所以我遇到了一个问题，我在列表视图中单击了一个项目，它做了一些额外的操作，然后继续我的下一个活动。我遇到一个问题，我的应用程序进入黑屏，控制台告诉我
I/Choreographer：跳过了630帧！应用程序可能在其主线程上做了太多的工作。
我试过阅读Async，但我不知道如何在代码中使用它。所以我发布了我的主要活动，因为这是在没有与第二个活动交互的情况下发生的。
public class MainActivity extends AppCompatActivity {
ListView ListofList;
ArrayList<String> Lists;
ArrayAdapter<String> ListAdapter;
Button button;
ArrayList<String> Subject = new ArrayList<>();
int Size = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListofList = findViewById(R.id.LofL);
Lists = new ArrayList<String>();
ListAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, Lists);
ListofList.setAdapter(ListAdapter);
button = findViewById(R.id.AddList);
Lists.add("Test");
ListofList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent i = new Intent(getBaseContext(), ItemList.class);
String s = (String) ListofList.getItemAtPosition(position);
i.putExtra("Title", s);
i.putExtra("size", Size);
int a = 0;
for (String t : Subject) {
i.putExtra("Item" + a, t);
a++;
}
startActivityForResult(i, 2);
}
});
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(getBaseContext(), CreateItem.class);
String message = "Please enter the name of the list below.";
i.putExtra("mess", message);
startActivityForResult(i, 1);
}
});
}
@Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
Bundle extras = getIntent().getExtras();
if (data == null) {
}
if (data != null) {
if (requestCode == 1) {
String item = (data.getStringExtra("item"));
Lists.add(item);
ListAdapter.notifyDataSetChanged();
}
}
if (requestCode == 2) {
ArrayList<String> subject = new ArrayList<String>();
int i = 0;
assert data != null;
int size = (data.getIntExtra("ListSize", 0));
Size = size;
while (i <= size) {
String item = (data.getStringExtra("item" + i));
subject.add(item);
i++;
}
Subject = subject;
}
}
}应Ben p.的要求
public class ItemList extends AppCompatActivity {
static ArrayList<String> customItems;
ArrayAdapter<String> adapter;
ListView lvItems;
Button button;
Button button2;
ArrayAdapter<String> trashAdapter;
ArrayList<String> trash;
ListView itemtrash;
static TextView Title;
String Tit;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_item_list);
Title = findViewById(R.id.Title);
//set up Item List
customItems = new ArrayList<String>();
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, customItems);
lvItems = (ListView) findViewById(R.id.lvItems);
//Set up trash List
trash = new ArrayList<String>();
trashAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, trash);
itemtrash = findViewById(R.id.itemtrash);
//Initialize Buttons
button = findViewById(R.id.AddItem);
button2 = findViewById(R.id.ClearTrash);
Bundle extras = getIntent().getExtras();
if (extras != null) {
((TextView)findViewById(R.id.Title)).setText(extras.getString("Title"));
Tit = extras.getString("Title");
int i = 0;
int size = (extras.getInt("size", 0));
while (i <= size) {
String item = (extras.getString("Item" + i));
if (item == null) {
continue;
}
customItems.add(item);
i++;
}
}
//CharSequence Titlefilter = Title.getText();
//lvItems.setTextFilterEnabled(true);
//ItemList.this.adapter.getFilter().filter(Titlefilter);
//adapter.notifyDataSetChanged();
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(getBaseContext(), CreateItem.class);
String message = "Please enter new item below.";
i.putExtra("mess", message);
startActivityForResult(i, 1);
}
});
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
trashAdapter.clear();
trashAdapter.notifyDataSetChanged();
}
});
lvItems.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String s = adapter.getItem(position);
trashAdapter.add(s);
adapter.remove(s);
assert s != null;
adapter.notifyDataSetChanged();
trashAdapter.notifyDataSetChanged();
}
});
itemtrash.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String s = trashAdapter.getItem(position);
customItems.add(s);
trash.remove(s);
adapter.notifyDataSetChanged();
trashAdapter.notifyDataSetChanged();
}
});
lvItems.setAdapter(adapter);
itemtrash.setAdapter(trashAdapter);
}
@Override
public void onBackPressed() {
Intent i = new Intent();
int a = 0;
for (String s : customItems){
String t = adapter.getItem(a);
i.putExtra("item" + a, t);
a++;
}
int size = customItems.size();
i.putExtra("ListSize", size);
setResult(2, i);
finish();
}
@Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
Bundle extras = getIntent().getExtras();
if (data == null) {
}
if (data != null) {
String item = (data.getStringExtra("item"));
String title = Tit;
customItems.add(title + "nn" + item);
adapter.notifyDataSetChanged();
}
}
}我想明白了。在ItemList活动中，我意外地用进行了一个无限循环。