尝试将字符串值恢复到文本视图中的意图附加功能

Question

我对 android studio 中的编程很陌生，似乎无法让我的应用程序将意图值恢复到文本视图中。

我有一个问题活动，其中用户被问到一些问题，这些问题是使用是/否单选按钮回答的。从这里已经进行了高级诊断，因此诊断存储在问题活动中到我的"storeintent(("方法中。问题是，当使用"restoreintents(("方法在答案活动中调用意图时，文本视图中不会显示任何内容。

以下是问题活动(答案已存储，请查看评论(：

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.Toast;
public class Questions extends AppCompatActivity {
private Button button2;
private RadioButton radioButton;
private RadioButton radioButton2;
private RadioButton radioButton3;
private RadioButton radioButton4;
private RadioButton radioButton5;
private RadioButton radioButton6;
private RadioButton radioButton7;
private RadioButton radioButton8;
private RadioButton radioButton9;
private RadioButton radioButton10;
private RadioButton radioButton11;
private RadioButton radioButton12;
private RadioButton radioButton13;
private RadioButton radioButton14;
private RadioButton radioButton15;
private RadioButton radioButton16;
private RadioButton radioButton17;
private RadioButton radioButton18;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_questions);
storeintent();
button2 = findViewById(R.id.button2);
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
opendiagnosis();
storeintent();
}
});
//Question 1
radioButton = findViewById(R.id.radioButton); //yes
radioButton2 = findViewById(R.id.radioButton20); //no
//Question 2
radioButton3 = findViewById(R.id.radioButton4); //yes
radioButton4 = findViewById(R.id.radioButton2); //no
//Question 3
radioButton5 = findViewById(R.id.radioButton6); //yes
radioButton6 = findViewById(R.id.radioButton5); //no
//Question 4
radioButton7 = findViewById(R.id.radioButton7); //yes
radioButton8 = findViewById(R.id.radioButton8); //no
//Question 5
radioButton9 = findViewById(R.id.radioButton9); //yes
radioButton10 = findViewById(R.id.radioButton10); //no
//Question 6
radioButton11 = findViewById(R.id.radioButton12); //yes
radioButton12 = findViewById(R.id.radioButton11); //no
//Question 7
radioButton13 = findViewById(R.id.radioButton13); //yes
radioButton14 = findViewById(R.id.radioButton14); //no
//Question 8
radioButton15 = findViewById(R.id.radioButton15); //yes
radioButton16 = findViewById(R.id.radioButton16); //no
//Question 9
radioButton17 = findViewById(R.id.radioButton17); //yes
radioButton18 = findViewById(R.id.radioButton18); //no
}
public void storeintent() {
String value="Android Studio Is TERRIBLE"; //my string to be displayed in textView16 in the answers activity
Intent i = new Intent(this, Questions.class);
i.putExtra("key",value);
startActivity(i);
}
public void opendiagnosis() {
// for all pairs: one of each pair has to be checked
boolean shouldStartNextActivity = (radioButton.isChecked() || radioButton2.isChecked())
&& (radioButton3.isChecked() || radioButton4.isChecked()) && (radioButton5.isChecked() || radioButton6.isChecked())
&& (radioButton7.isChecked() || radioButton8.isChecked())&& (radioButton9.isChecked() || radioButton10.isChecked())
&& (radioButton11.isChecked() || radioButton12.isChecked())&& (radioButton13.isChecked() || radioButton14.isChecked())
&& (radioButton15.isChecked() || radioButton16.isChecked())&& (radioButton17.isChecked() || radioButton18.isChecked());

if (shouldStartNextActivity){
Intent intent = new Intent(this, answers.class);
startActivity(intent);
} else{
Toast.makeText(getBaseContext(), "Please answer all the questions for an accurate diagnosis", Toast.LENGTH_LONG).show();
}
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);

