Java 如何在Android中使用runnable循环
我正在做一个应用程序,其中我必须显示一系列图片:顺序如下:Java 如何在Android中使用runnable循环,java,android,runnable,Java,Android,Runnable,我正在做一个应用程序,其中我必须显示一系列图片:顺序如下: 红色X必须显示至少400毫秒 一张叫做“屏幕截图”的图片必须显示500分钟左右 毫秒 称为“噪音”的图像必须显示50分钟左右 毫秒 “噪波”图像消失,为编辑文本腾出空间 EditText用于获取用户数据 这是我的密码: public class Step1Training extends Activity { ImageFragment myImageFragment; InputFragment myInputFra
X
必须显示至少400毫秒李>
EditText
用于获取用户数据
这是我的密码:
public class Step1Training extends Activity {
ImageFragment myImageFragment;
InputFragment myInputFragment;
Drawable cross;
ImageView myImageView;
EditText myEditText;
int i, length;
String rating;
Handler handler;
boolean continueTask;
int[] screenshots = {
R.drawable.googleplaybooks2,
R.drawable.aldiko1,
R.drawable.chaton2,
R.drawable.cinetrailer1,
R.drawable.fanpage1
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.step1_training);
handler = new Handler();
i = 0;
length = screenshots.length;
initUI();
startThread();
}
private void initUI(){
myImageFragment = (ImageFragment)getFragmentManager().findFragmentById(R.id.imageFragment);
myInputFragment = (InputFragment)getFragmentManager().findFragmentById(R.id.inputFragment);
myImageView = (ImageView)myImageFragment.getView().findViewById(R.id.screenshotImageView);
myImageView.setImageResource(R.drawable.cross300x300);
myEditText = (EditText)myInputFragment.getView().findViewById(R.id.ratingEditText);
myEditText.setVisibility(View.GONE);
}
private void startThread(){
while(i<length){
handler.postDelayed(new TaskScreenshot(i), 250);
handler.postDelayed(new TaskNoise(), 750);
handler.postDelayed(new TaskEditText(), 1000);
myEditText.setOnKeyListener(new View.OnKeyListener(){
public boolean onKey(View v, int keyCode, KeyEvent event) {
if((keyCode == KeyEvent.KEYCODE_ENTER)) {
if(myEditText.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Inserire un numero da 1 a 9", Toast.LENGTH_SHORT).show();
return false;
} else if (Integer.parseInt(myEditText.getText().toString()) >= 1 &&
Integer.parseInt(myEditText.getText().toString()) <= 9){
return true;
}
}
return false;
}
});
System.out.println(i);
i++;
}
}
@Override
public void onBackPressed() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Attenzione")
.setMessage("Sei sicuro/a di voler uscire dall'applicazione?\n" +
"Confermando uscirai dall'applicazione e perderai \n" +
"tutti i dati raccolti finora.")
.setCancelable(false)
.setNegativeButton("No",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
})
.setPositiveButton("Si", new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int whichButton)
{
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
});
AlertDialog alert = builder.create();
alert.show();
}
class TaskScreenshot implements Runnable{
int j;
public TaskScreenshot(int _i){
this.j = _i;
}
@Override
public void run() {
System.out.println("Screenshot");
myEditText.setVisibility(View.GONE);
myImageFragment.getView().setVisibility(View.VISIBLE);
myImageView.setImageResource(screenshots[j]);
myImageView.getLayoutParams().width = LayoutParams.MATCH_PARENT;
myImageView.getLayoutParams().height = LayoutParams.MATCH_PARENT;
}
}
class TaskNoise implements Runnable{
@Override
public void run() {
System.out.println("Noise");
myImageView.setImageResource(R.drawable.noise);
myImageView.getLayoutParams().width = LayoutParams.MATCH_PARENT;
myImageView.getLayoutParams().height = LayoutParams.MATCH_PARENT;
}
}
class TaskEditText implements Runnable{
@Override
public void run() {
System.out.println("EditText");
myEditText.setVisibility(View.VISIBLE);
myImageFragment.getView().setVisibility(View.GONE);
}
}
}
在这个循环中我做错了什么?在用户输入数据之前,如何停止循环
更新1:
我已经按照用户Groco的建议更改了代码:
private void startThread(final int i){
if(i < length){
handler.postDelayed(new TaskScreenshot(i), 250);
handler.postDelayed(new TaskNoise(), 750);
handler.postDelayed(new TaskEditText(), 1000);
myEditText.setOnKeyListener(new View.OnKeyListener(){
public boolean onKey(View v, int keyCode, KeyEvent event) {
if((keyCode == KeyEvent.KEYCODE_ENTER)) {
if(myEditText.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Inserire un numero da 1 a 9", Toast.LENGTH_SHORT).show();
return false;
} else if (Integer.parseInt(myEditText.getText().toString()) >= 1 &&
Integer.parseInt(myEditText.getText().toString()) <= 9){
System.out.println(i);
startThread(i+1);
return true;
}
}
return false;
}
});
}
}
private void startThread(final int i){
如果(i<长度){
handler.postDelayed(新任务截图(i),250);
handler.postDelayed(new tasknise(),750);
postDelayed(新的TaskEditText(),1000);
myEditText.setOnKeyListener(新视图.OnKeyListener(){
公共布尔onKey(视图v、int keyCode、KeyEvent事件){
if((keyCode==KeyEvent.keyCode\u ENTER)){
if(myEditText.getText().toString().equals(“”){
Toast.makeText(getApplicationContext(),“Inserire un numero da 1 a 9”,Toast.LENGTH_SHORT).show();
返回false;
}else如果(Integer.parseInt(myEditText.getText().toString())>=1&&
Integer.parseInt(myEditText.getText().toString())尝试以下操作:
private void startThread(){
while(i<length){
handler.postDelayed(new TaskScreenshot(i), 250);
myEditText.setOnKeyListener(new View.OnKeyListener(){
....
