Question

我有一个arraylist，每个索引也有一个arraylist。列表视图中列出了每个索引。如何在两个活动之间传递数据？我尝试了这些代码，但是当我点击列表视图时，它就崩溃了。

on my mainAcitivity

FuelView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        Intent intents = new Intent(MainActivity.this, EditEntry.class);
        String i = String.valueOf(position);
        intents.putExtra(KEY, i);
        startActivity(intents);`
     }
}

on my secondActivity

 loadFromFile();
    Intent intents = getIntent();
    final int index = Integer.valueOf(intents.getStringExtra(MainActivity.KEY));
    findEntry(index);

在findEntry函数

上

Entrylist Entrylist = Entrylists.get(index);

    EditText new_date = (EditText) findViewById(R.id.date);
    new_date.setText(Entrylist.getDate().toString());
    EditText new_station = (EditText) findViewById(R.id.station);
    new_station.setText(Entrylist.getStation().toString());
    EditText new_odometer= (EditText) findViewById(R.id.odometer);
    new_odometer.setText(Entrylist.getOdometer().toString());
    EditText new_grade = (EditText) findViewById(R.id.fuel_grade);
    new_grade.setText(Entrylist.getGrade().toString());
    EditText new_amount = (EditText) findViewById(R.id.fuel_amount);
    new_amount.setText(Entrylist.getAmount().toString());
    EditText new_cost = (EditText) findViewById(R.id.unit_cost);
    new_cost.setText(Entrylist.getCost().toString());

    Button save = (Button) findViewById(R.id.button2);
    save.setText("Save");

这是错误

 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.larin.aolin1_fueltrack/com.example.larin.aolin1_fueltrack.EditEntry}: java.lang.NumberFormatException: Invalid int: "null"
                                                                                    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
                                                                                    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
                                                                                    at android.app.ActivityThread.access$600(ActivityThread.java:141)
                                                                                    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
                                                                                    at android.os.Handler.dispatchMessage(Handler.java:99)
                                                                                    at android.os.Looper.loop(Looper.java:137)
                                                                                    at android.app.ActivityThread.main(ActivityThread.java:5103)
                                                                                    at java.lang.reflect.Method.invokeNative(Native Method)
                                                                                    at java.lang.reflect.Method.invoke(Method.java:525)
                                                                                    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
                                                                                    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
                                                                                    at dalvik.system.NativeStart.main(Native Method)
                                                                                 Caused by: java.lang.NumberFormatException: Invalid int: "null"
                                                                                    at java.lang.Integer.invalidInt(Integer.java:138)
                                                                                    at java.lang.Integer.parseInt(Integer.java:355)
                                                                                    at java.lang.Integer.parseInt(Integer.java:332)
                                                                                    at java.lang.Integer.valueOf(Integer.java:490)
                                                                                    at com.example.larin.aolin1_fueltrack.EditEntry.onCreate(EditEntry.java:41)
                                                                                    at android.app.Activity.performCreate(Activity.java:5133)
                                                                                    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
                                                                                    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
                                                                                    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261) 
                                                                                    at android.app.ActivityThread.access$600(ActivityThread.java:141) 
                                                                                    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256) 
                                                                                    at android.os.Handler.dispatchMessage(Handler.java:99) 
                                                                                    at android.os.Looper.loop(Looper.java:137) 
                                                                                    at android.app.ActivityThread.main(ActivityThread.java:5103) 
                                                                                    at java.lang.reflect.Method.invokeNative(Native Method) 
                                                                                    at java.lang.reflect.Method.invoke(Method.java:525) 
                                                                                    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737) 
                                                                                    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
                                                                                    at dalvik.system.NativeStart.main(Native Method)

Answer 1

您是否尝试使用？

解析索引

@Component({
  selector: 'my-app',
  directives: [NavbarComponent, ROUTER_DIRECTIVES],
  template: `
    <my-navbar></my-navbar>
    <router-outlet></router-outlet>
})
class AppComponent {
    constructor(dcl: DynamicComponentLoader, elementRef: ElementRef) {
        dcl.loadNextToLocation(SidebarComponent, elementRef);
    }
}

此外，您可以通过意图发送int值：

<my-app>
  <my-navbar></my-navbar>
  <router-outlet></router-outlet>
</my-app>
<my-sidebar>Sidebar</my-sidebar>

如何在两个活动之间传输数据

1 个答案: