Question

我是新的android / java学生我尝试制作测试应用程序但是我遇到了问题并且搜索了它但没有解决我创建了一个新的xml文件（应用程序的新屏幕），我想在新的java类中使用xml元素。

搜索后尝试使用Inflator但没有工作没有错误但没有返回所需的值。请帮忙。

* Main Class.java

package online.pharmastars.dosecalculator;

            import android.content.Intent;
            import android.support.v7.app.AppCompatActivity;
            import android.os.Bundle;
            import android.view.View;
            import android.widget.AdapterView;
            import android.widget.ArrayAdapter;
            import android.widget.Spinner;
            import android.widget.Toast;

            public class MainActivity extends AppCompatActivity {

                @Override
                protected void onCreate(Bundle savedInstanceState) {
                    super.onCreate(savedInstanceState);
                    setContentView(R.layout.activity_main);
                    Spinner spinner = (Spinner) findViewById(R.id.drug_spinner);
                    // Create an ArrayAdapter using the string array and a default spinner layout
                    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
                            R.array.drugs_array, android.R.layout.simple_spinner_item);
                    // 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
                    spinner.setAdapter(adapter);
                }
                String selectedDrug = "";
                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)
                    selectedDrug = parent.getItemAtPosition(pos).toString();
                }

                public void onNothingSelected(AdapterView<?> parent) {
                    // Another interface callback
                }

                public void calculateDose(View view){
                    Intent doseCalculate = new Intent(this, DoseCalculation.class);
                    startActivity(doseCalculate);
                }
            }

新的class.java是：

package online.pharmastars.dosecalculator;

            import android.app.Activity;
            import android.content.Context;
            import android.os.Bundle;
            import android.support.v7.app.AppCompatActivity;
            import android.view.LayoutInflater;
            import android.view.View;
            import android.widget.EditText;
            import android.widget.TextView;

            import static online.pharmastars.dosecalculator.R.id.weight;

            /**
             * Created by ahmed on 4/24/2017.
             */

            public class DoseCalculation extends AppCompatActivity {
                @Override
                protected void onCreate(Bundle savedInstanceState) {
                    super.onCreate(savedInstanceState);
                    setContentView(R.layout.dose_calculation);
                    calculateDose();
                }

                public void calculateDose(){
                    LayoutInflater layoutInflater = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    View view = layoutInflater.inflate(R.layout.activity_main, null);
                    EditText pWeight = (EditText) view.findViewById(R.id.age_years);
                    String test = pWeight.getText().toString();
                    TextView patientWeight = (TextView) findViewById(R.id.text_view_weight);
                    patientWeight.setText(test);
                }
            }

Answer 1

我想您忘记在onCreate方法中打开新方法的方法

            @Override
            protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_main);
                Spinner spinner = (Spinner) findViewById(R.id.drug_spinner);
                // Create an ArrayAdapter using the string array and a default spinner layout
                ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
                        R.array.drugs_array, android.R.layout.simple_spinner_item);
                // 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
                spinner.setAdapter(adapter);
                calculateDose();

            }

并像这样修改您的方法

 public void calculateDose(View view){
                    Intent doseCalculate = new Intent(this, DoseCalculation.class);
                    startActivity(doseCalculate);
                }

并且在calculateDose方法中，不需要参数View

在另一个新类中调用来自Xml类的视图

1 个答案: