java - 定期更新 textview 背景

Question

我试图插入一个处理程序以每 x 秒更新一次 widget_textview 背景，但我不知道放置什么以及放置在哪里

        int i;
        if (i==1) {
            TextView myTxt = (TextView) findViewById(R.id.widget_textview);
            myTxt.setBackgroundResource(R.drawable.pic1);
            i++;
                  }else if(i==2) {
                    TextView myTxt = (TextView) findViewById(R.id.widget_textview);
                    myTxt.setBackgroundResource(R.drawable.pic2);
                    i++;
                  }else if(i==3) {
                    TextView myTxt = (TextView) findViewById(R.id.widget_textview);
                myTxt.setBackgroundResource(R.drawable.pic1);
                i=2;
                  }else {
                i++;
            }

我不能把它放在任何地方，在任何地方我放置这个代码我在 textview 中出现错误

这是我的代码

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.os.Handler;
import android.widget.RemoteViews;
import android.widget.TextView;

public class Widget extends AppWidgetProvider {
    private Handler handler = new Handler();
    RemoteViews views;
    AppWidgetManager appWidgetManager;
    ComponentName currentWidget;
    Context context;
    DateFormat format = new SimpleDateFormat("HH:mm");
    public void onUpdate(Context context, AppWidgetManager appWidgetManager,
            int[] appWidgetIds) {
        this.context = context;
        this.appWidgetManager = appWidgetManager;
        views = new RemoteViews(context.getPackageName(), R.layout.widget);
        currentWidget = new ComponentName(context, Widget.class);
        handler.removeCallbacks(UpdateWidget);
        handler.postDelayed(UpdateWidget, 100);

    }

    final Runnable UpdateWidget = new Runnable() {
        public void run() {

            Intent informationIntent = new Intent(context, MainActivity.class);
            PendingIntent infoPendingIntent = PendingIntent.getActivity(
                    context, 0, informationIntent, 0);
            views.setOnClickPendingIntent(R.id.Widget, infoPendingIntent);


            views.setTextViewText(R.id.widget_textview,
                    "" + format.format(new Date()));
            appWidgetManager.updateAppWidget(currentWidget, views);
            handler.postDelayed(UpdateWidget, 1000);



        }
    };

    @Override
    public void onDisabled(Context context) {
        super.onDisabled(context);
        handler.removeCallbacks(UpdateWidget);
    }
}

Answer 1

put this in your handler class implementations onHandleMessage() method.This method is overridden.

    public class MyHandler extends Hadnler(

           onHandlerMessage(Message msg){

        //your code you want to put

}
}