savedInstanceState.putBoolean("myOption1", radioButton.isChecked());
savedInstanceState.putBoolean("myOption2", radioButton2.isChecked());
savedInstanceState.putBoolean("myOption3", radioButton3.isChecked());
savedInstanceState.putBoolean("myOption4", radioButton4.isChecked());
savedInstanceState.putBoolean("myOption5", radioButton5.isChecked());
savedInstanceState.putBoolean("myOption6", radioButton6.isChecked());
savedInstanceState.putBoolean("myOption7", radioButton7.isChecked());
savedInstanceState.putBoolean("myOption8", radioButton8.isChecked());
savedInstanceState.putBoolean("myOption9", radioButton9.isChecked());
savedInstanceState.putBoolean("myOption10", radioButton10.isChecked());
savedInstanceState.putBoolean("myOption11", radioButton11.isChecked());
savedInstanceState.putBoolean("myOption12", radioButton12.isChecked());
}
@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
radioButton.setChecked(savedInstanceState.getBoolean("myOption1"));
radioButton2.setChecked(savedInstanceState.getBoolean("myOption2"));
radioButton3.setChecked(savedInstanceState.getBoolean("myOption3"));
radioButton4.setChecked(savedInstanceState.getBoolean("myOption4"));
radioButton5.setChecked(savedInstanceState.getBoolean("myOption5"));
radioButton6.setChecked(savedInstanceState.getBoolean("myOption6"));
radioButton7.setChecked(savedInstanceState.getBoolean("myOption7"));
radioButton8.setChecked(savedInstanceState.getBoolean("myOption8"));
radioButton9.setChecked(savedInstanceState.getBoolean("myOption9"));
radioButton10.setChecked(savedInstanceState.getBoolean("myOption10"));
radioButton11.setChecked(savedInstanceState.getBoolean("myOption11"));
radioButton12.setChecked(savedInstanceState.getBoolean("myOption12"));
}
}

以下是答案活动(其中诊断旨在通过调用意图来检索，但不是，请参阅所做的评论(：

public class answers extends AppCompatActivity {
private Button button7;

private TextView textView;
private TextView textView2;
private TextView textView3;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_answers);
restoreintents(); //method CALLED HERE!
button7 = findViewById(R.id.button7);
button7.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
reset();
}
});

textView = findViewById(R.id.textView16);
textView2 = findViewById(R.id.textView17);
textView3 = findViewById(R.id.textView18);
}
public void restoreintents() {
Bundle extras = getIntent().getExtras(); //Questions intent is called here again
if (extras != null) {
String value = extras.getString("key");
//The key argument here must match that used in the other activity
textView.setText(value); //String does not appear in textbox, it stays empty
}
}

public void reset() {
Intent intent = new Intent(this, Questions.class);
startActivity(intent);
}
}

一些帮助将不胜感激！

Answer 1

为什么不使用intent.putExtra(key，value(，然后在目标活动中获取这些发送的信息，并使用getExtra(key(函数获取它们。 你可以这样做：

Intent i = new Intent(context, MyActivity.class);   
String value  = "some string";
i.putExtra("KEY_STRING", value );

并在"我的活动"中获取它：

Bundle bundle = getIntent().getExtras();
if(bundle.getString("KEY_STRING")!= null) {
String str = intent.getStringExtra("KEY_STRING");
}

Answer 2

您忘记将值传递给答案类，替换问题类中的以下代码

if (shouldStartNextActivity){
Intent intent = new Intent(this, answers.class);
intent.putExtra("key", value);
startActivity(intent);
} else{
Toast.makeText(getBaseContext(), "Please answer all the questions for an accurate diagnosis", Toast.LENGTH_LONG).show();
}

同样，您还需要在答案类中放置额外的内容

public void reset() {
Intent intent = new Intent(this, Questions.class);
intent.putExtra("key", textView.getText());
startActivity(intent);
}

Answer 3

您忘记在方法中添加额外的意图opendiagnosis()按如下方式更改代码：

public void opendiagnosis() {
// for all pairs: one of each pair has to be checked
boolean shouldStartNextActivity = (radioButton.isChecked() || radioButton2.isChecked())
&& (radioButton3.isChecked() || radioButton4.isChecked()) && (radioButton5.isChecked() || radioButton6.isChecked())
&& (radioButton7.isChecked() || radioButton8.isChecked())&& (radioButton9.isChecked() || radioButton10.isChecked())
&& (radioButton11.isChecked() || radioButton12.isChecked())&& (radioButton13.isChecked() || radioButton14.isChecked())
&& (radioButton15.isChecked() || radioButton16.isChecked())&& (radioButton17.isChecked() || radioButton18.isChecked());

if (shouldStartNextActivity){
String value="Android Studio Is TERRIBLE"; 
Intent intent = new Intent(this, answers.class);
intent.putExtra("key",value);
startActivity(intent);
} else{
Toast.makeText(getBaseContext(), "Please answer all the questions for an accurate 
diagnosis", Toast.LENGTH_LONG).show();
}
}