Android 在设置ViewPager适配器之前异步调用并向片段传递值
我在MainActivity类中有一个SlideTabLayout。我正在活动中执行异步网络操作,并将获取的结果传递给SlideTabLayout中所需的片段。但适配器正在将片段设置为null值,我的网络操作稍后将获取数据,因为我无法将值传递给片段。如果您可以看到下面的代码。ArrayList值在初始阶段为0,并且活动正在将null值传递给所有片段。之后,ArrayList值将得到更新,但不会传递给片段Android 在设置ViewPager适配器之前异步调用并向片段传递值,android,android-fragments,android-asynctask,android-viewpager,Android,Android Fragments,Android Asynctask,Android Viewpager,我在MainActivity类中有一个SlideTabLayout。我正在活动中执行异步网络操作,并将获取的结果传递给SlideTabLayout中所需的片段。但适配器正在将片段设置为null值,我的网络操作稍后将获取数据,因为我无法将值传递给片段。如果您可以看到下面的代码。ArrayList值在初始阶段为0,并且活动正在将null值传递给所有片段。之后,ArrayList值将得到更新,但不会传递给片段 protected void onCreate(Bundle savedInstanceSt
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_meat);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
CatalogueService catalogueService = App42API.buildCatalogueService();
Intent categoryIntent = getIntent();
catalogueName = categoryIntent.getStringExtra("CATALOGUE");
viewPager = (ViewPager) findViewById(R.id.viewpager_meat);
tabLayout = (TabLayout) findViewById(R.id.tabs_meat);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(MeatActivity.this,CartActivity.class);
startActivity(intent);
}
});
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
String chickenCategoryName = "Chicken";
catalogueService.getItemsByCategory(catalogueName, chickenCategoryName, new App42CallBack() {
@Override
public void onSuccess(Object o) {
Catalogue catalogue = (Catalogue) o;
for (int i = 0; i < catalogue.getCategoryList().size(); i++) {
String category = catalogue.getCategoryList().get(i).getName();
if (category.equals("Chicken")) {
chickenList = catalogue.getCategoryList().get(i).getItemList();
}
}
Log.e("Chicken Size 1",String.valueOf(chickenList.size()));
}
@Override
public void onException(Exception e) {
final String error = e.getMessage();
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MeatActivity.this,error,Toast.LENGTH_LONG).show();
}
});
}
});
String muttonCategoryName = "Mutton";
catalogueService.getItemsByCategory(catalogueName, muttonCategoryName, new App42CallBack() {
@Override
public void onSuccess(Object o) {
Catalogue catalogue = (Catalogue) o;
for (int i = 0; i < catalogue.getCategoryList().size(); i++) {
String category = catalogue.getCategoryList().get(i).getName();
if (category.equals("Mutton")) {
muttonList = catalogue.getCategoryList().get(i).getItemList();
break;
}
}
}
@Override
public void onException(Exception e) {
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MeatActivity.this,"Unable to fetch data",Toast.LENGTH_SHORT).show();
}
});
}
});
String seaFoodName = "Sea Foods";
catalogueService.getItemsByCategory(catalogueName, seaFoodName, new App42CallBack() {
@Override
public void onSuccess(Object o) {
Catalogue catalogue = (Catalogue) o;
for (int i = 0; i < catalogue.getCategoryList().size(); i++) {
String category = catalogue.getCategoryList().get(i).getName();
if (category.equals("Sea Foods")) {
seaFoodList = catalogue.getCategoryList().get(i).getItemList();
break;
}
}
}
@Override
public void onException(Exception e) {
}
});
setupViewPager(viewPager);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new OneFragment(activityId, chickenList), "CHICKEN");
Log.e("Chicken Size 2",String.valueOf(chickenList.size()));
adapter.addFragment(new TwoFragment(activityId,muttonList), "MUTTON");
adapter.addFragment(new ThreeFragment(activityId,seaFoodList), "SEAFOODS");
viewPager.setAdapter(adapter);
}
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_-meat);
Toolbar Toolbar=(Toolbar)findViewById(R.id.Toolbar);
设置支持操作栏(工具栏);
catalogeservice catalogeservice=App42API.buildcatalogeservice();
Intent categoryIntent=getIntent();
catalogename=categoryIntent.getStringExtra(“目录”);
viewPager=(viewPager)findViewById(R.id.viewPager\u-meat);
tabLayout=(tabLayout)findViewById(R.id.tabs\u-meat);
FloatingActionButton fab=(FloatingActionButton)findViewById(R.id.fab);
fab.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图){
意向意向=新意向(MeatActivity.this、CartActivity.class);
星触觉(意向);
}
});
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
字符串chickenCategoryName=“Chicken”;
CatalogenService.getItemsByCategory(Catalogename,chickenCategoryName,new App42CallBack(){
@凌驾
成功时的公共无效(对象o){
目录=(目录)o;
对于(int i=0;i
实际上,问题是您正在进行异步网络调用。
做这样的事-
声明一个类级变量计数器
整数计数器
现在,在三个onSuccess()方法中的每一个方法中,只需执行以下操作
counter ++;
setupViewPager();
在setupViewPager方法中添加检查
setupViewPager(ViewPager viewPager) {
if(counter == 3){
// your code to set the adapter
}
}
实际上,问题是您正在进行异步网络调用。 做这样的事- 声明一个类级变量计数器 整数计数器 现在,在三个onSuccess()方法中的每一个方法中,只需执行以下操作
counter ++;
setupViewPager();
在setupViewPager方法中添加检查
setupViewPager(ViewPager viewPager) {
if(counter == 3){
// your code to set the adapter
}
}