}
}
class TaskScreenshot implements Runnable{
int j;
public TaskScreenshot(int _i){
this.j = _i;
}
@Override
public void run() {
...
handler.postDelayed(new TaskNoise(), 500);
}
}
class TaskNoise implements Runnable{
@Override
public void run() {
...
handler.postDelayed(new TaskEditText(), 250);
}
}
class TaskEditText implements Runnable{
@Override
public void run() {
...
myImageFragment.getView().setVisibility(View.GONE);
}
}
private void startThread(){
而(i您的循环计划一系列事件同时发生。您可能希望在延迟计算中包括i,例如:
handler.postDelayed(new TaskScreenshot(i), i*1500 + 250);
...
更好的方法可能是每个阶段都安排下一个阶段。我还注意到,startThread()函数实际上并不启动新线程。所有事情都发生在主线程上,这是正确的。使用用户交互的结果重新启动一个循环:
private void startThread(int i){
if (i<length){
handler.postDelayed(new TaskScreenshot(i), 250);
handler.postDelayed(new TaskNoise(), 750);
handler.postDelayed(new TaskEditText(), 1000);
myEditText.setOnKeyListener(new View.OnKeyListener(){
public boolean onKey(View v, int keyCode, KeyEvent event) {
if((keyCode == KeyEvent.KEYCODE_ENTER)) {
if(myEditText.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Inserire un numero da 1 a 9", Toast.LENGTH_SHORT).show();
return false;
} else if (Integer.parseInt(myEditText.getText().toString()) >= 1 &&
Integer.parseInt(myEditText.getText().toString()) <= 9){
System.out.println(i);
i++;
startThread(i);
}
}
return false;
}
});
}
return false;
}
private void startThread(inti){
如果(i=1&&
Integer.parseInt(myEditText.getText().toString())为什么while(结果相同)。是的,存在一个错误,根本不应该有while循环。只需添加一个计数器并在TaskEditText类的run方法中使用它。当它达到所需值时,停止摆姿势。类TaskNoise实现Runnable{@Override public void run(){…if(I当我使用变量I
:无法在另一个方法定义的内部类中引用非final变量I
Ah,当然。为参数I添加final->私有void startThread(final int I){…}
。并且不要增加i,而是写入:startThread(i+1);
在调用startThread
之前,确保清空editTextmyEditText.setText(“”)
。我认为在startThread中声明侦听器不是一个好的做法。否则,在调用startThreadmyEditText.setOnKeyListener(null)
之前,请先取消侦听器的设置,或者从方法中声明并将I
设置为成员。您所说的“从方法中声明并将I设置为成员”是什么意思?
private void startThread(int i){
if (i<length){
handler.postDelayed(new TaskScreenshot(i), 250);
handler.postDelayed(new TaskNoise(), 750);
handler.postDelayed(new TaskEditText(), 1000);
myEditText.setOnKeyListener(new View.OnKeyListener(){
public boolean onKey(View v, int keyCode, KeyEvent event) {
if((keyCode == KeyEvent.KEYCODE_ENTER)) {
if(myEditText.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Inserire un numero da 1 a 9", Toast.LENGTH_SHORT).show();
return false;
} else if (Integer.parseInt(myEditText.getText().toString()) >= 1 &&
Integer.parseInt(myEditText.getText().toString()) <= 9){
System.out.println(i);
i++;
startThread(i);
}
}
return false;
}
});
}
return false;
}