Android 在imageview中更改图像

我制作了一个android应用程序，可以在5秒后更改imageview中的图像。但是图像会叠加在创建imageview时选择的图像上。我不想要该图像。请帮助，这是代码

MainActivity.java

public class MainActivity extends Activity {
    Handler handler = new Handler();
    int count;
    int images[] = { R.drawable.c1, 
            R.drawable.c12,
            R.drawable.c3, 
            R.drawable.c4,
            R.drawable.c5, 
            R.drawable.c6,
            R.drawable.c7 };
    ImageView imageView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
         imageView = (ImageView) findViewById(R.id.imageView1); 

        handler.postDelayed(changeImage, 5000);
    }
    Runnable changeImage = new Runnable() {

        @Override
        public void run() {

            if (count >6) {
                handler.removeCallbacks(changeImage);
            } else {

                if (count >= 6)
                    count = 0;
                AlphaAnimation animation1 = new AlphaAnimation(0.5f, 1.0f); //here is a bit of animation for ya ;)
                animation1.setDuration(5000);
                animation1.setStartOffset(1300); //time for that color effect
                animation1.setFillAfter(true);
                imageView.startAnimation(animation1);
                imageView.setBackgroundResource(images[count++]);
                handler.postDelayed(changeImage, 5000);
                }
        }
    };

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.change.MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="206dp"
        android:layout_marginLeft="44dp"
        android:layout_toRightOf="@+id/textView1"
        android:src="@drawable/ic_launcher" />

</RelativeLayout>

而不是使用

imageView.setBackgroundResource(images[count++]);

试一试

---

我添加了imageView.setImageDrawable（null），它成功了

imageView.setImageResource(images[count++]);