
httppost= new HttpPost("http://192.168.43.6/test/search.php"); // make sure the url is correct.
//add your data
nameValuePairs = new ArrayList<NameValuePair>(2);
// Always use the same variable name for posting i.e the android side variable name and php side variable name should be similar,
nameValuePairs.add(new BasicNameValuePair("carat1",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("carat2",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("color1",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("color2",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("shape1",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("shape2",unique_id.getText().toString().trim()));
nameValuePairs.add(new BasicNameValuePair("stones",unique_id.getText().toString().trim()));
// $Edittext_value = $_POST['Edittext_value'];
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
//Execute HTTP Post Request
response=httpclient.execute(httppost);
ResponseHandler<String> responseHandler = new BasicResponseHandler();
final String response = httpclient.execute(httppost, responseHandler);
System.out.println("Response : " + response);
runOnUiThread(new Runnable() {
public void run() {
tv.setText("Response from PHP : " + response);
dialog.dismiss();
}
});
if(response.equalsIgnoreCase("Search")){
runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(QuickSearch.this, "Searching Successful", Toast.LENGTH_SHORT).show();
}
});
// startActivity(new Intent(QuickSearch.this, LoginScreen.class));
//f1.putExtra("unique_id", unique_id.getText());
//st/artActivity(f1);
}else{
showAlert();
}
}catch(Exception e){
dialog.dismiss();
System.out.println("Exception : " + e.getMessage());
}
}
public void showAlert(){
QuickSearch.this.runOnUiThread(new Runnable() {
public void run() {
AlertDialog.Builder builder = new AlertDialog.Builder(QuickSearch.this);
builder.setTitle("Searching Error.");
builder.setMessage("Problem in Searching. Please try again later")
.setCancelable(false)
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
}
});
AlertDialog alert = builder.create();
alert.show();
}
});
}
}
logcat错误
05-15 11:13:22.327 28644-28932/com.diamond.traders I/System.out﹕ Exception : Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference
答案 0 :(得分：2)
您已注释掉初始化unique_id EditText实例的行：
// unique_id=(EditText)findViewById(R.id.unique_id);
所以在打电话时
nameValuePairs.add(new BasicNameValuePair("carat1",unique_id.getText().toString().trim()));
它会引发异常。
正确初始化gui元素以便能够访问它们。