关于java：如何在具有意图的活动之间传递布尔值

How to pass a boolean value between activities with intents

本问题已经有最佳答案，请猛点这里访问。

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public class StartActivity extends AppCompatActivity {

private boolean addition=true;
private boolean subtraction=false;
private boolean multiplication=false;
private boolean division=false;

public static final String ADDITION ="";
public static final String SUBTRACTION ="";
public static final String MULTIPLICATION="";
public static final String DIVISION ="";

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

final Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(myToolbar);

CheckBox additionCheckBox = (CheckBox)findViewById(R.id.additionCheckBox);
CheckBox multiplicationCheckBox = (CheckBox)findViewById(R.id.multiplicationCheckBox);
CheckBox divisionCheckBox = (CheckBox)findViewById(R.id.divisionCheckBox);
CheckBox subtractionCheckBox = (CheckBox)findViewById(R.id.subtractionCheckBox);

Button playButton = (Button)findViewById(R.id.playButton);

additionCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(buttonView.isChecked()){
addition = true;
}else{
addition = false;
}
}
});

multiplicationCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(buttonView.isChecked()){
multiplication = true;
}else{
multiplication= false;
}
}
});

subtractionCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(buttonView.isChecked()){
subtraction = true;
}else{
subtraction = false;
}
}
});

divisionCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(buttonView.isChecked()){
division = true;
}else{
division = false;
}
}
});

playButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(!addition && !subtraction && !multiplication && !division){
final Dialog dialog = new Dialog(StartActivity.this);
dialog.setContentView(R.layout.custom_dialog);
dialog.setTitle("My custom dialog");

//set the custom dialog components - text, image and button
TextView text = (TextView) dialog.findViewById(R.id.textView);
text.setText("Android custom dialog example!");

Button button = (Button) dialog.findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
dialog.dismiss();
}
});

dialog.show();
} else{
Intent i = new Intent(StartActivity.this, Main2Activity.class);
i.putExtra(ADDITION,addition);
i.putExtra(SUBTRACTION,subtraction);
i.putExtra(MULTIPLICATION,multiplication);
i.putExtra(DIVISION,division);
startActivity(i);
}
}
});
}

这是开始活动，我试图向每个基本数学运算发送4个布尔变量，以查看用户检查了哪一个。但是他们在下一次活动中总是假的，我不知道为什么。这是下一个活动：

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public class Main2Activity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);

final Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(myToolbar);

Intent i = getIntent();
Bundle b = i.getExtras();
boolean addition = b.getBoolean("ADDITION");
boolean subtraction = Boolean.getBoolean("SUBTRACTION");
boolean multiplication = b.getBoolean("MULTIPLICATION");
boolean division = b.getBoolean("DIVISION");

int operatorCounter =0;

TextView additionTextView = (TextView) findViewById(R.id.additionTextView);
TextView subtractionTextView = (TextView) findViewById(R.id.subtractionTextView);
TextView multiplicationTextView = (TextView) findViewById(R.id.multiplicationTextView);
TextView divisionTextView = (TextView) findViewById(R.id.divisionTextView);

if (addition) {
additionTextView.setText("addition:checked");
}else{
additionTextView.setText("addition:not checked");
}

if (subtraction) {
subtractionTextView.setText("subtraction:checked");
}else{
subtractionTextView.setText("subtraction:not checked");
}

if (multiplication) {
multiplicationTextView.setText("multiplication:checked");
}else{
multiplicationTextView.setText("multiplication:not checked");
}

if (division) {
divisionTextView.setText("division:checked");
}else{
divisionTextView.setText("division:not checked");
}
}
}

我在文本框中设置文本以查看值是否正确传递但始终为false。对不起代码不好我在android中很新，实际上是android及其学校作业中的第四个迷你项目。

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我看到的问题是id：

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public static final String ADDITION ="";
public static final String SUBTRACTION ="";
public static final String MULTIPLICATION="";
public static final String DIVISION ="";

这应该是一些不同的东西，如：

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public static final String ADDITION ="ADDITION";
public static final String SUBTRACTION ="SUBTRACTION";
public static final String MULTIPLICATION="MULTIPLICATION";
public static final String DIVISION ="DIVISION";

并使用相同的值来检索其他活动中的值

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Intent intt = new Intent(this，YourAcivity.class);

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intt.putExtra("BooleanKey",true);
startActivity(intt);

protected void onCreate(Bundle savedInstanceState) {
Boolean yourBool = getIntent().getExtras().getBoolean("yourBoolName");

}

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我希望代码可以帮到你
Intent intent = new Intent(this，NextActivity.class);
intent.putExtra("yourBoolName"，true);

1 2	protected void onCreate(Bundle savedInstanceState) { Boolean yourBool = getIntent().getExtras().getBoolean("yourBoolName");

}

我将使用这篇文章来说明为什么mcve是有用的，因为这是一个完美的例子，我将使用他的代码，清理无用的部分，我们将很快找到问题，我不配或要求upvote但不要如果您反对这个答案，请注意，如果需要，我会删除它。

所以，让我们清理代码，我只对这里的Intent创建感兴趣。因此，请清理其余部分并保留使用的变量/常量。为了最小化，我们只需要一个布尔值，让我们保留第一个putBoolean。

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public class StartActivity extends AppCompatActivity {

private boolean addition=true;

public static final String ADDITION ="";

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

Button playButton = (Button)findViewById(R.id.playButton);

playButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(StartActivity.this, Main2Activity.class);
i.putExtra(ADDITION,addition);
startActivity(i);
}
});

嗯，这样更好。适合一个屏幕，我们直接看到问题。

恢复相同：

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嗯，可以在这里使用StartActivity.ADDITION ......

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Intent intent = new Intent(this, NextActivity.class);
intent.putExtra("BoolName", true);
startActivity(intent );

从intent中检索布尔值：

1	Boolean yourBool = getIntent().getExtras().getBoolean("BoolName");

确保使用相同的键来放置和获取数据。

还要更新

1	boolean subtraction = Boolean.getBoolean("SUBTRACTION");

至

1	boolean subtraction = b.getBoolean("SUBTRACTION");

因为你没有在全局变量中设置值，所以你需要像这样设置第一个全局变量值

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然后设置它

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Intent i = new Intent(StartActivity.this, Main2Activity.class);
i.putExtra(ADDITION,addition);
i.putExtra(SUBTRACTION,subtraction);
i.putExtra(MULTIPLICATION,multiplication);
i.putExtra(DIVISION,division);
startActivity(i);

而不是像这样的另一个活动的aceess值

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boolean addition = getIntent().getExtras().getBoolean("ADDITION");
boolean sub = getIntent().getExtras().getBoolean("SUBTRACTION");
boolean mult = getIntent().getExtras().getBoolean("MULTIPLICATION");
boolean division = getIntent().getExtras().getBoolean("DIVISION");

尝试使用此代码发送和获取值;

传递给第一个活动：

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Intent i = new Intent(getBaseContext(), NameOfActivity.class);
i.putExtra("my_boolean_key", myBooleanVariable);
startActivity(i);

检索第二个活动：

1 2	Bundle bundle = getIntent().getExtras(); boolean myBooleanVariable = bundle.getBoolean("my_boolean_key");

希望这可以帮助你

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