Question

在Android Studio 2.3中使用约束布局

尝试实现：在屏幕上显示一个按钮，并隐藏布局中的所有其他元素。在该按钮上单击，显示所有其他元素，但隐藏按钮本身。

已实现：使用布局嵌套，如果我将按钮放在一个布局中，则将其设置为在开始时可见，并将所有元素放在另一个布局中。我可以解决上述问题。

问题：我希望在没有嵌套布局的情况下实现这一点，否则就是使用约束布局。任何人吗？

public class MainActivity extends AppCompatActivity {
Button startButton,playButton;
TextView timerTextView;
TextView resultTextView;
Button button0,button1,button2,button3;
TextView sumTextView;
TextView pointsTextView;
ArrayList<Integer> answers = new ArrayList<Integer>();
int locationOfCorrectAnswer;
int score=0;
int numberOfQuestions=0;
ConstraintLayout mainLayout;

public void playAgain(View view)
{
    score = 0;
    numberOfQuestions = 0;

    timerTextView.setText("30s");
    pointsTextView.setText("0/0");
    resultTextView.setText("");
    playButton.setVisibility(View.INVISIBLE);
    generateQuestion();

    new CountDownTimer(30100,1000){

        @Override
        public void onTick(long millisUntilFinished) {
            timerTextView.setText(String.valueOf(millisUntilFinished/1000) + "s");

        }

        @Override
        public void onFinish() {

            timerTextView.setText("0s");
            playButton.setVisibility(View.VISIBLE);
            resultTextView.setText("Your score is " + Integer.toString(score)+ " / " + Integer.toString(numberOfQuestions));

        }
    }.start();

}

public void generateQuestion()
{
    Random rand= new Random();

    int a = rand.nextInt(21);
    int b = rand.nextInt(21);

    sumTextView.setText(Integer.toString(a)+ " + " + Integer.toString(b));
    locationOfCorrectAnswer = rand.nextInt(4);
    answers.clear();

    int incorrectAnswer;

    for(int i=0; i <4 ; i++)
    {
        if(i==locationOfCorrectAnswer)
        {
            answers.add(a + b);
        }
        else
        {
            incorrectAnswer = rand.nextInt(41);

            while ( incorrectAnswer == a + b)
            {
                incorrectAnswer = rand.nextInt(41);
            }
            answers.add(incorrectAnswer);
        }
    }
    button0.setText(Integer.toString(answers.get(0)));
    button1.setText(Integer.toString(answers.get(1)));
    button2.setText(Integer.toString(answers.get(2)));
    button3.setText(Integer.toString(answers.get(3)));
}

public void chooseAnswer(View view)
{
    if(view.getTag().toString().equals(Integer.toString(locationOfCorrectAnswer)))
    {
        score++;
        resultTextView.setText("Correct!");

    }
    else
    {
        resultTextView.setText("Wrong!");
    }
    numberOfQuestions++;
    pointsTextView.setText(Integer.toString(score)+"/"+ Integer.toString(numberOfQuestions));
    generateQuestion();
}

public void start(View view)
{
    startButton.setVisibility(View.INVISIBLE);
    mainLayout.setVisibility(View.VISIBLE);
    playAgain(findViewById(R.id.playButton));

}

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

    startButton = (Button) findViewById(R.id.startButton);
    sumTextView = (TextView) findViewById(R.id.sumTextView);
    button0 = (Button) findViewById(R.id.button2);
    button1 = (Button) findViewById(R.id.button3);
    button2 = (Button) findViewById(R.id.button4);
    button3 = (Button) findViewById(R.id.button5);
    resultTextView = (TextView) findViewById(R.id.resultTextView);
    pointsTextView = (TextView) findViewById(R.id.pointsTextView);
    timerTextView = (TextView) findViewById(R.id.timerTextView);
    playButton= (Button) findViewById(R.id.playButton);
    mainLayout = (ConstraintLayout) findViewById(R.id.mainLayout);


}

}

Answer 1

您可以在点击按钮时设置元素的可见性。这方面的一个例子是：

button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
    button.setVisibility(View.GONE);  //hide button
    layout.setVisibility(View.VISIBLE);  //show some layout
    textview.setVisibility(View.VISIBLE); //show some textview
    ....

}
});

如果要在布局中保留按钮的空间，请使用View.INVISIBLE。如果按钮在不可见后不应占用布局中的任何空格，请使用View.GONE。

在Constraint Layout中单击按钮时隐藏并显示整个屏幕

1 个答案: