利用selector设置ImageButton不同状态下的背景图片

1、自定义MyButton类

public class MyButton extends Button {

//This constructormust be

public MyButton(Context context, AttributeSet attrs) {   super(context, attrs); }

public MyButton(Context context) {   super(context); }

private Paint mPaint = null; private String mText; private int mX, mY;

public void onSetText(String text, int nLeft, int nBottom, int nTextSize,    int nTextColor) {   mPaint = new Paint();   mPaint.setTextSize(nTextSize);   mPaint.setColor(nTextColor);   this.mText = text;   this.mX = nLeft;   this.mY = nBottom; }

private int mDownBmpId, mUpBmpId;

public void onSetBmp(int nDownID, int nUpID) {   this.mDownBmpId = nDownID;   this.mUpBmpId = nUpID; }

@Override public void onDraw(Canvas canvas) {

  if (mPaint != null)    canvas.drawText(mText, mX, mY, mPaint);   super.onDraw(canvas); }

@Override public boolean onTouchEvent(MotionEvent event) {   if (event.getAction() == MotionEvent.ACTION_DOWN) {    super.setBackgroundResource(mDownBmpId);   } else if (event.getAction() == MotionEvent.ACTION_UP) {    super.setBackgroundResource(mUpBmpId);   }   return super.onTouchEvent(event); } }

2、 在xml布局文件中添加MyButton控件，像应用普通的Button控件一样。

  <com.MyButton    android:id="@+id/test_btn" android:layout_width="120px"    android:layout_height="fill_parent" android:text="Test"    android:background="@drawable/btn_u" />

其中com.MyButton是你定义的MyButton类所在的包名

3、在onCreate()中加载MyButton控件。

  MyButton btn = (MyButton)findViewById(R.id.test_btn);   btn.onSetBmp(R.drawable.btn_d, R.drawable.btn_u);

其中btn_d表示为按下btn时背景图片，btn_u为默认状态下btn背景图片