我想创建一个应用程序，其想法是单击按钮并更改图像。每次我单击按钮时，imageview都会更改（动态imageview）。我正在尝试这样做，但是当我运行第一个imageview下方的代码时，当我按下按钮时，第一个imageview跳转到最后一个imageview，而忽略其中的两个imageview。怎么了？
这是我的代码：
SEGUNDATELA. JAVA:
public class SegundaTela extends AppCompatActivity {
private Integer [] imagens = new Integer[]{R.drawable.tabeladia2, R.drawable.tabeladia3, R.drawable.tabeladia4, R.drawable.tabeladia5};
private RadioGroup radioGroup;
private RadioButton sim;
private RadioButton nao;
private Button proxima;
private ImageView img;
private int i=0;
private Integer [] dados= new Integer[4];
private int soma =0;
private int j;
private int inicio;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_segunda_tela);
img = findViewById(R.id.imageView);
proxima = findViewById(R.id.proximaId);
radioGroup = findViewById(R.id.RadioGroupId);
sim = findViewById(R.id.simId);
nao = findViewById(R.id.naoId);
if (sim.isChecked()) {
inicio = 1;
} else if (nao.isChecked()) {
inicio = 0;
}
proxima.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (i < 4) {
++i;
j = (i - 1);
switch (j) {
case 0:
if (sim.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 2;
} else if (nao.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 0;
}
break;
case 1:
if (sim.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 4;
} else if (nao.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 0;
}
break;
case 2:
if (sim.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 8;
} else if (nao.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 0;
}
break;
case 3:
if (sim.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 16;
} else if (nao.isChecked()) {
img.setImageResource(imagens[j]);
dados[j] = 0;
}
break;
}
radioGroup.clearCheck();
} else {
soma = dados[0] + dados[1] + dados[2] + dados[3] + inicio;
Intent i = new Intent(SegundaTela.this, MainActivity.class);
i.putExtra("soma", soma);
startActivity(i);
}
}
});
}
}
SEGUNDATELA.MML
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Button
android:id="@+id/proximaId"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:layout_marginBottom="8dp"
android:text="proxima"
app:layout_constraintBottom_toTopOf="@+id/imageView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
android:scaleType="fitXY"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="@drawable/tabeladia1" />
<RadioGroup
android:id="@+id/RadioGroupId"
android:layout_width="98dp"
android:layout_height="86dp"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toTopOf="@+id/imageView"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<RadioButton
android:id="@+id/simId"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Sim" />
<RadioButton
android:id="@+id/naoId"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Não" />
</RadioGroup>
答案 0 :(得分：1)
每次执行onClick（）时，都会执行整个for循环。这就是为什么。如果您只希望它一次只能处理一张图像，则需要找到一种不同的解决方案，使您可以在两次“单击”之间保持状态（知道当前图像）。
答案 1 :(得分：0)
您需要删除for循环并在每次单击按钮时递增。
如果要循环显示图像，请使用此选项。
public class MainActivity extends AppCompatActivity {
private int [] imagens = {R.drawable.tabeladia2, R.drawable.tabeladia3,
R.drawable.tabeladia4, R.drawable.tabeladia5};
private Button proxima;
private ImageView img;
private Integer currentImg;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
proxima = findViewById(R.id.proximaId);
img = findViewById(R.id.imageView);
proxima.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (currentImg != null && currentImg < 3) {
currentImg++;
} else {
currentImg = 0;
}
img.setImageResource(imagens[currentImg]);
}
});
}
}
如果您不希望图像循环播放，请使用此选项
public class MainActivity extends AppCompatActivity {
private int [] imagens = {R.drawable.tabeladia2, R.drawable.tabeladia3,
R.drawable.tabeladia4, R.drawable.tabeladia5};
private Button proxima;
private ImageView img;
private Integer currentImg;
private int[] intArray = new int[4];
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
proxima = findViewById(R.id.proximaId);
img = findViewById(R.id.imageView);
proxima.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (currentImg != null) {
if (currentImg < 3) {
currentImg++;
if(currentImg == 1){
intArray[1] = 2;
}else if(currentImg == 2){
intArray[2] = 4;
}else if(currentImg == 3){
intArray[3] = 8;}
img.setImageResource(imagens[currentImg]);
}else{
//handle last image reached condition
Toast.makeText(MainActivity.this, "Last image reached", Toast.LENGTH_SHORT).show();
}
} else {
currentImg = 0;
intArray[0] = 1;
img.setImageResource(imagens[currentImg]);
}
}
});
}
}
使用案例声明和单选按钮。
public class SegundaTela extends AppCompatActivity {
private Integer[] imagens = new Integer[]{R.drawable.tabeladia2, R.drawable.tabeladia3, R.drawable.tabeladia4, R.drawable.tabeladia5};
private RadioGroup radioGroup;
private RadioButton sim;
private RadioButton nao;
private Button proxima;
private ImageView img;
private Integer i;
private int soma = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_segunda_tela);
img = findViewById(R.id.imageView);
proxima = findViewById(R.id.proximaId);
radioGroup = findViewById(R.id.RadioGroupId);
sim = findViewById(R.id.simId);
nao = findViewById(R.id.naoId);
proxima.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!sim.isChecked() && !nao.isChecked()) {
Toast.makeText(SegundaTela.this, "Select an option", Toast.LENGTH_SHORT).show();
return;
}
if (i != null) {
if (i < 5) {
switch (i) {
case 0:
if (sim.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 2;
soma = soma + 2;
} else if (nao.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 0;
soma = soma + 0;
}
break;
case 1:
if (sim.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 4;
soma = soma + 4;
} else if (nao.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 0;
soma = soma + 0;
}
break;
case 2:
if (sim.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 8;
soma = soma + 8;
} else if (nao.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 0;
soma = soma + 0;
}
break;
case 3:
if (sim.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 16;
soma = soma + 16;
} else if (nao.isChecked()) {
img.setImageResource(imagens[i]);
//dados[j] = 0;
soma = soma + 0;
}
break;
case 4:
/*if (sim.isChecked()) {
//dados[j] = 16;
soma = soma + 32;
} else if (nao.isChecked()) {
//dados[j] = 0;
soma = soma + 0;
}*/
Intent i = new Intent(SegundaTela.this, MainActivity.class);
i.putExtra("soma", soma);
startActivity(i);
break;
}
++i;
Toast.makeText(SegundaTela.this, "soma: " + soma, Toast.LENGTH_SHORT).show();
radioGroup.clearCheck();
} /*else {
//soma = dados[0] + dados[1] + dados[2] + dados[3] + inicio;
Intent i = new Intent(SegundaTela.this, MainActivity.class);
i.putExtra("soma", soma);
startActivity(i);
}*/
}else {
if (sim.isChecked()) {
//inicio = 1;
soma = soma + 1;
} else if (nao.isChecked()) {
//inicio = 0;
soma = soma + 0;
}
i = 0;
radioGroup.clearCheck();
}
}
});
}
}