Question

我的应用程序中有一项服务和一项活动。 service通过用户的操作获取字符串，并将该字符串传递给活动。在这里，我成功获取活动的字符串值并显示在活动屏幕上。

我在活动中有一个列表视图，字符串值应该按顺序显示在该列表中。我的问题是我只能在列表视图中显示最近输入的一个项目。之前输入的字符串未显示。

因此，每次我必须从服务中获取字符串，该字符串应与listview一起显示在列表视图中。请帮帮我..谢谢。

我的活动是......

  public class MainActivity extends AppCompatActivity {


String pichi;
SharedPreferences pref=null;
ListView list;
private ArrayList<String> strArray;
int i;

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

    list=(ListView)findViewById(R.id.offlineList);

    pref= PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
    pichi=pref.getString("KEY","default");

    strArray=new ArrayList<String>();
    if (strArray.contains(pichi)){
        Toast.makeText(getApplicationContext(),"Link already exists",Toast.LENGTH_LONG).show();
    }else {
        int count = list.getCount();
        for ( i = 0; i < count; i++) {
            strArray.add("Row" + i);
        }
        final ArrayAdapter<String> adapter = new ArrayAdapter<String>
                (MainActivity.this, android.R.layout.simple_list_item_1, strArray);
        if (!list.equals(i)) {
            strArray.add(pichi);
            adapter.notifyDataSetChanged();
        }
        list.setAdapter(adapter);
    }

}

public void startService(View view) {
    startService(new Intent(MainActivity.this, CheckService.class));

}

}

其中startService（视图视图）是按下按钮的动作。

我的服务是......

   public class CheckService extends Service {


public CheckService() {
}

@Override
public IBinder onBind(Intent intent) {
    // TODO: Return the communication channel to the service.
    throw new UnsupportedOperationException("Not yet implemented");
}

String a;
Intent dialogIntent;

public void onCreate() {
    super.onCreate();

}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    Log.i("LocalService", "Received Start id" + startId + ":" + intent);

    final ClipboardManager clipboard = (ClipboardManager) this.getSystemService(Context.CLIPBOARD_SERVICE);
    clipboard.addPrimaryClipChangedListener(new ClipboardManager.OnPrimaryClipChangedListener() {
        public void onPrimaryClipChanged() {
            a = clipboard.getText().toString();
            if (Patterns.WEB_URL.matcher(a).matches()){

                dialogIntent = new Intent(CheckService.this, DialogActivity.class);
                dialogIntent.putExtra("text",a);
                dialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                startActivity(dialogIntent);
        }
            else if (!URLUtil.isValidUrl(a)){
             //   Toast.makeText(CheckService.this, "text is not a url link", Toast.LENGTH_LONG).show();
            }
        }
    });
    return super.onStartCommand(intent, flags, startId);

}


@Override
public void onStart(Intent intent, int startId) {
    // Perform your long running operations here.
 //   Toast.makeText(this, "Service Started", Toast.LENGTH_LONG).show();
}

@Override
public void onDestroy() {
    Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
    stopService(dialogIntent);
}

}

在服务中，我有一个警告对话框，我可以从中获取字符串值...

我的对话活动是.....

  public class DialogActivity extends Activity{

AlertDialog alert;
String receivedText;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Bundle bundle=getIntent().getExtras();
    receivedText=bundle.getString("text","default");

    final AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder
            .setTitle("yoLobee")
            .setMessage("save to yoLobee offline..?" )
            .setIcon(R.drawable.logo)
            .setCancelable(true)
            .setNeutralButton("SHARE", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, int i) {
                    Intent sendIntent = new Intent();
                    sendIntent.setAction(Intent.ACTION_SEND);
                    sendIntent.putExtra(Intent.EXTRA_TEXT, receivedText);
                    sendIntent.setType("text/plain");
                    startActivity(Intent.createChooser(sendIntent,receivedText));
                }
            })
            .setNegativeButton("NO", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, int i) {
                    alert.dismiss();
                    alert.dismiss();
                    builder.setCancelable(true);
                }
            })
            .setPositiveButton("YES", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    Toast.makeText(DialogActivity.this, "Link saved to yoLobee..", Toast.LENGTH_LONG).show();
                    SharedPreferences pref= PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
                    SharedPreferences.Editor edit = pref.edit();
                    edit.putString("KEY",receivedText);
                    edit.commit();
               //     edit.apply();

                }
            });

    alert = builder.create();
    alert.setCanceledOnTouchOutside(true);
    setFinishOnTouchOutside(true);
    alert.setCancelable(true);
    alert.show();
    WindowManager.LayoutParams lp = new WindowManager.LayoutParams();
    lp.copyFrom(alert.getWindow().getAttributes());
    lp.width = WindowManager.LayoutParams.MATCH_PARENT;
    lp.height = WindowManager.LayoutParams.WRAP_CONTENT;
    Window window = alert.getWindow();
    WindowManager.LayoutParams wlp = window.getAttributes();
    wlp.gravity = Gravity.TOP;
    wlp.flags &= ~WindowManager.LayoutParams.FLAG_DIM_BEHIND;
    window.setAttributes(wlp);
}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (event.getAction() == KeyEvent.ACTION_DOWN) {
        alert.cancel();
        alert.dismiss();
    }
    return super.onKeyDown(keyCode, event);
}

@Override
public void onBackPressed() {
    super.onBackPressed();
    alert.cancel();
    alert.dismiss();
}

}

所以从对话框活动我得到字符串值并显示在列表中。该列表仅显示来自服务的最新字符串值，因为它一次获得一个值。我希望列表显示从服务中检索的字符串列表。

Answer 1

如果您提供一段代码来查看它将会很有帮助。阅读你的问题似乎是你正在编写用于填充列表的数组。

只需从活动中获取字符串并将其添加到您用于显示listview的数组中，并调用notifyDataSetChanged（）。它会起作用

Answer 2

我认为int count = list.getCount();中的这一行onCreate会返回0，因为到目前为止您没有向list添加任何项目。

在listview中显示字符串数据，每个yime

2 个答案: