相关疑难解决方法(0)

我试图以编程方式更改布局颜色但是相对布局(尝试线性布局但没有更改),但无法更改它.

尝试调试应用程序也无济于事,没有与我的TAG相关的消息.

布局最初打印后,应用程序停止运行.

package com.test.intentdemo;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
//import android.os.SystemClock;
import android.widget.RelativeLayout;
import android.util.*;
import java.lang.Thread;

public class intentDemo extends Activity {
    /** Called when the activity is first created. */
    RelativeLayout lLayout;
    public static final String TAG="MyActivity";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        lLayout = (RelativeLayout) findViewById(R.layout.main);
        if (Log.isLoggable(TAG,0))
        {
            Log.e(TAG,"ERROR BEFORE");
            Log.i(TAG,"INFO BEFORE");
            Log.d(TAG,"DEBUG BEFORE");

            lLayout.setBackgroundColor(Color.parseColor("#000000"));
            //SystemClock.sleep(2000);
            try
            {
                Thread.currentThread();
                Thread.sleep(2000);
            }
            catch (Exception e)
            {
                //e.message();
            }

            Log.e(TAG,"ERROR AFTER");
            Log.i(TAG,"INFO AFTER");
            Log.d(TAG,"DEBUG …